Methods of producing ethylene oxide and ethylene glycol |
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IPC classes for russian patent Methods of producing ethylene oxide and ethylene glycol (RU 2462461):
    
 Method of removing poly(propylene oxide) from propylene oxide through membrane separation / 2452731
Invention relates to a method of removing poly(propylene oxide) from propylene oxide through membrane separation. The membrane used is a nonporous membrane made from polysiloxane containing repeating units of formula: -Si (R) (R')-O-, where R and R' denote hydrogen or a hydrocarbon group selected from alkyl, aralkyl, cycloalkyl, aryl and alkaryl.
 Ethylene oxide synthesis device and method / 2399617
Invention relates to a vessel which is used in an ethylene oxide extraction/distillation system, ethylene oxide extraction/distillation system and a method of extracting ethylene oxide from an aqueous liquid - ethylene oxide absorbent. Distillation and reabsorption processes during extraction of ethylene oxide from an aqueous absorbent are usually carried out separately. The invention discloses a single vessel for extracting and distilling ethylene oxide, which is divided by an inner partition wall into separate sections where reabsorption and distillation take place.
Propene epoxidation method / 2388755
Present invention relates to a propene epoxidation method which involves reaction of propene with hydrogen peroxide in the presence of methanol as a solvent and titanium zeolite catalyst. The proposed method involves separation of propylene oxide from the reaction mixture to obtain a mixture (Ma), containing methanol, water, at least one carboxylic acid and at least one carbonyl compound. At least one carboxylic acid contained in Ma is at least partially neutrailised by adding a base to mixture Ma to form a mixture Mb. Methanol is separated through distillation from mixture Mb and repeatedly partially used at the propene and hydrogen peroxide reaction step. The said method optionally involves a hydrogenation step before the neutralisation step.
 Olefin epoxidation method with improved energy balance / 2371439
Present invention relates to an olefin epoxidation method, which involves: (a) reacting olefin with hydrogen peroxide on a titanium zeolite catalyst in the presence of methanol as a solvent, at least, in a two-step reaction, obtaining a mixture (M-a), containing olefin oxide, unreacted olefin, methanol and water, where, at least, between the two reaction steps, olefin oxide is separated by distillation; (b) separation of unreacted olefin from mixture (M-a) through distillation, obtaining a mixture (M-bi) which contains at least 80 wt % olefin and a mixture (M-bii), containing methanol, water and, at least, 7 wt % olefin oxide; (c) separation of olefin oxide from mixture (M-bii), in at least a single distillation step, obtaining a mixture (M-ci) which contains at least 99 wt % olefin oxide, and a mixture (M-cii) which contains water and at least 55 wt % methanol; (d) separation of methanol from mixture (M-cii) in at least a single distillation step, obtaining a mixture (M-di), containing at least 85 wt % methanol and up to 10 wt % water, and a mixture (M-dii), containing at least 90 wt % water; containing at least 85 wt % methanol, upper vapour flow (Td), obtained from at least a single distillation column, used in step (d), used for at least partial operation of at least one evaporator, used in at least one distillation column, used in at least one of the stages (a), (b) and (c).
 Propylene oxide recovery from propylene oxide and methanol mixture / 2357963
Invention refers to method of propylene oxide recovery from mixture (M) containing 5 to 15 weight percent and 50 to 85 methanol weight percent. The disclosed method involves (i) introduction of specified mixture (M) to an extractive distillation column; (ii) additional introduction of polar solvent to specified extractive distillation column; (iii) predistillation of propylene oxide from specified extractive distillation column at bottom temperature 40 to 70°C and pressure 300 to 750 mbar. The polar solvent is water in amount 2 weight percent of mixture (M) or less.
 Isolation of propylenoxide from mixture, containing propylenoxide and methanol / 2341519
Method includes (i) introduction of said mixture (M) into extractive distillation column; (ii) additional introduction of extracting solvent into said extractive distillation column; (iii) distillation of main propylenoxide distilate from said extractive distillation column in form of upper flow; (iv) diversion of low-part flow from said extractive distillation column; (v) compression of upper flow, obtained in (iii), by means of at least, one compressor, in order to produce compressed steam.
 Method of purifying crude propene-oxide / 2330032
Invention relates to method of purifying crude propene-oxide, which contains methanol and acetaldehyde, by carrying out continuous extractive distillations with the use of an extraction solvent, which reduces the volatility of methanol, and supply of the connection, which contains the unsubstituted group NH2 capable of interacting with acetaldehyde, into the distillation column at a level higher than the point of entry of the crude propene-oxide, obtaining purified propene-oxide, which contains less than 100 parts/million of methanol and less than 100parts/million acetaldehyde. Also described is the method of catalytic epoxidation of propene, which includes this stage of purification.
 Method of propylene oxide preparation / 2324689
Suggested method includes the following stages: (i) interaction of propene and hydrogen peroxide in the presence of ceolite catalyst, and at least of one dissolvent until mixture (G0) is obtained, which contains propylene oxide, non-reacted propene and dissolvent; (ii) isolation of propene out of the mixture (G0) until mixture (G1) is obtained, which contains propylene oxide and at least one dissolvent; (iii) isolation with distillation at the pressure of less than 1.013 bar of propylene oxide out of mixture (G1) with application of distillation column, at that column lower part flow and secondary steam flow that mainly contains propylene oxide are received; (iv) compression of secondary steam flow received at stage (iii), with the help of at least one compressor until compressed secondary flow is obtained; (v) condensation of secondary steam flow received at stage (iv) during repeated use of at least part of condensation heat. Additionally the method may include stage (vi) of cooling condensate received at stage (v) with repeated use of cooled condensate part as reflux in distillation column used at stage (iii).
 Method of recuperation of heat / 2300530
Proposed method includes absorption of ethylene oxide from circulating gas flow by washing the gas in scrubber. Washed flow of circulating gas is brought in contact with hot absorbing carbonate solution for absorption of CO2 and flow of circulating gas after absorption of CO2 returning it to ethylene oxide production cycle; proposed method includes also bringing the said washed circulating gas flow in contact with heated liquid after removal of ethylene oxide at first contact stage, transferring the preheated circulating gas to stage of absorption by hot carbonate for removal of CO2, cooling the said circulating gas from stage of absorption by carbonate and removal of carbonate from it by bringing it in contact with said liquid from first contact stage at second contact stage after cooling this liquid, transferring the liquid from second contact stage to first contact stage and transferring the cooled circulating gas from second contact stage to reaction system for obtaining the ethylene oxide.
Method for interaction of organic compound with hydroperoxide / 2290400
invention relates to a method for interaction of an organic compound with hydroperoxide. Invention describes a continuous method of interaction of organic compound comprising at least one C-C-double bond with hydroperoxide in the presence of a catalyst. Method involves interaction of organic compound at the reaction step (R1) under the range of the own pressure below 100 bars, temperature in the range 0-120°C and in the molar ratio of reacting organic compound to hydroperoxide in the range 0.7-20 with hydroperoxide in the presence of a zeolite-containing catalyst to yield at least one flow of the product (P1). Then at least one flow of the product (P1) is fed to intermediate treatment (Z1) wherein (Z1) forms at least one the hydroperoxide-containing product flow (PZ1) and wherein the intermediate treatment represents distillation separation of hydroperoxide from at least one the product flow (P1) or addition of a base to at least one the product flow (P1) and at least one the product flow is fed to at least in the reaction step (R2) wherein under pressure in the own pressure up to 100 bars, temperature in the range 0-120°C and in the molar ratio of the reacting organic compound to hydroperoxide in the range 0.7-20 hydroperoxide is subjected for interaction with an organic compound in the presence of a zeolite-containing catalyst to yield at least one the product flow (P2) wherein at least one of reaction steps (R1) and (R2) the method involves using the reactors system comprising at least two reactors joined in parallel. Also, invention describes a device for carrying out the interaction of an organic compound with hydroperoxide.
 Method of hydroxidation using catalyst produced from gold cluster complex / 2445159
Invention relates to olefin hydroxidation catalysts. Proposed catalytic composition for production of olefin oxide by olefin hydroxidation comprises gold nanoparticles deposited on particles of nanoporous titanosilicate carrier. Note here that said catalyst is obtained by method including deposition of cluster complex gold-ligand on nanoporous titanosilicate carrier at minus 100°C to 300°C to produce catalyst precursor, and heating at not over 50-800°C and/or chemical treatment of catalyst precursor for 15 min to 5 h to form catalyst. Invention covers also the method of producing olefin oxide comprising bringing olefin with, at least, three carbon atoms in contact with oxygen in the presence of hydrogen and catalyst with above described composition. Note here that said contact is realized at 160°C and lower that 300°C and pressure varying from atmospheric pressure to 3549 kPa (500 psi). It covers also catalyst precursor composition including cluster complex ligand-gold deposited on particles of nanoporous titanosilicate carrier.
 Calcination in inert gas in presence of low-concentration oxidising component / 2411997
Invention relates to an improved method of producing silver catalysts used in gas phase synthesis of ethylene oxide from ethylene and oxygen. Described is a method of producing a catalyst, involving saturation of an inert substrate with a solution which contains a catalytically effective amount of a compound which contains silver, a promoting amount of a compound which contains a transition metal, calcination of the saturated substrate by heating at temperature ranging from approximately 200°C to approximately 600°C for a period of time sufficient for reducing the silver compound to metallic silver, and for decomposition and removal of almost all organic substances; heating is carried out in an atmosphere which includes a combination of an inert gas and from approximately 10 parts per million to approximately 500 parts per million of a gas which contains an oxygen-containing oxidising component. The invention describes a catalyst produced using said method, and a method of oxidising ethylene to ethylene oxide using molecular oxygen in gaseous phase in the presence of the obtained catalyst in a fixed layer in a tubular reactor.
Method of preparing catalyst carrier and its use in production of catalysts / 2408424
Invention relates to composition intended for producing catalyst carrier, to method of producing said carrier, to catalyst and method of its production, and to method of ethylene oxidation in its presence. Proposed composition comprises the mix of at least one alpha aluminium oxide with mean particle size of about 5 mcm or larger in amount of about 20 wt % to about 40 wt % of total content of aluminium oxide in this composition; at least, one hydrated precursor of alpha aluminium oxide in amount of about 60 wt % to about 80 wt % total content of aluminium oxide in this composition; binder and foaming agent. Invention covers also method of producing catalyst carrier comprising producing above described composition and heating it to convert into porous melted structure, method of producing catalyst comprising deposition of catalytically efficient amount of silver on said catalyst carrier, and catalyst produced as described above. It covers also the method of oxidising ethylene to ethylene oxide comprising gas-phase oxidation of ethylene by molecular oxygen in tubular reactor with stationary layer in the presence of produced catalyst.
 Nanoscale restructuring of aluminium oxide support surface and alkene oxide synthesis catalyst / 2402376
Invention relates to a support, a method of preparing said support, a catalyst for epoxidation of olefins having said support and a method of oxidising ethylene to ethylene oxide. The invention describes a support for a catalyst used in epoxidation of olefins which has an inert heat-resistant solid substrate having a surface and several projections coming out of the surface which are detected at scanning frequencies in the interval from approximately 250 cycles/micrometre or more. Described is a method of making such a carrier involving processing the surface of the substrate in order to obtain several projections on the surface of the substrate. The invention describes a catalyst for epoxidation of olefins having the support described above and a catalytically effective amount of silver, and a method of oxidising ethylene to ethylene oxide using the said catalyst.
Method of making catalyst support / 2395338
Present invention relates to catalysts supports which are used as supports for metal and metal oxide components of catalysts used in different chemical reactions. The invention describes a catalyst support precursor which contains a mixture of alpha aluminium oxide and/or transition aluminium oxide; binder; and a solid sponging agent which expands or releases gas when sufficient heat is supplied. A method of making a catalyst support is described, which involves preparation of the catalyst support precursor described above and water, moulding the obtained precursor into a structure, heating the said structure for a sufficient time and at temperature sufficient for formation of a porous structure as a result of the effect of the sponging agent, and then heating the porous structure for a sufficient time and at temperature sufficient for melting of the porous structure, thereby forming a porous catalyst support. A catalyst preparation method is described, which involves the above described steps for making a porous catalyst support and depositing a catalytically effective amount of silver onto the surface of the support. Described also is a catalyst made using the method described above and a method for oxidising ethylene in the presence of the said catalyst. Described also are catalyst support precursors which contain alpha aluminium oxide and/or transition aluminium oxide, binder, a sponging agent and/or talc or a water-soluble titanium compound, and methods of making the said precursors.
 Method of producing ethylene oxide / 2378264
Invention relates to a method of producing ethylene oxide by bringing a mixture fed into an epoxidation reactor, which may contain ethylene, oxygen, carbon dioxide and water in a defined concentration, into contact with a highly selective epoxidation catalyst containing a promoter amount of rhenium. Contacting the mixture fed into the epoxidation reactor is done under epoxidation reaction conditions at reaction temperature below 260°C. The said mixture contains carbon dioxide in concentration less than 2 mol % of the entire mixture and concentration of water in the mixture of at most 1.5 mol % of the entire mixture. Observation of the combination of the said conditions for carrying out the epoxidation process improves operational properties of the epoxidation catalyst, for example increased stability, selectivity and activity of the catalyst.
 Enhanced carriers from aluminium oxide and silver-based catalysts for producing alkylene oxides / 2372342
Invention relates to methods of producing carriers from aluminium oxide which have desirable properties when used as carriers for silver-based catalysts. The method of making a modified catalyst carrier for vapour-phase epoxidation of alkene involves a) saturation of a moulded carrier made from alpha aluminium oxide, which has been burnt and optionally subjected to other types of processing which provide for preforming, as part of the preforming process with at least one modifier, chosen from silicates of alkali metals and silicates of alkali-earth metals; b) drying said saturated carrier and c) burning said dried carrier at temperature not below 800°C. To obtain the catalyst, the method additionally involves stage d) where silver catalytic material is deposited on the said dried carrier. The invention also relates to epoxidation reactions, carried out in the presence of catalysts given above.
 Method of producing olefin oxide, method of using olefin oxide and catalytic composition / 2361664
Present invention relates to methods of producing a catalytic composition, to the method of producing olefin oxide and method of producing 1,2-diol or 1.2-diol ether. Described is a method of producing a catalytic composition, involving deposition of silver on a carrier and deposition of a promoter - alkali metal on the carrier. The alkali metal contains potassium in amount of at least 10 mcmol/g and lithium in amount of at least 1 mcmol/g in terms of mass of catalytic composition. The alkali metal is deposited on the carrier before depositing silver, at the same time or after depositing silver on the carrier. Described is a method of producing a catalytic composition, involving use of potassium as a promoter in amount of at least 10 mcmol/g and sodium in amount of at least 5 mcmol/g in terms of mass of the catalytic composition. Description is given of a method of producing olefin oxide by reacting olefin, which has at least three carbon atoms, with oxygen in the presence of a catalytic composition, obtained using the method described above. This invention also pertains to the method of producing 1,2-diol or 1,2-diol ether using olefin oxide, obtained using the said method.
 Method of obtaining alkylene oxide using gas-phase promoter system / 2360908
Additive to reaction of epoxidation represents two-component gas-phase promoter system, which contains chlorine-containing component (for instance, ethyl chloride, methyl chloride, vinyl chloride and ethylene dichloride) and nitrogen-containing component from group of nitrogen monoxide and other compounds able to form in reaction conditions at least one gaseous, increasing efficiency, member of pair of oxidation-reduction semi-reaction, including NO, NO2, N2O3 or N2O4. Quantity of each component of said gaseous promoter is taken in such way as to support ratio N* to Z* within the interval from 0.4 to 1, where N* represents equivalent of nitrogen monoxide, in ppmv, ranging from 1 to 20 ppmv, and Z*=(ethyl chloride equivalent (ppmv))x100%/(ethane equivalent (mol %))x100, ranging from 5 to 40 ppmv. Said equivalents are determined depending on concentrations of nitrogen-containing component, chlorine-containing component and ethane or other hydrocarbon at reactor inlet in accordance with stated in i.1 of the formula.
 Catalysts for obtaining alkylene oxides, which have improved stability, efficiency and/or activity / 2360735
Described is catalyst for obtaining alkylene oxide by alkene epoxidation in steam phase, which contains applied by impregnation silver and at least one promoter on burnt heatproof solid carrier, and said carrier contains quantity of zirconium component, which is present in carrier mainly as zirconium silicate, and said heatproof carrier, with the exception of zirconium component at least on 95% by weight consists of aluminium alpha-oxide. Also described is method of said catalyst obtaining which includes: a) mixing of zirconium component, which is mainly present as zirconium silicate, with initial materials of carrier, which include aluminium oxide; b) burning of initial materials of carrier with added zirconium component at temperature less than 1540°C with formation of carrier, which includes aluminium alpha-oxide, where carrier includes zirconium component, present mainly as zirconium silicate; c) further deposition of silver and at least one promoter on carrier. In addition, described is method of catalyst application for alkyl oxide obtaining.
 Catalyst for hydrolysis of cellulose and/or reduction of products of hydrolysis of cellulose and method of producing sugar alcohols from cellulose / 2427422
Present invention relates to a catalyst for hydrolysis of cellulose or hydrolysis of cellulose and reduction of products of hydrolysis and a method of producing sugar alcohols from cellulose. Described is a catalyst for hydrolysis of cellulose and hydrolysis of cellulose and reduction of hydrolysis products in which a group 8-11 transition metal is deposited on a solid substrate. Described also is a method of producing sugar alcohols involving: hydrolysis of cellulose in the presence of the catalyst in a hydrogen-containing atmosphere at high pressure and reduction of the product of hydrolysis of cellulose.
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FIELD: chemistry. SUBSTANCE: according to the invention, a base is further added to one or more positions downstream the heat-removal section of an ethylene oxide absorber to main pH in the range of 5.5-9.5, in at least one region, where glycolic esters are hydrolysed to an organic acid and ethylene glycol. EFFECT: reduced corrosion of an ethylene oxide or ethylene glycol producing apparatus. 10 cl, 4 dwg
The technical field to which the invention relates The present invention relates to a method for production of ethylene oxide and method of producing glycol. The level of technology Ethylene oxide is mainly used as an intermediate compound for the manufacture ethylene glycols, but also to obtain ethoxylates, ethanolamines, solvents and glycol ethers. It is produced by direct oxidation of ethylene with oxygen or air. Ethylene and oxygen is passed over the catalyst with silver oxide, typically at a pressure of 10-30 Bar and a temperature of 200-300°C. the Reaction is exothermic and a typical reactor consists of a large interconnected bundles of several thousand tubes, which are filled with catalyst. The refrigerant is circulated around the reaction tubes, removing the heat of reaction, and allows you to control the temperature. The product stream from the reactor with ethylene oxide is fed into the absorber. The absorber has an initial heat section, where the flow of product in contact with the cooled, recirculated water stream, and the main solution is continuously added to the recirculating cooling flow. Such heat section is described in US 4822926. Water heat section is used to neutralize acidic compounds, such as acetic and formic acid, which may be formed in the reactor is. Another heat section is described in US 5336791. The gas stream passes through the heat section to the main section ethylenoxide absorber, in which purified water to the recovery of ethylene oxide. The resulting water stream that is saturated with ethylene oxide, called fat absorbent is sent to desorber of ethylene oxide. In ethylenoxide desorber ethylene oxide is desorbed and the concentration ethylenoxide flow, which is directed at the last stage of condensation, distillation and reabsorption. The remaining liquid, referred to as depleted absorbent, going again in ethylenoxide absorber. Ethylene oxide is a high degree of purification can be cooled, stored and shipped to consumers. Alternatively, the ethylene oxide produced may be directed to the synthesis of ethylene glycol. Ethylene glycol is typically produced by the interaction of ethylene oxide with excess water, usually at temperatures of 150-250°C. Under these conditions the reaction rate is high and does not require a catalyst. The reaction of ethylene oxide with water usually takes place with the formation of flow glycolic product consisting of 90% by weight of monoethylene glycol, the remainder mostly remains diethylene glycol, a bit of triethylene glycol and some higher homologues. The flow of the glycol is th product is passed through successive distillation columns with decreasing pressure to extract water, which returns to etilenglikolevye reactor. Mono-, di - and triethylene glycol are separated by vacuum distillation. Carbon steel is typically used for reaction vessels and pipelines to refineries for the production of ethylene oxide and ethylene glycol. In the Chapter "ethylene oxide" in encyclopedia of industrial chemistry, edited by Ullman (edition 1987) argues that the ethylene oxide does not cause corrosion, reactors and sections of the apparatus, which is ethylene oxide, usually made of low carbon steel. However, the inventors of the present invention investigated the corrosion of sections ethylenoxide/etilenglikolevykh devices and found the cause of this corrosion and thus find solutions that reduce the corrosion. The invention Thus, the present invention describes a method of producing ethylene oxide and optionally ethylene, consisting of the steps: (i) adding ethylene and oxygen in ethylenoxide reactor where ethylene and oxygen react with the formation of ethylene oxide, thus forming a stream of the reaction product; (ii) adding a flow of the reaction product in ethylenoxide absorber with heat section and the lower output of the absorption section, in which the flow of the reaction product interacts with recirculating water flow in teplootvodom the first section and the base, added to the recirculating aqueous solution, and in which the ethylene oxide is removed from the flow of the reaction product by absorption in water in the absorption section, thus forming a rich absorbent stream; (iii) adding a rich absorbent stream in ethylenoxide desorber, which enriched stream of absorbent ethylenoxide desorber, which enriched stream of the adsorbent is desorbed by steam, thereby obtaining a concentrated stream of ethylene oxide and depleted stream absorbent; (iv) recirculatory depleted stream of absorbent material ethylenoxide absorber; and (v) optionally, adding a concentrated stream of ethylene oxide to an end node of ethylene oxide, thereby obtaining purified ethylenoxide stream; and (vi) optionally, adding a concentrated stream of ethylene oxide, purified stream of ethylene oxide, or any other ethylenebisstearamide flow in the apparatus for obtaining ethylene glycol, to obtain ethylene glycol; in which method includes the additional step (vii) adding a base to one or more positions downstream from the heat section ethylenoxide absorber to maintain a pH in the range from 5.5 to 9.5 in at least one area where glycolic esters hydrolyzed to organic acids and Etiler ikola. Brief description of drawings Figure 1 is a schematic diagram showing a preferred variant of the method of obtaining of ethylene oxide according to the present invention. Figure 2 is a schematic diagram showing the preferred implementation of the method of producing ethylene glycol according to the present invention, which can be combined with the method shown in figure 1 to obtain ethylene oxide. Figure 3 is a graph showing the pH value in two different threads in ethylenoxide the device. Figure 4 is a graph showing the relationship between iron content and pH in the stream ethylenoxide apparatus. A detailed description of the invention The inventors investigated the corrosion occurring in ethylenoxide/etilenglikolem apparatus, and established the mechanism of occurrence of corrosion. They also established the reasons that explain why corrosion was observed in these devices, but was absent in the previous this study the level of technology. Finally, the inventors have developed techniques to reduce this corrosion. The inventors unexpectedly discovered that salts of organic acids, which are present in ethylenoxide absorber, interact with ethylene oxide to form the receiving glycol ethers. For example, salts of formic acid
(Sodium salt is formed in an alkaline solution, if is sodium hydroxide, if you use a different basis, then formed another salt). Data glycolic esters served downstream from ethylenoxide absorber to many points ethylenoxide/etilenglikolevykh apparatus, under certain conditions (usually in terms of lack of ethylene glycol and excess water) glycol esters hydrolyzed with the formation of organic acid and ethylene glycol, for example:
This receipt acid creates an acidic environment at any point in the apparatus where conditions are conducive to hydrolysis. Although the concentration of salts of organic acids in ethylenoxide absorber low, continuous hydrolysis of glycol ethers downstream from ethylenoxide absorber can lead to a gradual increase in the number of organic acids and the resulting decrease in pH. the pH may reach levels (e.g., below 4), which lead to corrosion of the device. In many ethylenoxide apparatus depleted absorbent is served in an open cooling chamber, but in order to protect the environment modern devices tend to be closed cooling systems. The inventors believe that in systems with open is the cooling of the camera most of the acid and glycol ethers evaporated and consequently by hydrolysis of glycol ethers downstream from ethylenoxide absorber formed small amounts of acid. In newer systems with closed cooling system acid and glycol ethers can't evaporate and the levels of acid and glycol ethers downstream from ethylenoxide absorber can locally increase so that there is a significant corrosion. In addition, in systems with open cooling systems, you must add a significant amount of make-up water in ethylenoxide absorber, because water loss occurs in the environment. This makeup water contains low levels of amines or other chemicals to control the pH of the water. Data amines or other chemical compounds can neutralize the acid formed by hydrolysis of glycol ethers, thus adding make-up water can reduce the effect hydrolysis of the ester and to reduce corrosion. In the case of closed cooling systems require much less make-up water and thus the concentration of amines or other chemical compounds will be lower and the neutralization of acids will decrease accordingly with the possibility of increased corrosion. One of the methods for reducing acid corrosion, it is the replacement of elements from carbon steel to stainless steel, but it is very expensive to replace and besides, even stainless steel is subject to corrosion when exposed to sufficient the full low pH for extended periods. The authors of the present invention have found that acid corrosion occurs where hydrolyzed glycol ethers and is able to reduce this corrosion by determining where flows the hydrolysis of glycol ethers and the addition of the base, respectively. This focused approach is easily accomplished once you have identified the areas where the hydrolysis of the ether, and you can continue using carbon steel, even in systems with closed cooling systems. To determine the mechanism of hydrolysis of glycol ether by the authors of the present invention, did not suspect that in areas downstream from the heat section ethylenoxide absorber pH may decrease and consequently cause corrosion. Due to the fact that the base or the acid is not added downstream from the heat section, significant changes in pH were not expected. The authors of the present invention unexpectedly discovered that downstream from the heat section ethylenoxide absorber can produce significant changes in pH, has established a mechanism that explains the changes in pH and have developed effective ways of preventing corrosion in ethylenoxide/etilenglikolevykh devices. Ballast gas, for example methane, is usually applied in order to make possible the operation p is high and oxygen levels without the formation of flammable mixtures. Inhibitor, such as monochloride or dichloroethane, can be used as the catalyst control work. Ethylene, oxygen, gas ballast and the inhibitor is preferably used as the recirculating gas in ethylenoxide reactor from ethylenoxide absorber. Ethylenoxide reactor is usually Novotrubny reactor with a fixed catalyst bed. The catalyst preferably is a fine silver and can be optionally a promoter metal on the supporting material, for example aluminium oxide. The reaction preferably proceeds at pressures above 10 bar and less than 30 bar and temperatures above 200°C and less than 300°C. A large part of the ethylene reacts with the formation of ethylene oxide, but some of the ethylene is oxidized completely, forming carbon dioxide and water. The flow of the reaction product is supplied in heat section ethylenoxide absorber. In the heat section of flow of the reaction product interacts with a recirculating aqueous solution and the substrate added to the recirculating aqueous solution. Preferably the base is an aqueous alkaline solution such as sodium hydroxide or potassium hydroxide, most preferably sodium hydroxide. The concentration of the alkaline solution is preferably from 5 to 50 wt.%, most preferably from 10 to 30 wt.%. Next, the gases pass through the absorber, where the ethylene oxide is recovered from the stream of the reaction product by absorption in water. Example ethylene absorber with heat section, described in US 4822926. In a preferred embodiment of the present invention drainage maloothodnoj section removed from heat section, preferably of the recirculating aqueous solution. Diversion of water from maloothodnoj section typically contains a low concentration of ethylene oxide, a low concentration of ethylene glycol and salts, such as sodium carbonate, and bicarbonate. Exhaust water is usually clean removal or recovery of ethylene oxide, for recovery of ethylene glycol and removal of impurities, such as salts of sodium. For example, tap water may be thus purified, as described in US 4822926: tap water served in a tubular reactor in which ethylene oxide is hydrolyzed to ethylene glycol, the resulting dilute aqueous solution of ethylene glycol is supplied to the evaporator, in which pariveda water, the resulting two-phase liquid system is fed to the centrifuge and the resulting centrifuged liquid phase is served in the glycol evaporator. Preferably, a pair of upper part ethylenoxide absorber is returned in re-cycle ethylenoxide reactor. Part of this re is cirkuliruyusiy gas preferably is evacuated through the gas from carbon dioxide and then returns to the recirculating stream. Outlet for recirculating gas is typically used for removal of accumulated inert gases such as ethane, argon and nitrogen and to remove impurities. The water stream is withdrawn from ethylenoxide reactor, enriched stream of absorbent served in ethylenoxide extractor. In a typical ethylenoxide extractor concentrated ethylenoxide stream exits through the top of the extractor, and the lean absorbent stream exits through the bottom of the extractor. Lean absorbent stream is returned to repeat the cycle in ethylenoxide absorber and preferably pre-cooled prior to its submission to ethylenoxide absorber. In a preferred embodiment of the present invention the cooling depleted absorbent stream is in a closed cooling system. Many systems known from the prior art, using open cooling system, but in order to protect the environment use a closed cooling system. In closed cooling systems is leaking corrosive as acid and glycol ethers are not removed by evaporation and glycol ethers can be either hydrolyzed with the formation of acids. However, in the method according to the present invention, the corrosion is prevented by addition of base to maintain a pH in the range from 5.5 to 9.5 in areas where flows hydro is of the esters. The method preferably includes a step of selection of the jet stream depleted adsorbent and the feed stream flow at site recovery of glycols from which to restore glycols. Glycol receive is usually low, but without removal of the jet stream content glycol recirculating depleted absorbent will increase. Concentrated ethylenoxide the thread that goes through the top ethylenoxide extractor additionally served to end ethylenoxide site, providing cleansing ethylenoxide flow. End node preferably consists of condensation, distillation and reabsorbtion nodes. Purified ethylenoxide stream can be cooled and sent to storage (ethylene oxide is usually kept under a layer of nitrogen at a temperature of approximately 10°C). The method according to the invention provides a number of stream containing ethylene oxide, and any of these threads can be obtained in etilenglikolem apparatus. In a typical EO/EG devices a number of different threads, including concentrated ethylenoxide stream, served in etilenglikolevye apparatus. It is possible but is not preferred for cleaned ethylenoxide flow in etilenglikolevye apparatus. Etilenglikolevye apparatus usually consists of the ethyl is a glycol reactor, layered evaporator, drying column and a distillation system. Etilenglikolevye the reactor preferably is a non-catalytic reactor where the ethylene oxide and water interact at a temperature of from 150 to 250°C and a pressure of from 30 to 40 atmospheres. Etilenglikolevye the reactor may be an alternative catalytic reactor. In non-catalytic reactor, preferably using an excess of water, for example in a molar ratio of ethylene oxide to water 22:1. Etilenglikolevye flow of product coming out etilenglikolevykh reactor, preferably served in a layered evaporative system, which removes excess water. Water removed from the multilevel evaporative system, preferably served in etilenglikolevye reactor. The water is preferably removed in the drying column. The water stream with a reduced content of ethylene glycol usually consists of from 70 to 95 wt.% monoethylene glycol, with the remains of diethylene glycol and triethylene glycol and served in a distillation system in which individual glycolic products are recovered with high purity. The base, which is added to the stage (vii), according to the invention preferably is an aqueous alkaline solution such as sodium hydroxide solution or potassium hydroxide. Hydrox the d potassium may be preferable because that potassium salts are more soluble than the salts of sodium and therefore pollute less such part etilenglikolevykh apparatus as heaters. However, sodium hydroxide is less expensive than potassium hydroxide, thus it may be preferable, especially if not formed diethylene glycol and triethylene glycol. The concentration of the aqueous alkaline solution is preferably from 5 to 50 wt.%, most preferably from 10 to 30 wt.%. The aqueous alkaline solution is a liquid that is added to liquids (i.e., it is not added to the substances participating in the reaction or the products in the gas phase). It may be preferable to use an organic base, generally Amin, to add sections etilenglikolevykh apparatus, especially in water that is returned from the evaporative system in etilenglikolevye reactor. However, the use of amines in ethylenoxide the drug is not preferred, because they can reduce the activity of the catalyst. The base is added to maintain a pH in the range from 5.5 to 9.5, preferably from 6 to 9 and most preferably from 6.5 to 8.5 at least in one area, where glycolic esters hydrolyzed in an organic acid and ethylene glycol. Adding sufficient base to maintain the pH above 5.5 is a guarantee that is about, even in spite of the flow of ether hydrolysis, acid corrosion of the apparatus does not leak. However, adding too much can cause an increase in pH above 9.5 and this is also undesirable. In ethylenoxide section of the device more than 9.5 pH can lead to carbonate stress corrosion. In etilenglikolevykh sections of the device more than 9.5 pH may affect the quality etilenglikolevykh product. pH in different parts of the apparatus may be controlled using various known methods and devices for measuring pH, including contour measuring pH and method of sampling. Preferably the pH range is from 5.5 to 9.5 in more than one area, where glycolic esters hydrolyzed to organic acid and ethylene glycol. In a preferred embodiment of the present invention the pH is maintained at 5.5 to 9.5, preferably from 6 to 9 and most preferably from 6.5 to 8.5 in all areas where glycolic esters hydrolyzed to organic acid and ethylene glycol. If in any area where glycolic esters hydrolyzed to organic acid and ethylene glycol, pH is not controlled, it is likely that in this area the acidity will continue to increase and will leak corrosion. The area where the glycol ether hydrolized is to the organic acid and ethylene glycol, can be defined using either chromatographic or spectroscopic methods or pH measurements. Using chromatographic or spectroscopic methods take samples from different parts of the apparatus. Samples analyzed using methods such as ion chromatography or infrared spectroscopy. These methods enable a person skilled in the art to determine the amount of glycol ethers and organic esters in the sample. By comparing the results for samples from different sites it is possible to see where increasing the content of organic acids and decreases the content of the glycol ether and thus to determine where the hydrolysis proceeds. By analyzing the pH is measured in pH in different parts of the apparatus, and areas where flows hydrolysis, determined by identifying areas where pH decreases. Prior to the present invention a specialist in the art could not assume about changing the pH of the stream downstream from the heat section ethylenoxide absorber and could not analyze the pH downstream from the heat section ethylenoxide absorber. The area where the hydrolysis of glycol ether may vary from device to device, depending on the device apparatus and conditions. Based on the study of several units, and the Torah of the present invention has identified a number of areas, where the most likely course of hydrolysis of glycol ether: ethylenoxide the absorber, evaporator and serial sections of drainage; site recovery of glycols (in which part of the depleted flow of the absorbent is supplied to the node) and etilenglikolem reactor, layered evaporator, drying column and etilenglikolevye distillation system. The base is added at one or more sites downstream from the heat section ethylenoxide flow. The plots and the number of bases that are added are identified in accordance with the requirements for the control of pH in one or more areas where flows the hydrolysis of glycol ether. The base is preferably added in many areas to give the ability to control pH in more than one area, where there is hydrolysis of glycol ether. Preferably the base is added in ethylenoxide extractor or in one or more areas downstream from ethylenoxide extractor. The authors of the present invention believe that the pH can kontrolirovat between a 5.5 and 9.5 in areas where there is hydrolysis of the ester by adding the base in one or more of the following areas: (a) the allotment maloothodnoj section, extracted from the heat partition in heat section, derived from ethylenoxide absorber, g is e removes the ethylene oxide (b) in the enriched stream of absorbent (C) in lean absorbent stream (g) in ethylenoxide desorber (d) if part of the flow of depleted absorbent is supplied to the node recovery glycol, in the part of the stream or at the very site recovery (e) if you are using EA leaf node, the enriched water and EA depleted streams emanating from EA end node (g) if the water is recycled from the (multilevel) evaporative system etilenglikolevye reactor, recirculating water at any point (C) in the water-depleted etilenglikolevykh the stream exiting the layered evaporator (and) in a distillation installation. Figure 1 shows a preferred variant of the method of the invention for obtaining ethylene oxide. Ethylene (1), oxygen (2), methane (3) and monochloramine (4) served in the recirculating gas stream (9), served in ethylenoxide reactor (5). Ethylenoxide reactor (5) is Novotrubny reactor with a fixed layer in which a tube filled with a silver catalyst on an aluminum substrate. The flow of the reaction product (6) out of the reactor (5)containing ethylene oxide, carbon dioxide, water and a small amount of impurities. The flow of the reaction product (6) is in heat section (7), and then in the absorber section (8) ethylenoxide is Barbara (7, 8). Surface gases in the absorber section (8) return re (9) ethylenoxide reactor (5). Part of the recycle gas stream (9) is given by (10) through the scrubber (11), which removes carbon dioxide from the recycle gas. In the heat of section (7) stream of the reaction product (6) is in contact with a recirculating aqueous solution (12). Sodium hydroxide (13) is added to the recirculating aqueous solution (12). The drain water heat section (14) is derived from the recirculating aqueous solution (12) and enters the site of removal of ethylene oxide (15), which may be a tubular reactor in which ethylene oxide is hydrolyzed to ethylene glycol, forming a dilute aqueous solution of ethylene glycol, or may be ethylenoxide desorber, where the ethylene oxide is extracted and sent back to ethylenoxide absorber (7,8). A dilute solution containing ethylene glycol (16), enters the evaporator (17), in which water and ethylene glycol warialda and restored. The remaining two-phase flow liquid mass (18) is transferred to a centrifuge (19) and resulting from the centrifugation of the liquid phase (20) moves in the glycol evaporator (21). As an alternative to the centrifuge (19) and the evaporator (21), the thread (18) can be transferred from the apparatus and processed in an independent process. Enriched by the flow of absorbent material (22), which is formed in ethylenoxide absorber (7, 8), served in ethylenoxide desorber (23). Depleted absorbent (24) from ethylenoxide of desorber (23) is returned again in ethylenoxide absorber (7, 8) through a cooling system (25). Concentrated ethylenoxide thread (26) of ethylenoxide of desorber (23) is served at the end ethylenoxide site (27), which produces purified ethylenoxide stream (28). The remaining water flows (29) can be sent back to the depleted stream absorbent (24), can be directed to glycolic site and/or can be directed into the waste water. Stream (30) depleted absorbent material (24) is glycolic node (31), forming a glycol stream (32). The base can be added in any area marked with an asterisk (*). This includes the rich absorbent stream (22), lean absorbent stream (24), part of the flow (30), streams (29), the flow of drainage water from heat section (14), a diluted solution of ethylene glycol (16), two-phase flow liquid mass (18) and glycol flow (32). The figure 2 shows the method of producing glycol which can be combined with the method of producing ethylene oxide, shown in figure 1. Any thread containing the ethylene oxide from ethylenoxide apparatus in figure 1 (for example, concentrated ethylenoxide stream (26), depleted by the OK absorbent (24), water flows (29)) can be added to etilenglikolevye reactor (33), which is a non-catalytic reactor tube type. Stream etilenglikolevykh product (34), leaving etilenglikolevykh reactor comes to multilevel evaporative system (35). Water is removed in a layered evaporator system (35) and served on etilenglikolevye reactor (33). Etilenglikolevye stream (37) is fed to the drying column (38), where additional water is removed. Etilenglikolevye stream (39), depleted water, is fed to a distillation unit (40), where individual glycolic products are extracted with a high degree of purity. The base can be added in any area marked with an asterisk (*). This includes evaporative system (35), water recycling (36) at any point, including containers for collection of waste water recycling system, in condensed etilenglikolem thread (37), into a drying column (38), etilenglikolem stream depleted in water (39). The inventors investigated the present invention in ethylenoxide/etilenglikolem apparatus mainly in accordance with figures 1 and 2. Figure 3 shows the pH depleted absorbent stream (24 in figure 1) and the pH of the flow from node removal glycol (32 in figure 1) in the upper part of the device during the year. During the beginning of the year pH outgoing on the eye was much lower than pH depleted stream of absorbent. It was flowed through the hydrolysis of glycol ethers in the node removal glycol. In June/July of large quantities of sodium hydroxide were added to the depleted absorbent and pH outgoing flow has increased significantly. This level of sodium hydroxide was excessive, resulting in undesirable increase of pH in the outgoing stream. From October sodium hydroxide was added in a controlled way. This increase in pH in the outgoing stream in a controlled way helped to reduce corrosion. Figure 4 shows how the iron content in the outgoing stream of glycol (32 in figure 1) alter the pH of the stream. The iron content increases with decreasing pH and is particularly high when the pH is below 6.5. The inventors experimentally found that high acidity in the outgoing stream (14 in figure 1) suggests that ethylene glycol is obtained in the lower part of the restoration sites that did not meet the technical requirements, having high amounts of esters. Adding an additional amount of sodium hydroxide solution to the output stream (14) has solved this problem. Adding sodium hydroxide solution in a recirculating water stream (36 figure 2) increased the pH of the water contained in the glycol system, and contributed to the reduction of corrosion. 1. SPO is about receipt of ethylene oxide and optionally ethylene glycol consisting of stages 2. The method according to claim 1, in which stage (vii) a base is added to the enriched absorbent stream, depleted stream of absorbent and/or ethylenoxide extractor. 3. The method according to claim 1 or 2, comprising a stage of removal of the outgoing water flow of heat partition and process water flow for removal or recovery of ethylene oxide to remove ethylene glycol and removal of impurities, such as salts of sodium. 4. The method according to claim 3, in which stage (vii) base type in the outgoing water stream either before or after it is processed for the removal or recovery of ethylene oxide. 5. The method according to claim 1, comprising a stage of cooling depleted absorbent stream in a closed cooling system. 6. The method according to claim 1, comprising the stage of taking of depleted absorbent stream and adding stream at site recovery of glycols, which are restored glycols. 7. The method according to claim 6, in which stage (vii) a base is added to the stream and/or the site restored what I glycol. 8. The method according to claim 1, in which etilenglikolevye the apparatus consists of etilenglikolevykh reactor, multilevel evaporative system, a drying column and a distillation system. 9. The method according to claim 8, in which water is returned again from the multilevel evaporative system etilenglikolevye reactor, and depleted water etilenglikolevye stream passes through the layered evaporator to a drying column, in which stage (vii) a base is added to water, returned again in etilenglikolevye reactor, depleted water etilenglikolevye stream and/or in a distillation system. 10. The method according to claim 1, wherein a base is added to the stage (vii), is a sodium hydroxide solution or potassium hydroxide solution.
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