SU1109190A1 - Process for producing catalyst for hydrogenizing organic compounds - Google Patents

Abstract

A METHOD FOR OBTAINING A CATALYST FOR HYDROGENING ORGANIC COMPOUNDS by saturating the nickel lanthanide intermetallide with hydrogen: at elevated temperature and pressure to form a hydride phase, characterized in that with -. In order to obtain a catalyst with increased activity, the intermetallic reaction with hydrogen is carried out in the presence of water vapor at 150-350 ° C. (L with

Description

, 1 The invention relates to the chemical industry, in particular to methods for the preparation of catalysts for the hydrogenation of organic compounds. A known method for the preparation of catalysts for the hydrogenation of organic compounds 1 on the basis of intermetallic compounds of nickel consists in the leaching of Ni-AlNi-Mg alloys with an alkali solution followed by washing with distilled water tl. However, the skeletal nickel catalysts thus obtained easily lose their activity during the hydrogenation of organic compounds, especially during the hydrogenation of aromatic nitro compounds. The closest to the invention in its technical essence and the effect achieved is a method for preparing a catalyst for hydrogenating organic compounds by hydrogenation of intermetallic compounds at elevated temperature and pressure until the formation of the hydride phase. Moreover, as intermetallic compounds, compounds of the general formula RMen are used, where R is Ra Rr, Y; Me — Fe, Co, Ni; n 2-5, a hydrogen saturation is carried out in an autoclave at 50 ° C and a pressure of 30 at. C23. However, this method produces a catalyst with insufficiently high 1 activity. For example, the reduction of nitriles at 10 atm occurs at 70-100 ° C, and the yield of hexane during the hydrogenation of hexene-1 for 30 minutes is 96%. The purpose of the invention is to obtain a catalyst with increased activity. This goal is achieved in that according to the method for preparing a catalyst for hydrogenation of organic compounds by saturating the nickel lanthanide intermetallic with hydrogen at elevated temperature and pressure until the hydride phase is formed, the intermetallic is saturated with hydrogen in the presence of water vapor at 150-350 ° C and elevated pressure to form the hydride phase. The proposed method makes it possible, in comparison with the known method, to obtain a catalyst with increased activity due to an increase in the size of the working surface and an increase in the mobility of hydrogen dissolved in the crystalline hydride lattice. The proposed catalyst is prepared as follows. Charged lanthanide nickel is loaded into the reactor, water is poured in a mass ratio to lanthanide nickel (O, 17-0.5): 1,. The reactor is washed with a current of hydrogen, the pressure of hydrogen is raised to 30 atm, and the reactor is heated to 150-350 ° C for 10 minutes. Then the heating is turned off and the reactor is cooled to 25 ° C for 30 minutes. At the same time, the intermetallic is saturated with hydrogen to form the hydride phase of the LaNigH -d j composition. Then the pressure is reduced to 20 atm, the solvent is injected into the reactor and the hydrogenation reaction is carried out. The activity of the catalyst increases with the amount of added water as long as its surface remains available for water vapor at the time of treatment, and decreases sharply if the surface of the intermetallic is covered with a film of water under the conditions of treatment (Table 1). Processing should be carried out at 150-350 ° C. At lower temperatures, the pressure of saturated water vapor is insufficient to activate the surface of the intermetallic compound. At higher temperatures, sintering of the catalyst is observed (Table 2). Example 1. Charged to the reactor 3 g of LaNij powder, pour 1.5 ml of HjO. The reactor is washed with a stream of hydrogen. Hydrogen is supplied from a cylinder to a pressure of 30 atm and the reactor is heated to 10 ° C for 10 minutes. Then the heating is turned off, the reactor is cooled to 25 ° C for 30 min and the intermetallic is saturated with hydrogen to form the hydride phase of LaNigH (j (, j). Then the pressure is reduced to 20 atm, 40 ml of 96% ethanol is poured into the reactor , 2.8 ml of hexene - 1, the reaction is completed in 4 minutes. The yield of hexane is 100%. The X-ray analysis of the proposed catalyst before and after the reaction showed that it does not differ in any way from that prepared in a known manner. Example 2. The catalyst is prepared as in Example 1 Then relieve pressure to 20 a 40 ml of water, 1.1 WI of dimethylethynylcarbinol is poured into the reactor, the reaction is completed in 5 minutes, the yield of tertiary amyl alcohol is 100%. On the same catalyst without regeneration and with the same activity, it is possible to hydrogenate the following portions of DMEK to amounts limited reactor.

Example 3. The catalyst was prepared according to Example 1. The pressure was released to 20 atm, 40 ml of water, 0.75 ml of nitrobenzene were poured into the reactor. The reaction is complete in 10 minutes. The yield of aniline is 100%. On the same catalyst, without regeneration, with the same activity, it is possible to hydrate another 10 batches of nitrobenzene, 0.75 ml each (Table 4) ..

Example 4. Into the reactor load 3 g of powder LaNij, pour 0.5 ml of HjO. The reactor is washed with a stream of hydrogen. Hydrogen is supplied from a cylinder to a pressure of 30 atm and the reactor is heated for 10 minutes to 250 ° C. Then the heating is turned off, for 30 minutes, the reactor is cooled simultaneously and the intermetallic is saturated with hydrogen to form the hydride phase.

 6

Then relieve pressure to

20 atm, 40 ml of 96% ethanol, 1.1 ml of dimethylethynylcarbinol are poured into the reactor. The reaction is completed within 15 minutes. The output of tertiary amyl alcohol 100%.

Example 5, load 3 g of LaNij powder into the reactor, pour 1.0 ml of H.jO. The reactor is washed with a stream of hydrogen. Hydrogen is supplied from a cylinder to a pressure of 30 atm and the reactor is heated for 10 minutes to 350 ° C. Then the heating is turned off, and the reactor is cooled simultaneously for 30 minutes and the intermetallic is saturated with hydrogen to form the hydride phase of composition LaKijHg. Then the pressure is released to 20 atm, 40 ml of 96% ethanol, 1.1 ml of dimethylethynyl carbinol are poured into the reactor. The reaction is completed in 11 minutes. The code of tertiary amyl alcohol is 100%.

UPMER 6. The reactor is charged with 3 g of LaNij powder, 1.5 ml of HjO are poured. The reactor is washed with a stream of hydrogen. Hydrogen is supplied from a cylinder to a pressure of 30. atm and is heated.

reactor for 10 min before. Then the heating is turned off, for 30 minutes, the reactor is simultaneously cooled to 25 ° C and the intermetallic is saturated with hydrogen to form the hydride phase of the composition

Then relieve pressure to

20 atm, 40 ml of 96% ethanol, 1.1 ml of dimethylethynylcarbinol are poured into the reactor. The reaction is complete in 8 minutes. The yield of tertiary amyl citrate 100%.

As can be seen from the table. 1, the maximum rate of hydrogenation (Wp, p) under experimental conditions (reactor volume 120 ml) is achieved when the ratio of the amount of evaporated water (ml) to the amount of LaNij. (g) equal to 1: 2.

As follows from the table. 2, the optimum for treating the LaNij intermetallic compound with water vapor (, 5.ml) is 250 ° C.

The test results of the hydrogenated compounds according to the known and proposed methods are given in table. 3

From tab. 3, it can be seen that the treatment of LaNij at the time it is filled with hydrogen by water vapor 10 times or more increases the catalytic activity of the resulting LaNijHg hydride. especially when reducing aromatic nitro compounds, which allows reducing the temperature of this reaction to 20 ° C.

In tab. 4 shows the sequential hydrogenation of several batches of a substance in one portion of the catalyst.

From tab. 4, it follows that the LaNigH g. {, 5 catalyst prepared by the proposed method exhibits high stability in the reactions of liquid-phase catalytic hydrogenation of organic compounds, including aromatic nitro compounds, which is of great practical interest. Thus, the hydrogenation of the tenth sample of nitrobenzene in one portion of the prepared catalyst proceeds even at a slightly higher rate than the first.

Compared with the known method, the proposed method allows a 6–10 fold increase in catalyst activity in the hydrogenation of acetylene compounds by a factor of 3.5 to decrease the reaction rate without reducing the catalysis activity.

torus when restoring aromatic nitro compounds, i.e. reduce energy costs, as well as reduce the consumption of catalyst. The catalyst prepared according to the proposed method exhibits high stability in the liquid-phase hydrogenation of organic compounds, including those with a high adsorption potential such as nitrobenzene, and easily deactivating existing conventional metal catalysts. Extension of Table 1

125 1.5 5.0 18

table 2

Water

96% ethanol

Hexene-1 2.8 Hexene-1 2.8

Nitrobenzene, 0.75

Water

116

20

12,125

83 280

90

Average ml Hj / min

3 3

50 o

75 20

80

Claims (1)

METHOD FOR PRODUCING A CATALYST FOR HYDROGENING ORGANIC COMPOUNDS by saturation of nickel lanthanide intermetallic compound with hydrogen at elevated temperature and pressure until the hydride phase is formed, characterized in that, in order to obtain a catalyst with increased activity, hydrogenation of the intermetallic compound is carried out in the presence of water vapor at 150 -350 ° C. > . 1109