The method of preparation of the palladium catalyst for the synthesis of ethyl ester of 10-(2,3,4-trimetoksi-6-were) decanoas acid
(57) Abstract:The invention relates to methods of activation unprocessed catalysts used in the synthesis of intermediates of medicines and vitamins. The method of preparation of palladium catalyst on a carbon carrier "Sibunit" hold the influence of ultrasound with an intensity of 0.1 - 3 W/cm2within 5-60 using a conical nozzle ultrasonic transducer that is dipped in a chemical glass with a catalyst, in isopropanole solution of sulfuric acid. 1 table, 3 Il. The invention relates to methods of activation of the catalysts used in the synthesis of semiconductors medicines and vitamins.It is known that activation of the catalysts most often carried out by thermal methods, which often leads to disruption of the crystal structure or physical destruction of the catalyst. Known activation method "fresh" catalyst and recovery of fatigued catalysts by treatment of aqueous culture containing bacteria, such as bacteria, reducing sulfates, oxidizing the sulfides of oxidizing iron. Catalyst p is lyst to the carrier, and activating the catalyst by bacteria, located together with the active phase of the catalyst in dilute impregnating solution. After removal of the culture, if necessary, the catalyst is heated to temperatures of 400 - 500oC (Ed.St. USSR N 190288, class B 01 J 37/34).The disadvantages of this method is that, firstly, it does not completely from the heat treatment in the preparation of the catalyst, secondly, requires for its implementation the combination of microbiological and chemical stages, which leads to the complexity of hardware implementation.The closest in technical essence is the case of the processing of platinum (Pt) and palladium (Pd) mobiles for subsequent hydrogenation of alkenes, oxidation of ethanol. Pt mobile produced in the presence of ultrasound showed an increase in surface area and magnetic sensitivity. The most active Pt mobile obtained by the treatment frequency 3 MHz, T. J. Mason - London and N.-Y. 1990, p.50).The disadvantage of this method is that the ultrasonic treatment is not having the carrier catalyst. This allows you to apply powerful ultrasound (more than 1 W/cm2), which leads to grinding of the catalyst and partially due to this increased involvement. Use is not possible, because it leads to his destruction.Task to be solved using the present invention is improving the quality of the fresh catalyst.The technical result of the invention improve the performance of the catalyst, expressed in the increase of its activity in the process of obtaining the ethyl ester of 10-(2,3,5-trimetoksi-6-were)decanoas acid.The technical result is achieved in that in the method of preparation of palladium catalyst on a carbon carrier for synthesis of ethyl ester of 10-(2,3,4-trimetoksi-6-were)decanoas acid, including the effects of ultrasound with a frequency of 22 kHz, using ultrasound with intensity of exposure of 0.1 - 3 W/cm2within 5-60 with the catalyst placed in the solution. As the catalyst used, the palladium catalyst deposited on Sibunit. This palladium catalyst powder (with particle size from 15 to 70 μm), it has a dark grey color. For the ultrasound treatment uses ultrasonic disperser of USDN A. Ultrasonic effect on the planned process for the hydrogenation of ethyl ester 9-(2,3,4 - trimetoksi-6-methylbenzoyl)nonane is 0, moreover, the entire process is carried out using a conical nozzle ultrasonic piezoelectric transducer, and the catalyst is a chemical Cup in isopropanole solution of sulfuric acid (3.8 mol/m3). When the frequency deviation in the lower side is the exit from the zone of ultrasonic vibrations, and when the deviation in a big way in terms of frequency, as well as the deviation in the lower side-intensity ultrasound exposure, it is not possible to achieve the effect of activation. When the deviation of the intensity ultrasound in a big way is the destruction of the catalyst and a significant reduction in its activity. The use of cylindrical nozzles ultrasonic transducer leads to a change in the structure of the acoustic field. In the modified acoustic field is also available for the preparation of the catalyst, but the use of a cylindrical nozzle leads to a significant loss of catalyst during its transfer from the nozzle to the reactor that is unprofitable due to the high cost of palladium. In addition, a further increase of time of ultrasonic treatment makes it impossible to conduct effective activation, resulting in low given the speed of time.Preparing to activate the raw palladium catalyst deposited on a carbon carrier Sibunit process for the hydrogenation of ethyl ester 9-(2,3,4-trimetoksi-6-methylbenzoyl)nonanalog acid to ethyl ester 10-(2,3,4-trimetoksi-6-were)decanoas acid using ultrasound exposure with an intensity of 0.1-3 W/cm2and processing time 5-60 with in isopropanole solution of sulfuric acid (3.8 mol/m3with the use of conical nozzles ultrasonic transducer is new compared to the prototype.Under the influence of ultrasonic vibrations is more evenly distribution of palladium on the surface, which apparently contributes to the formation of a larger number of active sites. In addition, according to XPS-spektroskopie ultrasonic effect on the catalyst leads to the accumulation of Pd(II), which also increases the activity.To explain the method of preparation of the raw catalyst Pd/Sibunit using ultrasonic treatment following drawings, where Fig.1 shows an ultrasound unit (General view), Fig.2 shows the change in the particle size distribution of the catalyst after ultrasonic who 2 and processing time 5 60 does not significantly change the particle size distribution of the catalyst, and hence to its destruction. In Fig.3 shows the dependence of the yield of the reaction product of hydrogenation from changes in the intensity ultrazvukova impact.The best option of carrying out the invention
For the process of hydrogenation of ethyl ester 9-(2,3,4-trimetoksi-6-methylbenzoyl)nonanalog acid to ethyl ester 10-(2,3,4-trimetoksi-6-were)decanoas acid using a palladium catalyst (dark gray) deposited on a carbon carrier Sibunit. The preparation of the catalyst to increase its activity is carried out in an ultrasonic field.Ultrasound unit consists of an ultrasonic generator 1 (USDN A) connected to the cable 2 with the ultrasonic emitter 3. Ultrasound emitter 3 sets conical nozzle 4, which is dipped in a chemical glass 5 with a catalyst, in isopropanole solution of sulfuric acid (3.8 mol/m3).Processing is performed as follows: adjusted ultrasonic generator 1 by time and intensity ultrasound exposure, novelty.The results of the regeneration of the catalyst are given in table. 1 and in Fig. 3.The proposed method of regeneration is implemented on the industrial output of the ultrasonic generator, the process is fast and gives good results. The method of preparation of the palladium catalyst for the synthesis of ethyl ester of 10-(2,3,4-trimetoksi-6-were)decanoas acid, including the effects on the catalyst ultrasound with a frequency of 20 to 22 kHz, characterized in that as a palladium catalyst using a catalyst containing palladium on a carbon carrier Sibunit and influence carry out the ultrasound with intensity ultrasound exposure 0,1 3 W/cm2for 5
60 in isopropanole solution of sulfuric acid.
R1-- CCHR1-- CHCH2< / BR>R1, R2H, alkyl,C CHCH2CH2; R1,R2-alkylene, for example (CH2)5
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