Method for adsorption isolation of monomethyl-substituted paraffins

FIELD: separation of organic compounds.

SUBSTANCE: invention concerns adsorption isolation processes and can be used when isolating monomethyl-substituted paraffins from hydrocarbon mixtures. Gist of invention resides in that a method for adsorption isolation with simulated moving bed designed for isolation of monomethyl-substituted paraffin C8-C14 is realized by passing initial mixture through adsorbent bed at air/fuel ratio between 0.5 and 1.5, 30-120°C, and operation cycle time 20-60 min. Thereafter, adsorbed monomethyl-substituted paraffin is selectively isolated from adsorbent bed when in contact with desorbent. Initial mixture containing monomethyl-substituted paraffins further contains at least another acyclic nonlinear hydrocarbon with the same number of carbon atoms and less than 5% of normal C8-C14-paraffins. Adsorbent includes silicate.

EFFECT: increased selectivity of isolation.

10 cl

 

The technical field to which the invention relates.

The present invention relates to a method of adsorptive separation of hydrocarbons. More specifically, the present invention relates to a method of continuous simulated countercurrent adsorptive excretion monomethylarsonic paraffins from mixtures containing other hydrocarbons with the same number of carbon atoms in the molecule. The preferred application of the method is the selection With10-C15monomethylarsonic paraffins of high-boiling oil fraction depleted in n-paraffins.

The forerunner of most modern detergents are petrochemical products. Currently, the main precursor of detergent is linear alkylbenzene (LAB), which is traditionally produced by alkylation of benzene with linear olefins with long chains of normal structure (line). The present invention is directed to obtaining monomethylarsonic acyclic olefins and paraffins, which may be released as standalone products or used for the production of various petrochemical products in the subsequent alkylation or oxidation. The following description mainly refers to the selection and use of monomethylarsonic hydrocarbons for p the receipt of petrochemical precursors detergents and basically, to obtain detergents based on alkyl benzenes.

Some qualitative characteristics alkylbenzenesulfonate (ABS) detergents are determined by the chemical structure of the side alkyl chain. So, for example, linear alkyl groups provide enhanced Biodegradability of the molecule. Other characteristics of the detergent, such as effectiveness in harsh and cold water and a tendency to foam, also depend on the structure of the side chain and its components. Recently it was found that highly desirable predecessors detergents can be obtained from olefins, the main carbon chain which contains, on average, one side of methyl chain. These products have been called "weak" branched paraffins. The alkyl benzenes containing such monoethylene side chain, can be used by themselves or in a mixture of linear alkyl benzenes to obtain a variety of detergents and cleaning products with superior performance-related properties in cold and hard water. This quality is a deviation from the existing preference given side chains of normal structure. This unexpected advantage monomethylarsonic alkyl benzenes as ingredients of detergents is described in US-A-6232282 B1 and US-A-6228829 B1. Special and what aspect of the present invention relates to the production of monomethylamine hydrocarbons, designed for use in subsequent receipt of the detergents described in these two patents.

The level of technology

Widespread use of detergents and other cleaning agents has led to the widespread development of research in the field of production of detergents and development of their recipes. Although the detergents can be formed from a large number of different compounds, most of the world's supply is formed from chemical substances on the basis of alkyl benzenes. These substances are produced in petrochemical complexes with aromatic hydrocarbons, typically benzene, is subjected to the alkylation of an olefin, a side chain which has a desirable structure and contains the desired number of carbon atoms. In fact, the olefin is usually a mixture of different olefins, form a homologous series with the number of carbon atoms of from three to five. Consider the olefins can be obtained from alternative sources. For example, they can be obtained by oligomerization of olefins With3or4or by the polymerization of ethylene. For economic reasons, preferred by obtaining olefins is their production by dehydrogenation of the corresponding paraffin.

Paraffin molecules containing 8-15 carbon atoms, in a significant number of the Oh present in relatively cheap, high-boiling kerosene fraction of crude oil or refined fractions of crude oil. The number of carbon atoms is determined by the boiling range of kerosene. The selection of paraffins from kerosene by adsorption becomes the leading commercial source precursors of olefins. Olefins production begins with the selection of paraffins with the same number of carbon atoms in the adsorption allocation of kerosene. After that paraffins are passed through a catalytic dehydrogenation zone in which some of the paraffins are converted to olefins. Thereafter, the resulting mixture of paraffins and olefins is fed to the alkylation zone in which the olefins react with the aromatic substrate. General process flow diagram of this process is shown in the patent US-A-5276231 related to the improvement of the adsorption highlight side of aromatic hydrocarbons from a stream, coming from the dehydrogenation zone. In WO 99/-07656 indicates that the process paraffins can be separated into the product of two consecutive zones adsorption separation, in one of which are normal paraffins, and the other monomethylamine paraffins.

Description use the adsorptive separation simulated moving bed for separation of high-boiling paraffins is ethanol kerosene fraction of this presentation, made R.C. Shuiz et al. the 2nd International Conference on detergents in Montreux, Switzerland, October 5-10, 1986. The scheme provides several optional stages, as fractionation and Hydrotreating.

Successful implementation specific adsorption separation is determined by many factors. The main of them is the composition used in the process of the adsorbent (stationary phase) and desorbent (the mobile phase). Other factors, mainly related to technological conditions, which are very important for successful commercialization. In the method of the present invention is used as an adsorbent containing molecular sieve known in this area as silicalite. Application silicalite in the adsorption separation of paraffins described in the patent US-A-4965521, which relates to the production of high-octane components of gasoline. Consistent application of silicalite and zeolite 5A to highlight monomethylarsonic alkanes described in the article submitted to Journal of Chromatography, 316 (1984) 333-341. Successful use silicalite for separating normal paraffins, cyclic hydrocarbons and hydrocarbons with branched chain described in US-A-4367364 and US-A-4455444. Consider separating different from the process of the present invention, since it corresponds to the process described in city vannoy earlier reference to the International Conference on detergents and refers to the separation of normal paraffins.

Special pore structure silicalite predetermined attempt its use for the separation of linear (normal) paraffins. However silicalite also has catalytic properties that may cause undesired conversion of olefins in the course of such separation. The use of adsorbents on the basis of silicalite for the separation of linear olefins and linear hydrocarbons, as well as ways of handling silicalite aimed to restore its catalytic activity, described in US-A-5262144; US-A-5276246 and US-A-5292990.

It was found that temperature is an important technological parameter SMB processes. Temperature intervals traditional SMB processes with respect to the normal paraffins contained in UA-A-4367364 and US-A-4992618. In the latter patent also mentions that the cycle time is 60 minutes.

Disclosure of inventions

The present invention relates to a method of adsorptive separation simulated moving bed, intending to highlight monomethylarsonic paraffins or olefins from mixtures with other paraffins or olefins nonlinear structure, for example with circular or silkroadonline paraffin with the same number of carbon atoms. The present invention is characterized by a specific process conditions, including the length of the business cycle and those which the temperature in the adsorption zone.

A broad aspect of the embodiment of the present invention may be characterized as a process of separation simulated moving bed, designed to highlight monomethylarsonic paraffins C8-C14from the original mixtures containing monomethylamine paraffin and at least one other acyclic hydrocarbons With8-C14non-linear structure with the same number of carbon atoms, in which the initial mixture contains less than 5 wt.% normal paraffins C8-C14moreover , this method consists of passing the mixture through a bed of adsorbent under conditions which assure the removal of her less than 95 wt.% monomethylamine paraffin, providing a ratio A/F of 0.5-1.5, the temperature of 30-120°and the work cycle duration of 20-60 minutes, followed by separation selectively adsorbed monomethylamine wax layer of the adsorbent with the result of the contact layer desorbent. Although the degree of extraction of monomethylaniline intentionally limited to, its value is preferably more than 50% and more preferably above 75%. The preferred range of values allocating monomethylamine paraffin is 80-95%. The preferred length of the business cycle is 20-45 minutes.

The implementation of the invention

In numerous methods described in the patent literature, MOLEKULYaRNAYa adsorbents are used to separate the different hydrocarbons and other chemical compounds, for example aromatic hydrocarbons, paraffins, chlorinated aromatic hydrocarbons and chiral compounds. Separation in the center of attention of such methods involves the process of separating molecules by their shape. Such processes include separation of linear and non-linear aliphatic hydrocarbons, as well as linear and non-linear olefinic hydrocarbons. Adsorptive separation is often used in the case when (1) shared compounds have similar volatility, which prevents their separation by fractional distillation, or (2) when it is desirable to carry out the separation of a number of compounds according to the classes. An example of the separation of hydrocarbons according to the classes can serve as the selection of normal paraffin or aromatic hydrocarbons from the mixture containing aromatic hydrocarbons and a mixture of paraffins. Another example of the separation of classes is the separation of linear paraffins C10-C14and other hydrocarbons, C10-C14described in the above-cited references.

The need for detergents based monomethylarsonic alkyl benzenes disclosed in WO 99/07656 and above cited U.S. patents. These links also provides a General description is the selection of the desired monomethylarsonic paraffins from the raffinate, out of the zone adsorptive separation using second zone adsorption separation. In the cited reference describes several adsorbents include zeolites and silicoaluminate with special pore size, and proposed use of low molecular weight n-paraffin, for example heptane or octane as desorbent.

The aim of the present invention is an improved method of adsorptive separation monomethylarsonic hydrocarbons and other hydrocarbons. A special object of the invention is to develop a process for the adsorptive separation simulated moving bed with the intent of highlighting the normal and monomethylarsonic paraffins from a stream of mixed hydrocarbons.

The method of the present invention relates to the separation and allocation of monomethylarsonic paraffins from a mixture containing other non-linear paraffins. This way, in many ways similar to the methods used for separation of normal paraffins from similar materials. The flow of raw material can also contain normal paraffins or olefins with the same number of carbon atoms, although it is preferable that the concentration of normal paraffins was relatively low, for example less than 2 or 5 wt.%. In other words, the raw material can be used, the flow of raffinate PR is against progress adsorption separation, in which carry out efficient allocation of mostly normal paraffins.

Effluent from this zone adsorption separation usually contains almost no sulfur compounds in the Hydrotreating, or other possible treatments of the raw material supplied in the following area adsorptive separation. However, it has been found that the preferred adsorbent of the present invention are able to effectively perform their functions in the presence of significant quantities of organic sulfur compounds. This unexpected result makes use of this method of processing the raw or not subjected to Hydrotreating raw materials. Used in the text the term "dehydroacetate" means that raw materials are not brought into contact with a Hydrotreating catalyst in the presence of hydrogen to reduce the sulfur content. So, for example, raw materials can contain up to 10,000 ppm or more organic sulfur, although it's usual content is less than 1000 h/million Kerosene fraction of the raw material may contain 0.1 to 30 wt.% n-paraffins and 5-25 wt.% DFID. Hydrotreating not affect the content of paraffins in the flow of raw materials.

The possibility of alternative raw materials in the adsorption zone has a number of advantages. There is no need for the hydrotreatment of the feedstock. Consequently, there is no need to use the installation for hikooki the weave or, if necessary, Refine the later stages of the technological process can be used in the hydrotreatment of a smaller size. Because this process is not required to carry out the hydrotreatment of the feedstock, the characteristics of the raw material does not change as it happens in the saturation of aromatic components. As a result of this happen smaller changes in the composition of kerosene in the course of back mixing of the raffinate with the remainder of the crude oil. Consider the impact of the removal of paraffins to change the physical properties of the main flow of kerosene, for example its viscosity or lubricity, which is very important to use this material for transportation fuels. Extraction monomethylarsonic paraffins and normal paraffins may be useful for raw kerosene, as a means of improving the cold flowability. In other words, decreased concentration moderately branched paraffins provides "dewaxing" flow of kerosene. Thus, the present invention is a sequence of stages, including the division of the original thread kerosene feedstock into two fractions, extraction of monomethylaniline from the first oil fraction by the method of adsorption allocation to education stream monomethylarsonic paraffins,Hydrotreating flow monomethylaniline and its subsequent use for the manufacture of detergents, and re-mixing the two kerosene fractions with receiving a flow of a modified kerosene feedstock. When using silicalite adsorbent stream monomethylamine paraffin product may also contain normal paraffins. Because the preferred raw materials for the adsorption separation according to the invention in the beginning was treated in the adsorption zone the purpose of separation of normal paraffins, raw materials for separation according to the invention generally should be subjected to Hydrotreating because of serotonergically adsorbents used in the area of adsorption of normal paraffins.

Multi-stage method may be characterized as a simulated process with a moving bed adsorptive excretion monomethylaniline from a mixture containing monomethylamine paraffin, and normal paraffin and acyclic hydrocarbon nonlinear structure with the same number of carbon atoms, and such an approach is to separate dehydroacetic process stream with a boiling range of kerosene with the formation of the source mixture comprising hydrocarbons containing 8-14 carbon atoms, and containing more than 50 ppm organic sulfur, and the first process stream, passing the mixture through a bed of adsorbent containing silicalite in conditions that provide the General destruction of less than 95% paraffin wax from monomethylarsonic the initial mixture at a temperature of 35-80° With, the allocation of the flow of raffinate containing needsomeone hydrocarbons, and the allocation of the flow of the extract containing the allocated selectively adsorbed normal and monomethylarsonic the wax layer of the adsorbent as a result of his contact with desorbent; and mixing the flow of raffinate with the rest of dehydroacetic process stream with a boiling range of kerosene with the education process stream, which derive from the process.

Selected monomethylamine hydrocarbons can be used as such. They can be used to obtain a large number of other chemicals, such as oxygen-containing compounds such as alcohols and ethers, and carbohydrates such as sugar. Selected paraffins can be subjected to such conversion stages, as chlorination, nitration or alkylation for the production of such products as solvents and lubricants. However, the preferred final destination monomethylarsonic paraffins is getting the ingredients or precursors detergents, such as alkyl benzenes. The resulting alkyl benzenes can be transformed into a modified Las (MAS) as a result of sulfonation using sulfur trioxide or sulfuric acid with subsequent neutral what izala. Hydrocarbon products can also be used for the production of other precursors or ingredients of detergents, including ethoxylates and sulfates of alcohols, or even sulfonated carboxylic acids, using standard sequence of known reactions. Branched olefinic hydrocarbons of the present invention can also be converted into the ingredients of cleaning products in the alkylation of toluene or phenol with subsequent alkoxycarbonyl or sulfonation, or by the reaction of hydroformylation, followed by the second stage, for example alkoxysilane, sulfation, phosphating, oxidation or a combination of these stages. After that, these ingredients often combine with other components, for example, brighteners, enzymes, neopatnij components, activators, secondary surfactants, etc. Derivatives of alkyl benzene used in the production of a variety of anionic surfactants, compoundname in detergents, cleaning products, soap bars, and means for washing or dishwashing. Monomethylarsonic hydrocarbon or monomethylamine alkylbenzene may be subjected to oxidation to obtain C8-C18alcohols or acids, or sulfurous. Received the s thus the alcohols may constitute the finished products or petrochemical raw materials, used to obtain detergenty products.

The processes of adsorption separation can be carried out in batch or continuous modes, including two or more layers of adsorbent employed in the cycle. However, significant technological and economic benefits to encourage separation in continuous mode, which produces a product with a homogeneous composition. The preferred method of implementing continuous process and a homogeneous product is the use of technology for modeling moving layer. In this regard, the following description of the invention only relates to the separation of different monomethylarsonic paraffins and other hydrocarbons, which can be implemented in large-scale installations with a simulated moving bed (SMB).

Performance SMB installations based on criteria such as the purity and yield of the product depends to a large number of process parameters such as operating temperature and composition of desorbent. The inventors have found that as a result of deliberate limitations highlight the desired wax product can be unexpectedly and significantly reduced the size and cost of the adsorption zone. Although one might expect that the reduction in regeneration of paraffin should bring to mind is neseniyu required amount of adsorbent, unexpectedly, it was found that when this happens this interaction with other process parameters, in particular the duration of the cycle and operating temperature, which provides a disproportionately large increase in overall performance when using the same amount of adsorbent. In other words, at low speed retrieve the decrease in the amount of adsorbent required for obtaining the prescribed number of product, significantly above the value that would be expected based on the reduction of the cycle time. It should be noted that in this comparison the total number of wax, extracted during the process, remains constant. Consequently, such a process requires a large amount of load. The volume flow rate of raw material increase to compensate for the decrease in retrieval. For example, the percentage of extraction can be lowered from 98 to 92, resulting in the flow of raffinate remains greater number of the desired paraffin. To compensate for increase flow speed.

This unexpected result may be used to reduce the required size of the new area for adsorption. On the other hand, it can be used to increase the performance of an existing installation.

Most SMB installations, adsorbs the frame separation simulate countercurrent movement of the adsorbent and the flow of raw materials. This modeling is carried out using proven commercial technology, in which the adsorbent have motionless in the number of sublayers in one or more cylindrical chambers. The position in which the threads involved in the process, proceed in camera and leave them periodically travel to the sublayer sublayer along the length of the cameras with the adsorbent, resulting in the implementation of the technological cycle streams enter or leave from various sublayers. Usually in the way there are at least four streams (raw desorbent, extract and raffinate) and the position of the entrance to the chamber flows of raw materials and desorbent and exit from the chamber flows extract and raffinate periodically move in the same direction at specified intervals. Every periodically increasing shift in the position of the moving points allocates or removes fluid from the various sublayers of the adsorbent inside the chamber. The time required to position the insertion point has passed completely through all sublayers, represents the duration of the operating cycle of the process. Such movement may be performed using a predetermined line for each input flow in each sublayer. However, this can significantly increase the cost of the process, and therefore such miniapolis repeatedly. Usually used only one line for each sublayer, and each line gives one of the four process streams at a certain point of the cycle. Typically, such a modeling method also involves the use of a pump with variable feed speed with which the fluid from one end of the vessel with the adsorbent is moved to the other end by a single continuous path.

Processes with simulation of the moving layer typically includes at least three or four different stages, which are performed sequentially in separate areas of one or both of the vertical cylindrical adsorption chambers. The position of the zones in the adsorption chamber(s) changes gradually. Each of these zones typically is formed of a plurality of sublayers of the adsorbent, and the number of sublayers in the area can vary from 2-3 to 8-10. The most widely used devices for carrying out the business processes usually contain layer 24. Sublayers are structurally separated from each other by means of horizontal nets for collection/distribution of the liquid. Each grid is attached to the transmission line, the defining point of transfer, in which the process flow, such as flow of raffinate and extract, proceed in the vertical adsorption chamber or out of them.

In this technical field generally accepted to describe the process of also blondage separation simulated moving bed (SMB) with reference to the zone. Usually this process is carried out using 4 or 5 zones. The first contact between the flow of raw material and the adsorbent is carried out in zone 1, zone adsorption. The adsorbent or stationary phase in zone 1 contains the desired class of compounds and is surrounded by a fluid that contains unwanted connections, i.e. the raffinate. This liquid is removed from the adsorbent in zone II, called the purification zone. In the area of cleaning unwanted components of the raffinate washed out of the volume of voids adsorption layer by using a material that is easily separated from the desired component by fractional distillation. In the desorption zone or zone III adsorption chamber, the desired compound is separated from the adsorbent as a result of exposure to the adsorbent or washing desorbent (the mobile phase). Selected the desired connection and the accompanying desorbent removed from the adsorbent and do in the area of extraction. Zone IV is a certain amount of adsorbent, is placed between zones I and III, which is used to separate these zones. In zone IV desorbent partially withdrawn from the adsorbent in the form of a mixture of desorbent and unwanted components of the original thread. The fluid flow through zone IV prevents contamination zone III fluid zone I with flow parallel to the simulated movement of the adsorbent from the zone III area I. A more detailed explanation of the processes by modeling the moving layer, see Adsorption, Liquid Separation encyclopedia Kirk-Othmer Encyclopedia of Chemical Technology and in the above-cited references. The terms "against the flow (upstream)and downstream (downstream)" are used in their usual meaning and are interpreted with reference to the General direction of the flow in the adsorption chamber. Thus, if the fluid flows through the vertical adsorption camera mostly down, the term "against the flow" is equivalent to the upper position of the camera. Common methods of carrying out the process of adsorption separation simulated moving bed is fairly well described in the open literature. For example, a General description of the process intended for separation of para-xylene using SMB, refer to p.70 Chemical Engineering Progress (vol.55 No. 9)issued September 10, 1970, a Generalized description of the process with emphasis on mathematical modeling was presented 6-11 May 1983 D.B. Broughton, S.A. Gembicki at the International Conference on Fundamentals of Adsorption", Schloss Elmau, Upper Bavaria, Germany. Another useful link that you cited in the present description, is US-A-2985589, which describes the practical application of the processes of adsorption separation simulated moving bed. In other numerous and available sources describe many mechanically the aspects of the system with the simulated moving bed, including rotary valves for the distribution of the different liquid flow lines in the layer of adsorbent, the internal arrangement of the adsorption chambers and control systems.

A cyclic advancement of the input and output streams in this simulation can be performed using a variety of systems or using butterfly valves, as described in US-A-3040777 in USA-3422848. The concepts described can be used in equipment of various sizes, from pilot plant described in US-A-3706812 to commercial petrochemical plants, changing the volumetric flow rate from a few cm3per hour to thousands of gallons per hour. In large-scale installations are typically used rotary valves with port for each transmission line, whereas in small-scale high-pressure installations are typically used only two or three ports. The present invention can also be carried out in the mode of the process with concurrent threads, as described in US-A-4402832 and US-A-4478721. Functions and properties of adsorbents and desorbent for chromatographic separation of liquid components are well known, and in this respect we can refer to the patent US-A-4642397, which is included in the present description, additional description of the basic principles of adsorption.

At the stage of adsorption question about the ECCA the initial mixture, contains various compounds that result in contact with the adsorbent at adsorption conditions and one or more compounds or class of compounds are selectively adsorbed and retained by the adsorbent while the other compounds the mixture to remain almost neadsorbirovanne condition. Usually adsorb the desired connection. The initial mixture may contain a variety of compounds, including isomers of the desired compound. For example, the original stream of a mixture of xylenes, may contain ethylbenzene and/or aromatic hydrocarbons With9and may be subjected to treatment aimed at highlighting special isomer using a suitable pair of adsorbent/desorbent working in proper conditions.

In the case where the adsorbent contains close to equilibrium quantity is more selectively adsorbed compounds, referred to as the "rich" adsorbent. In the next stage of the process needsomeone (raffinate) components of the mixture to remove the empty spaces between the particles of adsorbent and the surface of the adsorbent. This depleted liquid and any desorbent, which is mixed with it during passage through the adsorption zone at this stage, derived from the process as part of the process stream, which is called the flow of raffinate. Then adsorbed with the unity isolated from the enriched adsorbent at desorption conditions and at the stage of desorption, through his contact with the stream containing desorbent. Desorbent displaces the desired compound from the adsorbent with the formation of the extraction flow, which is usually served in a fractionation zone to isolate the desired compounds from the extraction stream containing a mixture of the desired compounds and desorbent. It should be noted that in some circumstances, the desired product is in the flow of raffinate, and not in the flow of the extract and in the process adsorb undesirable substances.

Below is the definition of the various terms used in the present description. The term "original mix" refers to a mixture containing one or more components of the extract and one or more components of the raffinate to be split using this method. The term "source flow" means the flow of the mixture to set in contact with the adsorbent used in this process. The term "component of the extract" refers to a compound or class of compounds, which are more selectively adsorbed by the adsorbent, while the term "raffinate component" refers to a compound or class of compounds which adsorb less selectively. The term "desorbent" refers to a material capable of and used for desorption of the component of the extract from the adsorbent.

Ter is in the flow of raffinate" refers to the flow, in which component of the raffinate is removed from the layer of adsorbent after the adsorption of the components of the extract. Over time the composition of the flow of raffinate, after advancing transmission lines subsurface fluid varies from almost 100% desorbent to almost 100% of the raffinate. The term "extract stream" or "output stream extract" refers to the thread in which the material of the extract desorbed by desorbent, removed from the bed of adsorbent. The composition of the extract stream may vary and contain from 100% desorbent to 100% of the components of the extract.

The extract stream and the flow of raffinate come in the separation device, usually in the column fractional distillation, which is regenerated at least part of desorbent and formed the extracted product and refined product. The extract stream may be enriched component of the extract, or may hold him in higher quantity. When using the term "enriched" with reference to the process flow, it is assumed that the concentration of the indicated compound or class of compounds is more than 50 mole percent.

Desorbent used in the method of the present invention may include a single component or a mixture of two or more components. A suitable mixture for separation monomethylarsonic paraffins performance is made by a mixture of normal and isoparaffin, or other branched paraffins, for example, a mixture of n-pentane and isooctane in a ratio of 70/30 (5 mol%). As desorbitada mixture it is preferable to use a mixture containing 40-60% branched paraffins. Desorbent can also be a single component, such as n-heptane or n-hexane. The preferred normal paraffin is n-hexane and desorbent may contain 0-100% of normal paraffin. The normal paraffins buildings are an effective desorbent, the most powerful of which is n-hexane. Other preferred desorbent is a mixture of normal paraffin C5-C8with methylcyclopropene containing the same number of carbon atoms, for example a 50/50 mixture of n-hexane to cyclohexane. Such mixtures may contain 10-90 vol.% cycloparaffins. The preferred cycloparaffins are cyclopentane, cyclohexane and methylcyclohexane. In all cases examined, desorbent are hydrocarbons with lower boiling point, which facilitates their separation from the components of the extract and the raffinate by means of fractional distillation. In this regard, the molecule is preferred desorbent contains 5-8 carbon atoms.

For various separation processes have been developed a special pair of adsorbent/desorbent and the use of special Combi the purpose adsorbent/desorbent is usually the decisive factor for the successful implementation of the commercial process. The preferred adsorbent designed for use in regeneration of monomethylaniline includes silicalite. Silicalite fairly well described in the literature. He disclosed and claimed in US-A-4061724, issued in the name Grose et al. A more detailed description of this matter, see "Silicalite, A New considered are hydrophobic Crystalline Silica Molecular Sieve", Nature, vol.271, Feb. 9, 1978, which is incorporated into the present application in connection with presents in it a description, and the present characteristics silicalite. Usually silicalite characterized by the ratio of silica:alumina 300:1. Silicalite is a molecular sieve based on the hydrophobic crystalline silica having a MFI structure type of intersecting arcuate-orthogonal channels with two spheres geometry, including 6A rings and 1-5,7 And ellipses on the primary axis. This geometry provides high selectivity silicalite, as size-selective molecular sieve. Because of the fact that the structure of the material does not contain aluminum and consists of silicon dioxide, silicalite does not possess ion-exchange properties. Silicalite is not a zeolite.

The active component of the adsorbent is usually used in the form of small agglomerates having high physical strength and resistance to abrasion. Such agglomerates contain the act is wny absorbent material, dispersed in an amorphous, inorganic matrix, called a bonding material containing the channels and cavities that provides access to the absorbent material. Methods for the formation of such agglomerates of crystalline powders include adding an inorganic binder, usually clay, containing silicon dioxide and aluminum oxide, a powder of the adsorbent of high purity with the formation of the wet mixture. The binder contributes to the formation and agglomeration of crystalline particles. The stirred mixture of clay and adsorbent can be subjected to extrusion with the formation of cylindrical granules or shape of her balls, which are then calcined to transform the clay into an amorphous binder, with considerable mechanical strength. The adsorbent may also be associated inside of irregular shaped particles obtained by spray drying or crushing more massive formations, followed by classification by size. Thus, the particles of the adsorbent may be in the form of extrudates, tablets, macroter or granules of the desired particle size, preferably from 1.2 mm to 250 microns (16-60 mesh (Standard U.S. Mesh). As a binder material typically use clay kaolin type, water-permeable organic polymers or silica.

Specialists in this field the ti technique should be clear, on the technical characteristics of a particular adsorbent can have a significant impact various factors not related to its composition, for example, the process conditions, the composition of the primary stream and the water content of the adsorbent. Therefore, the optimal composition of the adsorbent and operating conditions of the process are dependent on a number of interrelated factors. One such factor is the water content of the adsorbent, which is expressed in terms of known test "loss of combustion" (LOI). According to the LOI test content of volatile substances in a zeolite adsorbent is determined by the difference in mass of the sample of the adsorbent before and after drying at 500°in conditions of blowing inert gas such as nitrogen for a time sufficient to achieve constant weight. In the method of the present invention it is preferable that the water content of the adsorbent in accordance with the test LOI at 900°was less than 7.0%, preferably 0-4,0 wt%.

Usually silicalite present in the particles of the adsorbent in quantities 75-98 wt.% based on the composition of volatile components. Compositions that do not contain volatile substances, usually obtained after calcination of the adsorbent at 900°to remove all volatile components. The remaining adsorbent is an organic matrix binder mixed with chalk and active particles adsorbing material. This matrix material may serve as an additive in the manufacturing process of the active adsorption material, which is associated with a possible partial purification silicalite during its production.

In the practical implementation of the present invention the initial mixture containing one or more monomethylarsonic branched hydrocarbons and at least one hydrocarbon nonlinear structure with the same number of carbon atoms, but other patterns, is passed through one or more layers of adsorbent, which selectively adsorbs monomethylarsonic branched hydrocarbon, but allows other components of the source stream to pass through the adsorption zone in the same condition. Raw materials can only contain paraffin hydrocarbons or may be a mixture of paraffin and aromatic hydrocarbons. For example, the initial mixture for the method of the present invention can contain significant amounts of aromatic hydrocarbons and may also contain some amounts of paraffins with many branches, paraffins with a large number of carbon atoms in branching, cycloparaffins, branched cycloparaffins or other compounds with a boiling point close to the boiling point of the desired isomer. At a certain point in time, given remaining capacity the hell is Orbeta, the flow of raw material through the adsorbent stop, and the adsorbent is subjected to washing to remove readsorbing materials surrounding the adsorbent. After that, the desired isomer is desorbed from the adsorbent, passing through the adsorption layer flow desorbent. Neabsorbiruemye component desorbent (isooctane) is preferably also used for leaching readsorbing materials of the volume of voids around and inside the adsorbent.

An important characteristic of the adsorbent is the exchange rate desorbent a component of the extract of the original mixture or, in other words, the relative rate of desorption of the extracted component. This characteristic is directly related to the number of desorbent which should be used in the process for selecting a component of the extract from the adsorbent. Higher speed such sharing reduces the number of desorbent required to remove the extracted component and, therefore, contribute to the reduction of production costs. At higher speeds such exchange, through the process can be pumped fewer desorbent with its subsequent separation from the extract stream with the purpose of reuse. The exchange rate is often temperature dependent. In the ideal case, desorbent must have selectivity with respect to all component is to extract, equal to 1 or more less than 1 and, therefore, all components of the extract can decorrelates within a single class at an acceptable velocity desorbent, and the components of the extract can displace desorbent in the next stage of adsorption.

In the processes of adsorption separation, which is preferably carried out in continuous mode at almost constant temperature and pressure, ensuring the preservation of the liquid phase, desorbent should be chosen in such a way that it matches multiple criteria. First, desorbent must displace a component of the extract from the adsorbent when a sufficient mass flow rate and thus should not occur too its strong adsorption, which can prevent the displacement of desorbent component of the extract in the next cycle of adsorption. In terms of selectivity, it is preferable that the adsorbent had a higher selectivity with respect to all components of the extract, compared with the component of the raffinate than desorbent in relation to the components of the raffinate. Secondly, desorbent must be compatible with the particular adsorbent and the original mix. More specifically, the material must not reduce or compromise the capacity of the adsorbent or selectivity component of the extract relative to the component of the raffinate. In addition to this is, should not enter into a chemical reaction or cause a chemical reaction of a component of an extract or a raffinate component. The threads of the extract and raffinate are usually deleted from the volume of the voids of the adsorbent in the mixture with desorbent and any reaction involving desorbent, as well as a component of an extract or a raffinate component, or both such component will complicate or impede the selection of the product. Desorbent should also be easily separated from the components of the extract and raffinate, for example, by fractionation. Finally, desorbent should be readily available materials having reasonable cost.

The original mixture, which can be used in the method of the present invention, typically are derived kerosene, and get them at previous stages of separation. Such methods of preparation, as fractional distillation, by their nature imprecise and as a result of their implementation produces a stream containing a mixture of compounds. It is expected that the selection of the desired paraffins from kerosene, but not oligomerization or other types of synthesis, will provide the lowest cost of the corresponding faction and the predominant source of raw materials. The number of carbon atoms in monomethylarsonic waxes suitable for the production of LAB, can range 8-16, preferably the number of carbon atoms is equal to four. In the way altoadige invention interval 10-14 is often preferred, the most preferred range is from 11 to 13, which is associated with improved detergent properties. The number of carbon atoms corresponds to linear paraffins boiling in the boiling range of kerosene, and consequently, the kerosene fraction obtained at a refinery, fractionation of crude oil or through conversion processes, can serve as suitable precursors to the original thread of the present invention. In that case, if the adsorbent is sensitive to sulfur, the fraction obtained by the fractionation of crude oil, will require Hydrotreating to remove sulfur and/or nitrogen before it enters the process of the present invention. The temperature interval of boiling oil fraction regulate pre-fractionation with getting paraffins with the desired number of carbon atoms. In special cases, the boiling range may be limited in such a way that will dominate paraffins with a specific number of carbon atoms. Kerosene fractions contain a very large number of different hydrocarbons, and therefore the raw material for the method of the present invention may contain 200 or more different compounds.

The concentration of normal and monomethylarsonic paraffins in the feedstock will affect the composition of the recycled extract product. Preference is sustained fashion alkylbenzene contains a side chain of normal structure and monomethylamine side chains. Therefore, it is desirable that the extract contained 20-25% of normal paraffin. The original thread, producing alkyl benzenes of this nature may be available in the form of a stream of the raffinate from the process of adsorption separation, which selectively allocated paraffins normal structure. The flow of raffinate from this installation does not contain such impurities as sulfur or nitrogen-containing compounds, and has a low concentration of normal paraffins.

The use of such a flow of raffinate as raw materials for separation processes of the present invention provides integration of this method with the existing equipment for the production of LAB, and two-stage adsorptive separation carried out sequentially, as shown in the previously cited publication WO 99/07656. Then separate normal paraffins and monomethylamine paraffins may be subjected to various treatments. For example, each paraffin stream may be independently subjected to dehydrogenation and used for the alkylation of aromatic compounds with specific alkylbenzene products, which optionally can be mixed with each other. On the other hand, paraffin products highlighted in two separate operations, can be mixed with each other and olefins, polucen the e them each paraffin, can be mixed at the stage of alkylation. In this regard, the raw material is supplied in the subsequent dehydrogenation zone or alkylation may contain product separation using the method of the invention plus 10-35% vol. normal hydrocarbons allocated to another separation stage, or provided from other sources.

In the practical implementation of the present invention does not require significant changes in operating conditions, the composition of the adsorbent or desorbent inside adsorption chamber or during the various process steps. In other words, during the whole process, it is preferable that the adsorbent was kept at a constant temperature and pressure. Preferably, in the whole adsorption chamber was maintained practically uniform pressure and to the pressure change was associated only with hydrostatic pressure and the technological route. Preferably, all process streams flowed into the layer of adsorbent at the same temperature.

General conditions of adsorption include a temperature in the range of 25-120°C, With a preferred value in the range of 35-85°C. a Particularly preferred temperature range is 30-65°C. the advantages of relatively low operating temperatures associated with deviations from the expectation. About is a rule you can expect the lowering of the temperature will lead to increased purity of the product, but to decrease its output. Conditions for adsorption also preferably include a pressure sufficient to maintain all process environments in the liquid phase; used pressure can be set in the range from atmospheric to 600 lb/in2. The desorption conditions usually include the same temperature and pressure that are used for adsorption. Small changes can be preferred depending on the composition of the adsorbent and raw materials.

The method of the present invention operates at a feed speed, which is characterized by a volume ratio of the simulated flow rate of the selective pore volume of the adsorbent (A) to a flow rate capable of adsorption of the components of the raw material (F). Ratio A/F is set in the range of 0.5-1.5.

A very important parameter SMB installation is the "cycle time". Cycle time represents the time for which the input position of the supply line makes one complete pass through all the sublayers and returns to its original position. A shorter cycle time is equivalent to the increase in the speed of the simulated movement of the adsorbent. The regulation of the duration of the cycle allows you to adjust the amount of adsorbent in contact with the raw material during his stay in the BPA is briannah cameras. The preferred cycle time is 20-45 minutes.

Other important technological option which has not been studied to date, is the percentage of separating the desired paraffin. Usually, it was assumed that for a given quantity of adsorbent is desirable to maximize the allocation of the desired paraffin in order to maximize performance. However, the inventors have found that by lowering the level of separation to a value less than 95% vol. and preferably less than 90 vol.% you can improve the overall performance of the process. In this case we have to process more raw materials, but could be improved the performance of an existing installation or can be used in a new installation of smaller size than in the case when the emission rates set in accordance with the industrial standard for value, 95 or 98%. Because this process uses raw materials are petroleum-based, such raw materials are usually available in sufficient quantity and increase the feed rate of raw materials is not a significant problem.

An unexpected advantage of the method of the present invention may become apparent when determining performance SBM small scale pilot plant used to obtain flow monomethylamine parafinovogo product. Source of raw materials for the pilot installation was a kerosene fraction of crude oil, which was subjected to Hydrotreating and then distillation, leaving it mostly contained hydrocarbons, C10-C15. In the pre-adsorption separation the purpose of separation of normal paraffins received raw materials, depleted normal paraffins. Such raw material is contained 2.5 wt.% normal paraffins and 16.2 wt.% monomethylarsonic paraffins. The received raw Podwale zone SMB adsorption pilot plant at more of the following temperatures. The adsorbent contained silicalite associated with a bonding material on the basis of inert silicon oxide.

In the first series of experiments in the area of adsorption maintained a temperature of 120°C. This temperature is typical for similar processes of isolation of normal paraffins. Adsorbent served silicalite associated with silicon oxide. The duration of the operating cycle of the pilot installation was 45 minutes. The flow rate was regulated in such a way as to obtain a ratio A/F equal to 1.20. Desorbent was a mixture of 58% of n-pentane and 42% of isooctane. Then the temperature in the adsorption zone was lowered and the experiment was repeated. At each temperature was determined by the purity of the selected extract material (normal paraffins plus monomethyl nesennye paraffins). The results are shown in Table 1. From the presented data shows that the purity is increased by carrying out the process at low temperatures.

no experienceTemperature. °Purity (extract), %
112085,4
2100of 87.8
380to 91.6
46593,2

Based on the results of the tests, a second series of experiments were conducted at a constant temperature of 65°C. Varied the length of the business cycle. Used the same raw materials, adsorbent, etc. But the process was regulated so that in each experiment, the purity was 92%, as in experiment 3 above. The results of the tests are presented in Table 2. The results show that decreasing the duration of the cycle purity highlighted in the extract product containing normal and MMP paraffins, not decreased.

no experienceCycle timeRegeneration, %
54568
6 68
73670
82070

As follows from the presented data, reducing the duration of the working cycle SMB pilot plant unexpectedly did not lead to a decline in the rate of excretion of the mixed extract products. Postulated that the observed effect is associated with less time to establish equilibrium between the raw material and the adsorbent. Following the conventional logic regarding the use of a smaller amount of adsorbent, it was possible to predict the decline in total output with this drastic reduction in the duration of the working cycle.

Because in the process of adsorption separation usually is rather expensive raw materials, the development of new processes trying to find new approaches to increase the degree of extraction. In this regard, some large-scale commercial SMB installation work when the degrees of extraction 98 or even 99 wt.%. In the next series of experiments the targets were the degree of recovery and the purity of the product. The flow rate of the raw materials was adjusted so as to maintain the ratio A/F is equal to 0.92. The results are presented below in Table 3. The results show that the overall purity of the product (normal paraffins plus monomethylethanolamine) suddenly increases with the decrease of the cycle time and increasing productivity.

From the obtained results it also follows that by reducing the percentage of extraction can be processed sufficiently large number of raw materials, thereby increasing the number of the selected material. The result of this approach may improve the performance of existing SMB installation or new installation of a smaller size.

Table 3
no experienceCycle timeThe purity of MMP + NPPerformance MMP+NP
93792,5100 (base value)
1035of 92.7105
113293,0113

1. The way adsorptive separation simulated moving bed, designed to highlight the C8-C14monomethylamine paraffin from the original mixture, which consists in passing the mixture through a bed of adsorbent at operating conditions, including the ratio A/F in the range of 0.5 to 1.5, the temperature of 30-120°and the duration of the working cycle 20-60 min, and subsequent allocation selectively adsorbed monomethylaniline wax layer of the adsorbent in the contact layer of the adsorbent with desorbent is m, in which the initial mixture contains monomethylarsonic paraffin and at least one other acyclic hydrocarbon nonlinear structure with the same number of carbon atoms, and C8-C14monomethylarsonic paraffin, and the initial mixture contains less than 5 wt.% normal paraffins With8-C14and the adsorbent includes silicalite.

2. The method according to claim 1, wherein the adsorbent includes silicalite, and the original mixture is fed into the adsorbent at operating conditions for extraction of the mixture to less than 90% monomethylamine paraffins.

3. The method according to any of claim 1 or 2, wherein the conditions include 30-65°C.

4. The method according to any of claim 1 or 2, wherein the conditions include a temperature in the range of 35-80°C.

5. The method according to claim 1, wherein a duration of the duty cycle is 20-45 minutes

6. The method according to claim 1, in which the conditions used provide the cure of the mixture to less than 95% monomethylamine paraffins.

7. The method according to any one of claims 1, 2 or 6, in which the initial mixture constitutes at least part of the flow of raffinate from the process of adsorption separation intended for separation of normal paraffins.

8. The way adsorptive separation simulated moving bed, designed to highlight monosubstituted wax mixture containing monomethyltin is on the normal paraffin and paraffin, as well as acyclic hydrocarbon nonlinear structure with the same number of carbon atoms, and the method includes the fractionation is not subjected to Hydrotreating process stream with a boiling range of kerosene with the aim of obtaining the original mixture, which includes hydrocarbons containing 8-14 carbon atoms and contains more than 50 cmln organic sulfur, and the first process stream by passing the mixture through a bed of adsorbent comprising silicalite when the conditions for extraction of the mixture to less than 95% monomethylamine paraffin, and including a temperature in the range of 35-80°With, the allocation of the flow of raffinate containing needsomeone hydrocarbons and the allocation of the flow of the extract containing the selected selectively adsorbed normal and monomethylarsonic the wax layer of the adsorbent in the contact layer of the adsorbent with desorbent and mixing of the stream of the raffinate with the remaining part is not subjected to Hydrotreating process stream with a boiling range of kerosene, resulting in a process stream, which is withdrawn from the process.

9. The method according to claim 8, in which desorbent contains C5or6normal paraffin and/or methylcyclohexane.

10. The method according to claim 9, in which the mixture also contains extensive pair the ins.



 

Same patents:

The invention relates to agglomerated zeolite adsorbents based on faujasite with the ratio Si/Al in the range 1SiAl1,15 subjected to at least 70% of ion exchange on barium and possibly potassium, with mostly able to zeolitization binder

The invention relates to a method of separation of para-xylene from a feedstock containing a mixture of aromatic C8isomers

The invention relates to a method of separation using membrane molecular sieve in the separation of hydrocarbons and/or oxygenated products

The invention relates to gas processing and petrochemical industry and can be used for the separation of normal hydrocarbons, isotrate

The invention relates to the cracking of hydrocarbons, namely the recovery of olefins, in particular alkene from the exhaust gas by catalytic cracking

The invention relates to an adsorption separation of hydrocarbon mixtures, in particular adsorption methods of purification of liquid paraffins from aromatic hydrocarbons, and can be applied in the refining and petrochemical industry

The invention relates to new chemical compound dibenzalacetone the diphenylolpropane formula

SO2- OO-SO< / BR>
which can be used as a stationary liquid phase for gas chromatography analysis

FIELD: separation of organic compounds.

SUBSTANCE: invention concerns adsorption isolation processes and can be used when isolating monomethyl-substituted paraffins from hydrocarbon mixtures. Gist of invention resides in that a method for adsorption isolation with simulated moving bed designed for isolation of monomethyl-substituted paraffin C8-C14 is realized by passing initial mixture through adsorbent bed at air/fuel ratio between 0.5 and 1.5, 30-120°C, and operation cycle time 20-60 min. Thereafter, adsorbed monomethyl-substituted paraffin is selectively isolated from adsorbent bed when in contact with desorbent. Initial mixture containing monomethyl-substituted paraffins further contains at least another acyclic nonlinear hydrocarbon with the same number of carbon atoms and less than 5% of normal C8-C14-paraffins. Adsorbent includes silicate.

EFFECT: increased selectivity of isolation.

10 cl

FIELD: chemical industry; the methods of production of the phenylalkenes.

SUBSTANCE: the invention is pertaining to the production process of the catalytic alkylation of the benzol or its derivatives (the toluene and the ethylbenzene) by the higher monoolefins with production of the phenylalkanes. The method provides for the following stages: a) feeding the stream of the feed stock containing the first acyclic paraffin C8-C28 having 2 or 3 primary atoms of carbon with the first concentration and at least the second acyclic paraffin into the adsorption area for realization of the selective adsorption by the silicalite; introduction in the contact with the stream of the desorbent, extractions of the adsorption extract from the area of adsorption with the second concentration of the first acyclic paraffin, which exceeds the first concentration; b) feeding a part of the extract of the adsorption into the area of dehydrogenation and extraction from the area of dehydrogenation of the stream of the products containing acyclic monoolefin having 2 or 3 primary atoms of carbon; c) feeding the feed stock containing the phenyl compound and a part of the stream of the products of dehydrogenation, containing the acyclic monoolefin into the area of alkylation at presence of the catalytic agent of the alkylation with production of phenylalkane containing oneС828 aliphatic alkyl group; d) extraction of the phenylalkane from the area of the alkylation. The composition of the modified alkylbenzene includes alkylbenzene, where the link of the modified alkylbenzene is produced by the above described method, and it is intended for usage as the lubrication substance, or as the dope to the washing substance. The technical result of the invention is the upgraded technological process of alkylation of the phenyl compound with the help of the easily ramified monoolefins.

EFFECT: the invention ensures the upgraded technological process of alkylation of the phenyl compound with the help of the easily ramified monoolefins.

9 cl, 3 ex, 8 tbl, 2 dwg

FIELD: CHEMISTRY.

SUBSTANCE: agglomerated zeolite adsorbing materials are suggested. They contain inert bonding agent based on zeolite X with Si/Al ratio within 1.15 < Si/Al ≤ 1.5 range, with at least 90% of cation exchange centres are occupied by either barium ions only or barium and potassium ions. In the latter case, fraction of exchange centres occupied by potassium may be up to 1/3 of those occupied by barium and potassium. Remaining centres are occupied by alkali or earth metals other than barium. The Dubinin volume of these adsorbing materials measured using nitrogen adsorption at 77°К after vacuum degassing for 16 h at 300°С is 0.240 cm3/g or more.

EFFECT: resulting adsorbing materials are efficient for isolation of p-xylene from mixtures of isomers of aromatic hydrocarbons in liquid or gas phase.

13 cl, 4 ex

FIELD: chemistry.

SUBSTANCE: claimed is group of inventions related to method of purification of flows of initial substances, containing aromatic compounds, in processes of polymerisation or alkylation by contact of flows of initial substances with zeolites, characterised by the fact that flow of initial substances is passed through, at least, two zeolites 1 and 2, average size of zeolite 1 pores being from 0.3 to 0.5 nm, and of zeolite 2 - from 0.6 to 0.8 nm, as well as to method of obtaining alkylated aromatic compounds by interaction of aromatic compounds with olefins on catalyst, which is characterised by the fact that flow of initial substances, containing aromatic compounds, is subjected to preliminary processing by described above method. Claimed method of purification of flows of initial substances, containing aromatic compounds, allows to prolong catalyst service life in processes of polymerisation and alkylation.

EFFECT: prolonging catalyst service life in processes of polymerisation and alkylation.

9 cl, 2 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: one of method versions includes stages: (a) contacting at practically not reducing general pressure of gaseous mixture, containing xylol isomers, ethylbenzol and unadsorbable gas, with adsorbent, selective to paraxylol, which contains zeolite with pores of average size, in order to obtain paraxylol-depleted raffinate and effluent after desorption, containing product, enriched with paraxylol; unadsorbable gas contains hydrogen and does not react with xylol isomers and ethylbenzol; and (b) isomerisation of at least part of paraxylol-depleted raffinate. Stage of contacting is carried out in such way as to avoid necessity to subject raffinate to compressing before isomerisation, profitably eliminating expensive stages of compression.

EFFECT: improving method of obtaining paraxylol from xylol isomer mixture.

21 cl, 4 ex, 7 tbl, 7 dwg

FIELD: chemistry.

SUBSTANCE: present invention pertains to adsorption. Description is given of an adsorption method of removing methanol impurities from paraffin hydrocarbons in each phase at low temperature and atmospheric pressure using synthetic zeolite NaA, modified with active metals Ni or Ce, and recycling the adsorbent in a hydrogen stream.

EFFECT: invention shortens duration of the process, reduces power consumption and increases service life of the adsorbent.

8 ex

FIELD: chemistry.

SUBSTANCE: invention relates to versions of a method for alkylation of an alkylation substrate, which is an aromatic compound, using an alkylation agent, one of which involves: directing a crude stream of alkylation substrate, which contains the alkylation substrate in form of an aromatic compound, to an impurity adsorption zone which contains a cleaning adsorbent which contains clay or resin, which is selective towards impurities which contain basic organic nitrogen compounds, to obtain a cleaned stream of the alkyaltion substrate which contains the alkylation substrate in form of an aromatic compound, and nitriles; directing at least a portion of the cleaned stream of alkylation substrate and at least a portion of the reaction output stream to a separation zone; extraction of a contaminated stream of substrate from the separation zone, which contains the alkyaltion substrate in form of an aromatic compound, and nitriles; directing at least a portion of the contaminated stream of alkylation substrate which contains the alkylation substrate in form of an aromatic compound, at least 20 pts. wt per million of water and nitriles into a nitrogen adsorption zone, which functions at temperature 120-300°C and contains an adsorbent which contains acidic molecular sieves which are selective towards nitriles, and extraction of a denitrated substrate stream from the nitrogen adsorption zone, containing the alkylation substrate which is in form of an aromatic compound and has concentration of nitriles which is less than concentration of nitriles in the contaminated sustrate stream;and directing the alkylating agent and at least a portion of the denitrated substrate stream, which contains the alkylation substrate which is in form of an aromatic compound, into the alkylation reaction zone separate from the nitrogen adsorption zone, alkylation of the alkylation substrate, which is in form of an aromatic compound, with an alkylation agent over an alkylation catalyst to form an alkylation product and extraction of a reaction output stream containing an alkylation product from the alkylation reaction zone.

EFFECT: present invention enables creation of a protective layer which will adsorb nitriles from a stream of hydrocarbon material in the presence of water.

19 cl, 4 ex, 3 tbl, 9 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to agglomerated zeolite adsorbents. Disclosed is a powdered zeolite X based adsorbent with low content of silicon dioxide and containing barium or barium and calcium in an exchange complex. Disclosed also is a method of obtaining an agglomerated zeolite adsorbent, in which a mixture of zeolite clay and a silicon dioxide source is formed, treated with sodium hydroxide, washed and subjected to ion exchange. The adsorbent is recommended for use when separating sugar, alcohols containing several substituted hydrogen atoms, isomers of substituted toluene, cresols or when extracting paraxylene of very high purity.

EFFECT: invention enables to obtain an agglomerated adsorbent with small crystals and high mechanical strength.

22 cl, 7 tbl, 9 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to aggregated zeolite adsorbents based on X and LSX zeolites. The adsorbent contains zeolite X powder, substituted with at least 90% barium ions only or barium and potassium ions, where in exchangeable sites occupied by potassium, representing up to 1/3 of exchangeable sites occupied by barium and potassium ions, there are additional alkali or alkali-earth ions other than barium and potassium, as well as zeolite LSX powder substituted with at least 90% barium ions only or barium and potassium ions, where in exchangeable sites occupied by potassium, possibly representing up to 1/3 exchangeable sites occupied by barium and potassium ions, there are possibly additional alkali or alkali-earth ions other than barium and potassium, and also binder in an amount equal to or less than 20% of the total weight of the agglomerated zeolite adsorbent. The obtained adsorbents are efficient in separating C8 aromatic isomers, particularly xylenes, separating sugars, separating polyatomic alcohols, separating isomers of substituted toluenes, separating cresols and separating dichlorobenzenes.

EFFECT: higher efficiency.

16 cl, 1 dwg, 5 tbl, 10 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of separating at least one straight C4-C20 hydrocarbon from a fluid mixture containing said straight hydrocarbon and at least one branched isomer thereof. The method involves a step of bringing the fluid mixture into contact with an adsorbent which contains a porous organometallic skeletal material containing at least one at least bidentate organic compound, having a coordination bond with at least one metal ion for adsorption of the straight hydrocarbon, where the at least one at least bidentate organic compound is a monocyclic, bicyclic or polycyclic ring system and is unsubstituted or has one or more substitutes, independently selected from a group consisting of a halogen atom, C1-6-alkyl, phenyl, NH2, NH(C1-6-alkyl), N(C1-6-alkyl)2, OH, O-phenyl and OC1-6-alkyl, where the substitutes C1-6-alkyl and phenyl are unsubstituted or have one or more substitutes, independently selected from a group consisting of a halogen atom, NH2, NH(C1-6-alkyl), N(C1-6-alkyl)2, OH, O-phenyl and OC1-6-alkyl, wherein the ring system of the at least one at least bidentate organic compound is a substituted imidazole, and where said at least one metal ion is an ion of a metal selected from a group consisting of Zn, Cu, Co, Ni, Fe and Mn. The invention also relates to use of said porous organometallic skeletal material in the method of separating straight hydrocarbons from branched isomers thereof.

EFFECT: present invention provides an alternative, easily to make absorbent.

9 cl, 4 ex, 3 dwg

FIELD: separation of organic compounds.

SUBSTANCE: invention concerns adsorption isolation processes and can be used when isolating monomethyl-substituted paraffins from hydrocarbon mixtures. Gist of invention resides in that a method for adsorption isolation with simulated moving bed designed for isolation of monomethyl-substituted paraffin C8-C14 is realized by passing initial mixture through adsorbent bed at air/fuel ratio between 0.5 and 1.5, 30-120°C, and operation cycle time 20-60 min. Thereafter, adsorbed monomethyl-substituted paraffin is selectively isolated from adsorbent bed when in contact with desorbent. Initial mixture containing monomethyl-substituted paraffins further contains at least another acyclic nonlinear hydrocarbon with the same number of carbon atoms and less than 5% of normal C8-C14-paraffins. Adsorbent includes silicate.

EFFECT: increased selectivity of isolation.

10 cl

FIELD: technological processes.

SUBSTANCE: invention is related to the field of processing of high molecular carbon-bearing raw materials into lighter compounds and may be used in chemical and petrochemical industry for production of engine fuels, and also finished products and semi-finished products of organic synthesis. Method for processing of high molecular carbon-bearing raw materials into lighter compounds is executed in the presence of solid porous materials, process is executed in two stages, the first of which represents impregnation of porous material with carbon-bearing raw material, and the second one includes thermal treatment of impregnated porous material in anaerobic conditions. Thermal treatment of impregnated porous material is carried out by means of its intense heating with high-frequency electromagnetic radiation either by means of its intense heating due to short-term contact with heated surface, or by means of its intense heating by passage of electric current through it. Solid porous material is represented by widely porous oxide matrices or porous metals, or metal-containing composites, or carbon matrices.

EFFECT: simplification of stage of thermal processing of viscous material with production of lighter hydrocarbons purified from admixtures.

12 cl, 11 ex

Up!