The method shown in fig chloroaromatics connections
(57) Abstract:Usage: golozhabernyi aromatic compounds, the dehydrochlorination of chlorobenzene and chlorophenols, palladium catalyst. The invention: the hydrochlorination mono - or dichloropropane benzene or phenol are in the vapor phase fluidized bed of catalyst containing 0.5 wt.% palladium on aluminum oxide, in the presence of hydrogen diluted with an inert gas, at 80 to 150°C, molar ratio chloroaromatic compounds and hydrogen is 1 : 10. The content of hydrogen in the inert gas of 10 vol.%, the volumetric rate of feed of the mixture of the reactants in an inert gas 2000-25000 h-1exit 94 - 99%. 3 table. The invention relates to catalytic methods reductive dechlorination of highly dangerous organic substances and can be used for detoxification of chlorinated aromatic compounds, in order to obtain the target products. Thus obtained benzene and phenol are a valuable target products. Chlorine is removed in the form of hydrogen chloride and is used to produce hydrochloric acid.Widespread use of polychlorinated organic compounds (PHOS) in chemical industrial the person is associated with high toxicity PHOS, their carcinogenic and mutagenic activity, as well as cumulative accumulation in the food chain. In this regard, the urgent development of the detoxification processes of the most dangerous substances of this class.To destroy PHOS used and developed different methods, resulting in dechlorination of these substances or their complete destruction. The first group of methods dechlorination include: hydrolysis of PHOS alkaline solution poliatilenglikola dechlorination of PHOS metal oxides at a temperature of 200-800aboutC; dechlorination over molten aluminum or metallic sodium. These methods have a rather low efficiency.The second group includes more technological methods of catalytic and thermal oxidation in a furnace at a temperature of 600-1300aboutWith plasma-chemical decomposition and UV-ozone oxidation. However, detailed studies in recent years have shown that the oxidation processes as byproducts phosgene and especially dangerous chlorinated dibenzodioxin, which dramatically increase the environmental risk technologies oxidative dechlorination.Analysis of various options for detoxification chlorite is novillero dechlorination due to the fact, that the resulting products are always less dangerous than the original compounds.Known methods reductive dechlorination of chlorobenzene at 80aboutWith the damages of the catalysts Pd/Al2O3Rh/Al2O3Pd-Rh/Al2O3obtained by ion exchange or by impregnation of the support with solutions of PdCl2or RhCl2. The major transformation products are benzene and cyclohexane. The disadvantage of this method is low (less than 20%) the degree of transformation of chlorobenzene. In addition, dechlorination of other aromatic compounds has not been studied.The aim of the invention is to develop a method of complete dechlorination of dichlorbenzene, chlorophenols and dichlorphenol with the formation of the high selectivity of benzene and phenol. This goal is achieved by passing steam-hydrogen mixture through the catalyst bed Rd/Al2ABOUT3at a temperature of 80-180aboutAnd space velocities of the reaction mixture 2000-25000 h-1.All of the examples were used, the catalyst obtained by impregnation-Al2O3an aqueous solution of palladium chloride containing 0.5 wt. metal relative to the mass media, with subsequent recovery of 10% of the temperature 120-150aboutC. Before the experiments, the sample of catalyst was recovered hydrogen for 2 hours at a temperature of 300aboutC and flow rate of hydrogen 8000-10000 h-1. Upon recovery, the temperature was dropped to the reaction temperature and the catalyst was fed a mixture of a given composition.The experiments were conducted in flow-through catalytic installation in the reactor with a fluidized bed of catalyst. To prevent condensation of the initial reagents and reaction products, all communication lines and valves dispensers were heated in a heating Cabinet at a temperature of 140aboutC. analysis of the reaction mixtures was carried out by gas chromatography using detectors of ionization in flames and heat.In table. 1-3 shows the results of reductive dechlorination of dichlorbenzene and chlorinated phenols after reaching stationary activity and selectivity of catalysts. The time to reach the stationary activity of the catalysts depends on the nature of the source reagent, the reaction temperature and is 6-10 p.m. the Degree of conversion of the initial reagents, selectivity education and outputs products dehydrochlorination of dichlorbenzene are given in table. 1 is the join are not only chlorobenzene, but dichlorbenzene, mono-and dichlorphenol; high degree of conversion of chlorinated benzenes and phenols 90-100% with simultaneous high yield of benzene (up to 94%) and phenol (up to 83%); to increase the yield of the target products were used catalyst of 0.5% Pd/Al2O3obtained by impregnation of the support with an aqueous solution of palladium chloride, instead of ammonium chloride of palladium and not by an ion exchange method.P R I m e R 1. To the recovered catalyst was fed a mixture of the following composition: 1,0% para-dichlorobenzene. 10% hydrogen in an inert gas at a temperature of 80aboutC.P R I m m e R 2. The composition of the mixture as in example 1, except that the reaction temperature 100aboutC.P R I m e R 3. To the recovered catalyst was fed a mixture containing 1.0% of meta-dichlorobenzene, 10% hydrogen in an inert gas at a temperature of 80aboutC.P R I m e R 4. The composition of the mixture as in example 3 except that the reaction temperature 100aboutC.P R I m e R 5. To the recovered catalyst was fed a mixture containing 1.0% of ortho-dichlorobenzene, 10% hydrogen in an inert gas at a temperature of 80aboutC.P R I m e R 6. The composition of the mixture as in example 5, only the reaction temperature 100aboutC.P R I m e R 7. the ri temperature 80aboutC.P R I m e R 8. The composition of the mixture as in example 7, the temperature of the reaction 100aboutC.P R I m e R 9. To the recovered catalyst was fed a mixture containing 1.0% of ortho-chlorophenol, 10% hydrogen in an inert gas at a temperature of 100aboutC.P R I m e R 10. The composition of the mixture as in example 9, only the reaction temperature 150aboutC.P R I m e R 11. To the recovered catalyst was fed a mixture containing 1,0% 2,3-dichlorophenol, 10% hydrogen in an inert gas at a temperature of 130aboutC.P R I m e R 12. The composition of the mixture as in example 11, only the reaction temperature 180aboutC.P R I m e p 13. To the recovered catalyst was fed a mixture containing 1,0% 2,4-dichlorphenol, 10% hydrogen in an inert gas at a temperature of 130aboutC.P R I m e R 14. The composition of the mixture as in example 13, only the reaction temperature 180aboutC.P R I m e R 15. Temperature as in example 14, only the composition of the mixture 1,0% 2,4-dichlorphenol, 15% hydrogen in an inert gas.P R I m e R 16. Temperature as in example 14, only the composition of the mixture 1,0% 2,4-dichlorphenol, 5%hydrogen in an inert gas.This shows that the proposed method allows dechlorination is s benzene and phenol. The benzene is 82-94% phenol 34-83% when the total output deklarirovannykh products 80-100% Increase in flow rate leads to a decrease in the degree of conversion of the initial reactant and the yield of the target products, the growth of output of products of incomplete dechlorination of chlorobenzene and ortho-chlorophenol. The increase in the concentration of hydrogen in the mixture leads to an increase in product yield deeper hydrogenation of phenol cyclohexanone (example 15). The reduction of hydrogen content in the mixture increases the selectivity and product yield incomplete dechlorination of ortho-chlorophenol (example 16). The optimal molar ratio chloroaromatic compounds and hydrogen is 1:10. The METHOD shown in Fig CHLOROAROMATICS COMPOUNDS in the vapor phase fluidized bed of catalyst containing 0.5 wt. palladium on aluminum oxide, in the presence of hydrogen diluted with an inert gas, characterized in that, to increase the yield of the reaction products, as chloroaromatics connections use mono - or dichloropropane benzene or phenol, and the process is conducted at 80 180oWith a molar ratio of chloroaromatics connection; hydrogen 1 10, the content of hydrogen in inert gas about 10. with about the
FIELD: organic chemistry, chemical technology, catalysts.
SUBSTANCE: invention relates to a method for preparing acetic acid by gas-phase oxidation of ethane and/or ethylene with oxygen using catalyst comprising molybdenum and palladium. For realization of method gaseous feeding comprising ethane, ethylene or their mixture and oxygen also are contacted at enhanced temperature with catalyst that comprises elements Mo, Pd, X and Y in combination with oxygen of the formula (I): MoaPdbXcYd wherein X and Y have the following values: X means V and one or some elements optionally taken among the following group: Ta, Te and W; Y means Nb, Ca and Sb and one or some elements optionally taken among the following group: Bi, Cu, Ag, Au, Li, K, Rb, Cs, Mg, Sr, Ba, Zr and Hf; indices a, b, c and d mean gram-atom ratios of corresponding elements wherein a = 1; b = 0.0001-0.01; c = 0.4-1, and d = 0.005-1. Niobium is added to the catalyst structure using niobium ammonium salt. Preferably, niobium ammonium salt is used as the niobium source. The continuance of contact time and composite values of the parent gaseous mixture are so that taken to provide output value by acetic acid to be above 470 kg/(m3 x h). The selectivity of oxidation reaction of ethane and/or ethylene to acetic acid is above 70 mole %. Invention provides enhancing stability and output of catalyst.
EFFECT: improved preparing method.
14 cl, 1 tbl, 6 ex
FIELD: petrochemical synthesis catalysts.
SUBSTANCE: invention discloses a method for preparation of palladium catalyst comprising impregnation of alumina carrier with palladium chloride solution in presence of aqueous hydrochloric acid, treatment with reducing agent (hydrogen), washing with water, and drying, said carrier being preliminarily decoked exhausted catalyst containing alumina and group I and/or II, and/or VI, and/or VIII metals and subjected to washing with aqueous hydrochloric or nitric acid and then with water. Exhausted ethylene oxide production catalyst or methylphenylcarbinol dehydration catalysts can also be suitably used.
EFFECT: increased selectivity and activity of catalyst.
2 cl, 2 tbl, 21 ex
FIELD: supported catalysts.
SUBSTANCE: invention claims a method for preparation of catalyst using precious or group VIII metal, which comprises treatment of carrier and impregnation thereof with salt of indicated metal performed at working pressure and temperature over a period of time equal to or longer than time corresponding most loss of catalyst metal. According to invention, treated carrier is first washed with steam condensate to entirely remove ions or particles of substances constituted reaction mixture, whereupon carrier is dried at 110-130oC to residual moisture no higher than 1%.
EFFECT: achieved additional chemical activation of catalyst, reduced loss of precious metal from surface of carrier, and considerably increased lifetime.
5 cl, 9 ex
FIELD: petrochemical process catalysts.
SUBSTANCE: preparation of catalyst comprises applying palladium compound onto silica cloth and heat treatment. Palladium compound is applied by circulation of toluene or aqueous palladium acetate solution through fixed carrier bed until palladium content achieved 0.01 to 0.5%. Palladium is introduced into cloth in dozed mode at velocity preferably between 0.1 and 5.9 mg Pd/h per 1 g catalyst. Heat treatment includes drying at temperature not higher than 150oC under nitrogen or in air and calcination in air or nitrogen-hydrogen mixture flow at temperature not higher than 450oC. Original silica cloth can be modified with 0.6 to 6.5% alumina. Palladium is uniformly distributed in silica cloth and has particle size preferably no larger than 15 Å. Invention can be used in treatment of industrial gas emissions and automobile exhaust to remove hydrocarbons.
EFFECT: deepened oxidation of hydrocarbons.
5 cl, 1 tbl, 4 ex
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: palladium-containing hydrogenation catalyst, which can be used to control rate of autocatalytic hydrogenation reactions, is prepared by hydrogen-mediated reduction of bivalent palladium from starting compound into zero-valence palladium and precipitation of reduced zero-valence palladium on carbon material, wherein said starting material is tetraaqua-palladium(II) perchlorate and said carbon material is nano-cluster carbon black. Reduction of palladium from starting compound and precipitation of zero-valence palladium on carbon material are accomplished by separate portions.
EFFECT: increased catalytic activity, enabled catalyst preparation under milder conditions, and reduced preparation cost.
1 dwg, 1 tbl, 12 ex
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: preparation of catalyst comprises depositing active components on γ-alumina carrier at stirring, carrier being preliminarily treated with concentrated NaOH solution. Active components are deposited consecutively in three steps. In the first step, preliminarily prepared chitosan in acetic acid solution with KCl solution is deposited for 60-65 min; in the second step, sodium tetrachloropaladate(II) trihydrate Na2PdCl4·3H2O solution is deposited for 60-65 min; and, in the third step, hydrazine hydrate solution as reducing agent is added for 180-240 min. After each step, resulting suspension is filtered off, washed, and dried at 293-303K for 1-2 h in vacuum. Catalyst can be used in chemical industry and in processing of industrial and household wastes.
EFFECT: enhanced nitrate hydrogenation efficiency.
6 cl, 1 dwg, 6 ex
FIELD: textile, paper and chemical industries; protection of environment in production of bleachers, biocides and components of oxidizing processes.
SUBSTANCE: proposed catalyst contains one or more metals of platinum group used as active component, one or more polyolefines and activated carbon carrier. It is preferably, that polyolefines have molecular mass above 400 and are selected from ethylene homopolymers and ethylene copolymers with alpha-olefines, propylene homopolymers and propylene copolymers with alpha olefines, butadiene homopolymers and copolymers with styrene and other olefines, isoprene homopolymers and copolymers with other olefines, ethylene-propylene copolymers, ethylene-propylene diolefine three-component copolymers, thermoplastic elastomers obtained from butadiene and/or isoprene and styrene block-copolymers, both hydrogenized and non-hydrogenized. Hydrogen peroxide is produced in presence of said catalyst from hydrogen and oxygen in reaction solvent containing halogenated and/or acid promoter. Proposed catalyst makes it possible to increase degree of conversion and selectivity of process, to obtain aqueous H2O2 solutions at content of acids and/or salts at level of trace amount.
EFFECT: enhanced efficiency.
48 cl, 1 tbl,18 ex
FIELD: industrial organic synthesis and catalysts.
SUBSTANCE: invention relates to a methyl ethyl ketone production process via catalytic oxidation of n-butenes with oxygen and/or oxygen-containing gas. Catalyst is based on (i) palladium stabilized with complexing ligand and (ii) heteropolyacid and/or its acid salts, in particular molybdo-vanado-phosphoric heteropolyacid having following composition: H11P4Mo18V7O87 and/or acid salt Na1.2H9.3Mo18V7O87, said complexing ligand being notably phthalocyanine ligand. Catalyst is regenerated by making it interact with oxygen and/or oxygen-containing gas at 140-190°C and oxygen pressure 1 to 10 excessive atmospheres. Oxidation of n-butenes is conducted continuously in two-stage mode at 15 to 90°C in presence of above-defined catalyst.
EFFECT: enhanced process efficiency due to increased stability of catalyst resulting in considerably increased productivity and selectivity.
7 cl, 1 dwg, 3 tbl, 8 ex
FIELD: organic synthesis catalysts.
SUBSTANCE: catalyst for modifying colophony contains, as carrier, high-porosity cellular α-alumina-based block material and, as active catalyst fraction, sulfated group IV metal oxide and metallic palladium.
EFFECT: increased modification rate due to developed catalyst surface and eliminated disintegration and carry-over of catalyst.
FIELD: reduction-oxidation catalysts.
SUBSTANCE: invention relates to catalytic chemistry and, in particular, to preparation of deep-oxidation supported palladium catalysts, suitable, for example, in afterburning of motor car exhaust. Preparation involves depositing palladium from aqueous solution of palladium precursors followed by drying and calcination. Precursors are selected from nitrite anionic or cationic palladium complexes [Pd(NO2 -)(H2O)3]Anx or [Pd(NO2 -)n(H2O)m](Kat)y, wherein An are anions of acids containing no chloride ions, Kat is proton or alkali metal cation, n=3-4, m=0-1, x=1-2, and y=1-2. Nitrite ions are introduced into impregnating solution in the form of nitrous acid salts or are created in situ by reducing nitrate ions or passing air containing nitrogen oxides through impregnating solution. Ratio [Pd]/[NO2 -] in impregnating solution is selected within a range 1:1 to 1:4.
EFFECT: eliminated chlorine-containing emissions, increased stability of chlorine-free impregnating solutions, reduced their acidity and corrosiveness, and increased catalytic activity in deep oxidation reactions.
2 cl, 1 tbl, 16 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to chemistry of adamantanes, namely to a method for synthesis of 1-aryl-4-oxoadamantanes of the general formula: wherein R means -CH3, -OH, -N(CH3)2, -OCH3. Method involves interaction of 1-bromo-4-oxoadamantane with benzene derivative chosen from the following order: toluene, phenol, dimethylaniline or anisole in the mole ratio of reagents = 1:(506), at temperature 100-180°C in the presence Lewis acids AlCl3, FeBr3, ZnCl2 for 5-8 h. Method provides synthesis of novel compounds that are semifinished substances in synthesis of biologically active compounds.
EFFECT: improved method of synthesis.
SUBSTANCE: method of obtaining pentafluorophenol can be used for obtaining medications, fluoridated monomers and reagents for peptide synthesis by reaction of hexafluorobenzol with water solutions of alkali and earth alkali metal hydroxides. Process is carried out in presence of catalyst of interphase transfer at temperature 100-140°C. As a rule, as catalysts of interphase transfer, chlorides or bromides of tetrakis(dialkylamido)phosphonium, or N,N',N" - hexa-alkyl-substituted guanidinium, or their mixtures are used, and catalyst of interphase transfer is used in concentration from 0.5 to 1 wt % of initial hexafluorobenzol amount. Usually 2.05-2.35 equivalent of alkali reagent with respect to hexafluorobenzol is used in form of 20-30% water solution.
EFFECT: obtaining pentafluorophenol with high purity degree and simplification of its synthesis technology.
4 cl, 5 ex