The method of extraction of aromatic hydrocarbons from mixtures with non-aromatic hydrocarbons
(57) Abstract:Describes a better way of extracting aromatic hydrocarbons. As extractants of aromatic hydrocarbons from mixtures with non-aromatic hydrocarbons, in particular from catalization reforming proposed to use a mixture of diethylene glycol with N-formylmorpholine or triethylene glycol with sulfolane containing 5-6 wt.% water. This will reduce the ratio of extractant: raw materials 35-30% compared to di - and triethylene glycol, the temperature of the process straccia from 150 to 100 - 120oWith consumption of risaykl with 80-90 30-60 wt.%. The components are mixed extractants - deg and N-formylmorpholine, TAG and sulfolan have practically the same boiling point, which allows to maintain a constant composition of the extractants in the process of regeneration. The technical effect is to increase the efficiency of the allocation process of aromatic hydrocarbons. table 2. The invention relates to the refining industry and can be used for the recovery of benzene, toluene and xylenes from catalization reforming of gasoline fractions of oil 62-105oC and 62-140oC.Known method of extraction of the aromatics from the containing a series of 7 - Mas.% water (Sulimova A. D. "the Production of aromatic hydrocarbons from petroleum sources", M.: Chemistry, 1975, S. 304). The disadvantages of the method of extraction arenes mixtures of glycols with water is insufficient selectivity and low solvent capacity of the extractants according to the ratio of glycols is the low quality aromatic hydrocarbons by high concentration of impurities of saturated hydrocarbons, in particular, Methylcyclopentane in benzene.The consequences of low dissolving ability of mixtures of glycols with water are the high ratio of extractant to raw materials (8-15:1 wt.), high temperature extraction process (150oC), high consumption of acute water vapor in the distillation arenes from the extract phase.Closest to the technical essence and the achieved effect of the present invention method for separating aromatic hydrocarbons from mixtures thereof with non-aromatic using as extractant mixtures of di - and triethylene glycol with tetrahydrofurfuryl alcohol (TGFS) in a ratio of 70/30 (wt.) (SU 833938, C 07 C 7/10, 30.05.81).The disadvantage of this method is not only insufficient selectivity of mixtures of glycols with tetrahydrofurfuryl alcohol, n the basics by distillation, due to significant differences in the boiling points tetrahydrofurfurylamine of alcohol and diethylene glycol (T = 67oC) and triethylene glycol (T = 110oC). At boiling point TGPS the ratio of the pressure of saturated steam TGFS and the TAG is 31.4 and TGFS and deg - 5.9.With the purpose of increase of efficiency of process of separating aromatic hydrocarbons from mixtures thereof with saturated hydrocarbon liquid extraction as a selective solvent is proposed to use a mixture of diethylene glycol with N-formylmorpholine and triethylene glycol with sulfolane when the content of the glycol in a mixture of 70 wt.%, and second component 30 wt.%.A mixture of diethylene glycol with N-formylmorpholine outperforms extraction properties as diethylene glycol and a mixture of diethylene glycol with tetrahydrofurfuryl alcohol (PL. 1).Unlike in opposition to the invention, the components of the proposed mixed extractants have similar boiling point: TAG (287.4oC) and sulfolane (287.8oC), DEG (245oC) and N-formylmorpholine (244oC). The ratio of the pressure of saturated steam system components TAG - sulfolan - 1.008, and N-formylmorpholine - deg 1.004, i.e. these compounds ablauts leads to the increase of the coefficient of distribution and the degree of extraction of toluene, however, this reduces the concentration of toluene in the extract and the separation factor of hydrocarbons, because of lower selectivity TGFS compared with glycols.The addition of 30 wt.% sulfolane to TAG leads to an increase of all indicators of the extraction process as compared with the TAG (in the greatest degree increases the degree of extraction and the distribution coefficient of toluene), and with a mixture of TAG - TGFS (especially on the content of the toluene extract and partition coefficient). The results obtained with the proposed mixed extractant TAG - sulfolan due to the fact that he beats the TAG, and a mixture of TAG - TGFS both selectivity and solvent's ability to aromatic hydrocarbons.The pressure of 30 wt.% - formylmorpholine to DAG increases the degree of extraction and distribution coefficient of toluene compared to deg and increase all extraction parameters in comparison with a mixture of deg - TGFS proposed in opposition to the invention.The smaller the viscosity of the mixture DAG - N-formylmorpholine compared to the MONEY (for example, at 60oWith a dynamic viscosity of MONEY with 5 wt.% water 8.0 centipoise, and the viscosity of the mixture MONEY with 30 wt.% N-formylmorpholine, the temperature. Moreover, the extractant is superior to the watered at 150 degoC on all parameters of the extraction process.In table. 2 presents the results of a single-stage extraction of organs offered mixed extractants, as well as DAG and TAG from catalyzate reforming install LH-35-8/300B JSC "Kirishinefteorgsintez". When the extraction arenes TAG and a mixture of TAG - sulfolan used stable can produce the following composition, wt. %: benzene - 15.55, toluene - 17.25, arena C8- 1.90, saturated hydrocarbons - 65.3. When the extraction arenes deg and a mixture of deg - N-formylmorpholine used sample catalyzate with a higher content of arenes, wt.%: benzene - 19.6, toluene - 18.2, arena C8- 1.4, saturated hydrocarbons - 60.8.High dissolving ability of the proposed mixed extractants and lower viscosity compared to deg and TEG allows to reduce the temperature of the extraction process mixtures TAG - sulfolan and DAG - N-formylmorpholine from 150 to 70oC. thus, as shown in table. 2 results offer mixed extractants exceed watered DAG and TAG on all parameters of the extraction process - the distribution coefficients and the degree of extraction of arenes to as solving ability, and selectivity adding sulfolane to TAG and N-formylmorpholine to deg.In table. 3 presents the main parameters and results of a six-speed countercurrent extraction arenes from catalyzate reforming using TEG, deg, and the proposed mixed extractants. Adding to the TAG 30 wt.% sulfolane reduces the ratio of extractant to raw materials at 25 wt.% and temperature of the extraction process, and significantly reduce the consumption of risaykl. In this case, loss of arenes with rafinate phase decreases and the degree of their extraction, in particular toluene and arenes C8is raised.Adding to deg 30 wt.% N-formylmorpholine the ratio of the extractant to the raw material, the temperature of the extraction and consumption of risaykl can also be significantly reduced while increasing the degree of extraction of arenes.An important advantage of the process of extraction of the proposed mixed extractants is also in the reduction of specific energy consumption, due to the low process temperature, the ratio of extractant: raw materials, heats of vaporization, viscosity and specific heat capacities of mixtures TAG - sulfolan and DAG - N-formylmorpholine compared to TEG and deg. So, share the Olin - water at 100oC Cp= 2.51 j/goC. the Specific heat of the TAG with 8 wt. % water at 150oC Cp= 2.85 j/goC, and offer a mixture of TAG - sulfolan - water at 120oC Cp= 2.35 j/goC.Example 1.In a sealed vessel with a magnetic stirrer load of 50 g of material containing 35 wt.% toluene and 65 wt.% heptane and 100 g of solvent of the following composition: TAG - sulfolan (70/30 wt.). The mixture thermostatic for 30 min at 50oC under vigorous stirring. After sedimentation of the upper and lower layers separated. The top layer (rafinate phase) was washed with water, dried over calcium chloride, filtered off and weighed. Get 42.62 g of raffinate containing 26.8% toluene and 73,2% heptane. From the lower layer (extract phase) by distillation with water vapor is separated 7.25 g of extract containing 82.4% toluene and 17.6% heptane.Removing the toluene is 34.1% of the potential content in the initial mixture.Example 2.In a sealed vessel with a magnetic stirrer load of 50 g of material containing 35% of toluene and 65% heptane and 100 g/extractant of the following composition: DAG - N-formylmorpholine (70/30 wt.%). The mixture thermostatic for 30 min at 50oC when intensive phase allocate 7.45 g of extract, containing 78.6% of toluene. Removing toluene amounted to 33.5% of the content in raw materials.Example 3.In an airtight container with a stirrer load of 50 g catalyzate reforming containing 34.8% of aromatic hydrocarbons, and 100 g of solvent of the following composition, wt.%: triethylene glycol - 65,8, sulfolan - 28.2, water - 6.0.After stirring at a temperature of 70oC for 30 min and sedimentation of the upper and lower layers separated. By distillation with water vapor from the extract phase allocate 7.2 g of extract containing 77.6% aromatic hydrocarbons. The extraction of aromatic hydrocarbons totaled 32.0% of the content in the catalyzate reforming.Example 4.In an airtight container with a stirrer load of 50 g catalyzate reforming containing 39.2% of aromatic hydrocarbons, and 100 g of solvent of the following composition, wt.%: diethylene glycol - 66,5, N-formylmorpholine - 28.5, water is 5.0.After stirring and settling at a temperature of 70oC the upper and lower layers separated. By distillation with water vapor from the extract phase allocate 10.55 g of extract containing 74,7% aromatic hydrocarbons. Removing arenes 40.2% of the content in raw materials.Example 5.
1. Sulimov, A. D. Production of aromatic hydrocarbons from petroleum sources. - M.: Chemistry, 1975 - 304 S.2. Hrušov E. I., Shcherbina E. I. A. S. 833938, C 07 C 7/10, 1981. BI N 20, 1981. The method of extraction of aromatic hydrocarbons from mixtures with non-aromatic by liquid extraction with a selective solvent-based di - and triethylene glycol, characterized in that as the selective solvent used inseparable boiling mixture of diethylene glycol with N-formylmorpholine or triethylene glycol with sulfolane containing 5 to 6 wt.% water.
FIELD: petrochemical processes.
SUBSTANCE: simultaneous dehydrogenation of mixture containing alkyl and alkylaromatic hydrocarbons is followed by separating thus obtained dehydrogenated alkyl hydrocarbon and recycling it to alkylation unit. Dehydrogenation reactor-regenerator employs C2-C5-alkyl hydrocarbon as catalyst-transportation carrying medium.
EFFECT: increased process flexibility and extended choice of catalysts.
FIELD: organic synthesis catalysts.
SUBSTANCE: invention relates to catalyst for aromatization of alkanes, to a method of preparation thereof, and to aromatization of alkanes having from two to six carbon atoms in the molecule. Hydrocarbon aromatization method consists in that (a) C2-C6-alkane is brought into contact with at least one catalyst containing platinum supported by aluminum/silicon/germanium zeolite; and (b) aromatization product is isolated. Synthesis of above catalyst comprises following steps: (a) providing aluminum/silicon/germanium zeolite; (b) depositing platinum onto zeolite; (c) calcining zeolite. Hydrocarbon aromatization catalyst contains microporous aluminum/silicon/germanium zeolite and platinum deposited thereon. Invention further describes a method for preliminary treatment of hydrocarbon aromatization catalyst comprising following steps: (a) providing aluminum/silicon/germanium zeolite whereon platinum is deposited; (b) treating zeolite with hydrogen; (c) treating zeolite with sulfur compound; and (d) retreating zeolite with hydrogen.
EFFECT: increased and stabilized catalyst activity.
26 cl, 1 dwg, 5 tbl, 4 cl
SUBSTANCE: zeolite catalyst for process of conversion of straight-run gasoline to high-octane number component is described. The said catalyst contains high-silica zeolite with SiO2/Al2O3=60 and residual content of Na2О of 0.02 wt.% maximum, metal-modified, Pt, Ni, Zn or Fe metals being in nanopowder form. Content of the said metals in the catalyst is 1.5 wt.% maximum. Method to manufacture zeolite catalyst for conversion of straight-run gasoline to high-octane number component is described. The said method implies metal modification of zeolite, Pt, Ni, Zn or Fe metals being added to zeolite as nanopowders, produced by electric explosion of metal wire in argon, by dry pebble mixing in air at room temperature. Method to convert straight-run gasoline using the said catalyst is also described.
EFFECT: increase in catalyst activity and gasoline octane number, accompanied by increase in yield.
4 cl, 3 tbl, 4 ex
SUBSTANCE: method involves hydrocarbon transformation in a reactor in the presence of modified catalyst containing, mass %: 53.0-60.0 of ZSM-5 high-silica zeolite with the ratio of SiO2/Al2O3=39, 34.0-38.0 of Al2O3, 2.0-5.0 of B2O3, 1.0-5.0 of Zn, 0.0-5.0 of W, 0.0-3.0 of La, 0.0-3.0 of Ti at 300÷700°C, including separation of liquid and solid transformation products, followed by burning oxidation of gaseous products and addition of the obtained mix of carbon dioxide and water vapour to the source hydrocarbons at the rate of 2.0÷20.0 mass %. Before the raw material intake the reaction system is flushed by an inert gas (nitrogen), starting from 300°C and to the transformation temperature. Hydrocarbons used are alkanes, olefins or alkane olefin mixes C2-C15 without preliminary separation into fractions. Gaseous transformation products undergo burning and complete oxidation in the presence of an oxidation catalyst of vanadium/molybdenum contact piece, V2O5/MoO3. To sustain continuous process two identical reactors are used, where the catalyst is transformed and recovered in turns.
EFFECT: longer working transformation cycle due to the continuous process scheme; higher yearly output of aromatic hydrocarbons; reduced energy capacity and improved ecology of the process.
SUBSTANCE: invention describes zeolite-containing catalyst for transformation of aliphatic hydrocarbons C2-C12 to a mix of aromatic hydrocarbons or high-octane gasoline component containing zeolite ZSM-5 with silicate module SiO2/Al2O3=60-80 mol/mol and 0.02-0.05 wt % of residual sodium oxide content, zeolite structural element, promoter and binding component, with zirconium or zirconium and nickel oxides as zeolite structural component, and zinc oxide as promoter, at the following component ratio (wt %): zeolite 65.00-80.00; ZrO2 1.59-4.00; NiO 0-1.00; ZnO 0-5.00; Na2O 0.02-0.05, the rest being binding component. Also, a method for obtaining zeolite-containing catalyst is described, which involves mixing reagents, hydrothermal synthesis, flushing, drying and calcinations of sediment. The reaction mix of water solutions of aluminum, zirconium and nickel salts, sodium hydroxide, silicagel and/or aqueous silicate acid, inoculating zeolite crystals with ZSM-5 structure in Na or H-form, and structure-former, such as n-butanol, is placed in an autoclave, where hydrothermal synthesis is performed at 160-190°C for 10-20 hours with continuous stirring; the hydrothermal synthesis over, Na-form pulp of the zeolite is filtered; the obtained sediment is flushed with domestic water and transferred to salt ion exchange by processing by water ammonium chloride solution with heating and stirring of the pulp; the pulp obtained from salt ion exchange is filtered and flushed with demineralised water with residual sodium oxide content of 0.02-0.05 wt % on the basis of dried and calcinated product; flushed sediment of ammonium zeolite form proceeds to zinc promoter introduction and preparation of catalyst mass by mixing of ammonium zeolite form modified by zinc and active aluminum hydroxide; obtained catalyst mass is extruded and granulated; the granules are dried at 100-110°C and calcinated at 550-650°C; calcinated granules of zeolite-containing catalyst are sorted, ready fraction of zeolite-containing catalyst is separated, while the granule fraction under 2.5 mm is milled into homogenous powder and returned to the stage of catalyst mass preparation. The invention also describes method of transformation of aliphatic hydrocarbons to high-octane gasoline component or a mix of aromatic hydrocarbons (variants), involving heating and passing raw material (gasoline oil fraction direct sublimation vapours or gas mix of saturated C2-C4 hydrocarbons) through stationary layer of the aforesaid catalyst.
EFFECT: reduced number of components and synthesis stages of zeolite-containing catalyst; increased transformation degree of raw material; improved quality and yield of target products with the said catalyst.
4 cl, 8 tbl, 12 ex