A method of processing organochlorine waste by method of hydrogenolysis
(57) Abstract:The invention relates to a method of processing organochlorine waste by method of hydrogenolysis. The process is conducted in the presence of heterogeneous catalysts containing palladium at 250-350°C. the Hydrogenolysis is carried out in an environment of transformer oil AMT-300 or vaseline oil when it is 10-20-fold excess relative to the weight of organochlorine wastes. When the molar ratio of hydrogen : organochlorine waste, equal to 20-40 : 1, with the further separation of the gaseous products and recycle solvent containing unreacted waste. As a result of processing of organochlorine wastes receive the mixture of products whose disposal is not straightforward. table 1. The invention relates to the technology of organic synthesis, in particular, to methods for organochlorine waste production.A method of refining organochlorine waste method chlorinolysis (L. N. Zanaveskin, C. A. Averianov, Y. A. Traeger. Prospects for the development of processing methods halogenorganics waste. Regularities of catalytic hydrogenolysis galogensoderjasimi compounds. // USP, T. 65, No. 7, 1996).However, the (up to 500-600oC) and is associated with the formation of large quantities of hydrogen chloride and carbon tetrachloride, production should be phased out under the Montreal Protocol in connection with the prohibition of the release of ozone-depleting products.In addition, high-temperature chlorination followed by education (along with perchloroethane) highly toxic products: hexachloroethane, hexachlorobenzene and Hexachlorobutadiene. Burning them difficult, therefore a significant part of their being buried.The closest way to the same destination to the claimed invention on the totality of symptoms is the method of processing organochlorine waste by method of hydrogenolysis in the presence of heterogeneous catalysts containing platinum group metals at a temperature of 250-350oC (L. M. Kartashov, T. C. Chernysheva, L. N. Zanaveskin, Y. A. Traeger, I. N. Prokhorov. Processing of organochlorine wastes method of hydrogenation. // Chemical industry, 1996, N 6).For the reason that impede the achievement of specified following technical result when using the known method is:
- difficulty industrial the deposits on the surface of the catalyst carrier resinous and cocoabased the reaction products of the polymerization of unsaturated hydrocarbons, formed during gas-phase catalytic hydrogenolysis, and the need for repeated regeneration of the catalyst.The task of the claimed invention to provide an industrial method for processing organochlorine wastes by catalytic hydrogenolysis.One of the most acute problems of the creation and organization of low-waste, environmentally friendly production halogenoalkanes products is the processing and disposal of such facilities.Unpleasant feature of organochlorine wastes is that they are all xenobiotics and nature has no natural means of dealing with them. At the same time, not every way of turning halogenorganics compounds can be used for recycling, which was discussed above.The most versatile and promising method of processing organochlorine waste is considered hydrogenolysis, as this method best meets the requirements of the waste processing techniques, such as:
- renewable carbon-containing raw material or commercial value of the resulting products;
- the efficiency of the processing is composed as a result of processing waste highly toxic substances.During implementation of the invention can be obtained by technical result, which is expressed in the possibility:
- processing of organochlorine waste on an industrial scale;
- processing a wide range of organochlorine products;
- obtain the target products, which can be returned to the process cycle.The above technical result is achieved by the feature of the method of processing organochlorine wastes, namely, that the hydrogenolysis is carried out in an inert high-boiling hydrocarbon solvent for 10-20 times its excess in relation to the mass of chlorinated organic wastes and at a molar ratio of hydrogen and chloro-organic waste, equal to 20-40: 1, with the further separation of the gaseous reaction products by the known methods and recycling of unreacted waste solvent. As the inert high-boiling hydrocarbon solvent used liquid mixture alifaticheskih, aromatic and cyclic hydrocarbons with a boiling range of 250-350oC (transformer oil AMT-300, liquid paraffin).Processing of organochlorine wastes guy is Itachi this process on an industrial scale, because the solvent to regenerate the catalyst by washing with the surface of the catalyst carrier resinous and cocoabased products.The way hydrogenolysis real organochlorine waste products of epichlorohydrin, perchloroethane and vinyl chloride in the liquid phase is carried out in a flow type reactor with a fixed bed of catalyst, Proektirovanie by well-known methods. As catalyst using alumina and activated carbon impregnated with salts of palladium and palladium content of 0.4-1.8 wt.% respectively.Hydrogen and a solution or a solution and fine suspension of organochlorine waste 10-20-fold excess of the high-boiling solvent relative to the weight of organochlorine waste at a molar ratio of hydrogen: organochlorine waste 20-40:1 concurrent threads is served in the upper part of the reactor. The temperature of the process 250-350oC.The reaction products are a mixture of chlorohydrocarbons in the solvent, unreacted hydrogen and vydelevshimsya hydrogen chloride is removed from the bottom of the reactor and subjected to separation of the known methods.High-boiling ug the satisfactory results and great availability for experimental validation was used catalytic system based on palladium and aluminum oxide or activated charcoal.The method is confirmed by examples.Example 1. In a flow type reactor with a fixed bed catalyst containing 0.4% palladium on aluminum oxide serves organochlorine waste in the amount of 2.5 g/h (0,0187 mol/h) in an inert high-boiling solvent in the ratio of organochlorine waste:solvent 1:10.As organochlorine waste use waste production of vinyl chloride of the following composition: 1,2-dichloroethane - 12,2%; high-boiling - 72,9%, including 1,1,2-trichloroethane - 42,4%, perchlorethylene by 14.4%, 1,1,2,2 - and 1,1,1,2-trichloroethane and 14.9% (Composition A).As the inert high-boiling solvent used transformer oil AMT 300.Hydrogen is fed into the parallel reactor in a molar ratio to organochlorine deviation equal to 1: 40. The hydrogenolysis is carried out at a temperature 295-300oC.Conversion of the original chlorohydrocarbons is 88,7%.The composition of the obtained products: ethane, and ethylene - 0.35 g/h (0,012 mol/h); ethyl chloride and vinyl chloride - 0.28 g/h (0,0045 mol/h) of hydrogen chloride 1,67 g/h (0,045 mol/h); unreacted waste - 0,20 (0,0015 mol/h).Example 2. Analogously to example 1, the hydrogenolysis is carried out at a temperature of 250o<>/P>Example 4. Analogously to example 1, during use as a catalyst activated carbon content of 1.8% palladium.Example 5. Analogously to example 1, the hydrogenolysis is carried out at 20-fold excess of hydrogen.Example 6. Analogously to example 1, is subjected to hydrogenolysis organochlorine waste products of epichlorohydrin following composition (Composition B): dichloropropan - 36,4%, dichloropropene - 13,5%, monochloropropane - 18,5%, trichlorpropane - 26,0%, high-boiling (osmole) is 5.6%.Example 7. Analogously to example 1, is subjected to hydrogenolysis waste of perchloromethane of the following composition (Composition B): hexachlorobenzene - 35,5%, Hexachlorobutadiene - 36,3%, hexachlorethane at 24.1%, osmole of 4.1%.The results of the examples are given in the table.The use of the proposed method of processing organochlorine waste by method of hydrogenolysis gives it an industrial scale.Unlike the method of disposal of waste organochlorine production (prototype), where the process was used waste pre-clarified, the preferred method involves the processing of real waste in a wide range of both composition and Peabody organochlorine waste is the option of turning them into a mixture of products, disposal of which is not straightforward. A method of processing organochlorine waste by method of hydrogenolysis in the presence of heterogeneous catalysts containing palladium at 250 - 350oC, wherein the hydrogenolysis is carried out in an environment of transformer oil AMT-300 or vaseline oil during its 10 - 20-fold excess relative to the mass of chlorinated organic wastes and at a molar ratio of hydrogen : organochlorine waste, equal to 20-40 : 1, with the further separation of the gaseous products and recycle solvent containing unreacted waste.
FIELD: organic synthesis catalysts.
SUBSTANCE: catalyst is prepared from allyl chloride production wastes comprising 30-50% 1,3-dichloropropenes, 30-60% 1,2-dichloropropane, and 3-5% 1,2,3-trichloropropane, which are treated at 5-10°C with 30-50% dimethylamine aqueous solution in such amount as to ensure stoichiometric ratio of dimethylamine with respect to 1,3-dichloropropenes. Resulting mixture is held at 20-25°C for 0.5-1.0 h and then 40-44 sodium hydroxide solution is added in stoichiometric amount regarding dimethylamine, after which clarified waste is added to dimethylamine at 60-70°C and stirring in amount ensuring stoichiometric ratio of dimethylamine to 1,3-dichloropropenes contained in clarified waste. Mixture is aged for 2-3 h, organic phase is separated, and remaining interaction phase is supplemented by C1-C4-alcohol or benzyl alcohol at alcohol-to-dimethylamine molar ratio 1:(1-3).
EFFECT: reduced expenses on starting materials.
2 cl, 3 ex
FIELD: chemical industry, in particular method for production of value monomer such as vinylchloride.
SUBSTANCE: claimed method includes passing of reaction mixture containing dichloroethane vapor trough catalytic layer providing dehydrochlorination of dichloroethane to vinylchloride. Catalyst has active centers having in IR-spectra of adsorbed ammonia absorption band with wave numbers in region of ν = 1410-1440 cm-1, and contains one platinum group metal as active component, and glass-fiber carrier. Carrier has in NMR29Si-specrum lines with chemical shifts of -100±3 ppm (Q3-line) and -110±3 ppm (Q4-line) in integral intensity ratio Q3/Q4 from 0.7 to 1.2; in IR-specrum it has absorption band of hydroxyls with wave number of ν = 3620-3650 cm-1 and half-width of 65-75 cm-1, and has density, measured by BET-method using argon thermal desorption, SAr = 0.5-30 m2/g, and specific surface, measured by alkali titration, SNa = 10-250 m2/g in ratio of SAr/SNa = 5-30.
EFFECT: method with high conversion ratio and selectivity.
3 cl, 2 ex
FIELD: industrial organic synthesis.
SUBSTANCE: gas-phase thermal dehydrochlorination of 1,2-dichloroethane is conducted in presence of hydrogen chloride as promoter dissolved in feed in concentration between 50 and 10000 ppm.
EFFECT: increased conversion of raw material and reduced yield of by-products.
4 cl, 1 tbl, 8 ex
FIELD: chemistry of organochlorine compounds, chemical technology.
SUBSTANCE: method involves treatment of 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)-ethane with solid calcium hydroxide or a mixture of solid calcium hydroxide and solid sodium hydroxide with the content of sodium hydroxide in mixture 30%, not above, in the molar ratio 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)-ethane to alkali = 1:(1.5-1.75) at heating in the presence of catalyst. As catalysts method involves benzyltrialkyl ammonium halides, preferably, benzyltriethyl ammonium chloride or benzyltrimethyl ammonium bromide, tetraalkyl ammonium halides, preferably, tetrabutyl ammonium bromide taken in the amount 0.0005-0.005 mole. Invention provides the development of a new method for preparing 1,1-dichloro-2,2-bis-(4-chlorophenyl)-ethylene allowing to enhance ecological safety of technological process and to improve quality of the end product.
EFFECT: improved method preparing.
2 cl, 15 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to a method for preparing vinyl chloride monomer and to a catalyst sued in catalytic preparing vinyl chloride monomer from flows comprising ethylene. Method for preparing vinyl chloride from ethylene is carried out by the oxidehydrochlorination reaction. Method involves combining reagents including ethylene, the source of oxygen and chlorine in the catalyst-containing reactor at temperature 350-500°C and under pressure from atmosphere to 3.5 MPa, i. e. under conditions providing preparing the product flow comprising vinyl chloride and ethylene. Catalyst comprises one or some rare-earth elements under condition that the atomic ratio between rare-earth metal and oxidative-reductive metal (iron and copper) is above 10 in the catalyst and under the following condition: when cerium presents then the catalyst comprises additionally at least one rare-earth element distinctive from cerium. Ethylene is recirculated from the product flow inversely for using at stage for combining reagents. Invention proposes a variant for a method for preparing vinyl chloride. Also, invention proposes variants of a method for catalytic dehydrochlorination of raw comprising one or some components taken among ethyl chloride, 1,2-dichloroethane and 1,1,2-trichloroethane in the presence of catalyst. Catalyst represents the composition of the formula MOCl or MCl3 wherein M represents a rare-earth element or mixture of rare-earth elements taken among lanthanum, cerium, neodymium, praseodymium, dysprosium, samarium, yttrium, gadolinium, erbium, ytterbium, holmium, terbium, europium, thulium and lutetium. The catalytic composition has the surface area BET value from 12 m2/g to 200 m2/g. Invention provides simplifying technology and enhanced selectivity of the method.
EFFECT: improved conversion method.
61 cl, 8 tbl, 32 ex
FIELD: industrial organic synthesis.
SUBSTANCE: invention relates to perfluoroolefins production technology, notably to heaxafluorobutadiene CF2=CF-CF=CF2. Process comprises reaction of 1,2,3,4-tetrachlorohexafluorobutane with zinc in aqueous medium at 30 to 90°C. Reaction is carried out by metering 1,2,3,4-tetrachlorohexafluorobutane into reaction vessel containing zinc and water, while simultaneously desired product formed is recovered. Advantageously, process is conducted in presence of promoter selected from acids such as sulfuric acid and hydrochloric acid, soluble weak base salts such as zinc and ammonium halides, interphase transfer catalysts such as quaternary ammonium salts, quaternary phosphonium salts, tetrakis(dialkylamino)phosphonium salts, and N,N',N"-hexaalkyl-substituted guanidinium salts, or mixtures of indicated substances.
EFFECT: increased purity of heaxafluorobutadiene and simplified technology.
4 cl, 7 ex