SU1727872A1 - Catalyst for hydrating ethylene - Google Patents

Abstract

The invention relates to the chemistry of catalysis, in particular to the use of high-silica zeolite of the pentasil type in the ammonium-hydrogen form with the content of ammonium ions in an amount of 0.3-0.8 wt,% based on nitrogen as a catalyst for the hydration of ethylene. The use of this pentasil allows increasing the duration of the catalyst operation without regeneration up to 200 hours; in addition, the catalyst retains its activity in the ethylene hydration reaction over a wider range of temperatures (280-320 ° C) and ratios of reactants (molar ratio water-ethylene) 0.75-1.5: 1). 2 tab. cl

Description

The invention relates to the chemistry of catalysis, in particular, for the preparation of ethyl alcohol by hydration of ethylene.

The purpose of the invention is to increase the duration of the catalyst and increase its stability, i.e. maintaining ethylene hydration in a wider range of operating temperatures and reagent ratios by using high-silica zeolite of the pentasil type in ammonium form as a catalyst, which is known as an intermediate in the preparation of the hydrogen form of this zeolite.

Example 1 (comparative). 5 cm3 of catalyst (hydrogen form of zeolite ZSM-5) is loaded into a flow-through steel reactor equipped with an evaporator. Ethylene (10 l / h) and water (12 ml / h) are passed through the catalyst. The ethylene-water ratio is 1: 1.5 (mol%). The ethylene feed rate given is 2000. Pressure 4.5 MPa. The temperature during the reaction is gradually increased from 280 to 300 ° C. After separation of the catalyzate from the unreacted gas, a water-alcohol solution was obtained with an ethanol concentration of 8.9% by weight, ethylene conversion per pass of 4.6%, ethanol productivity 402 g / kg. h. The duration of the catalyst before regeneration 35 hours

An increase in the temperature of the process to 310 ° C or a decrease in the water supply to 10 ml / h leads to an instant deactivation of the catalyst, heating it to over 700 ° C and the appearance of catalytic VI VI VI with vi

hydrocarbons in water. After regeneration, the catalyst activity is reduced by no more than 30–40% (ethylene conversion per pass is 1.5 mol.%).

Example 2. 500 g of the hydrogen form of a high-silica-type zeolite ZSM-5 in the form of granules with a diameter of 3 mm is subjected to saturation with gaseous ammonia at 10-30 ° C or treated with 25% ammonia at 95-100 ° C for 1 hour. In the latter if the catalyst is filtered off. In both cases, the catalyst was dried for 2 hours at 150 ° C to remove moisture and physically sorbed ammonia. Get the ammonium form of the zeolite ZSM-5 with an ammonia content of 1.1 wt.% (In terms of nitrogen). Partial removal of chemisorbed ammonia is achieved by calcining at 300-500 ° C for 5 hours.

The results of testing samples of the catalyst obtained by the described method in the reaction of hydration of ethylene are given in examples 3-8. Ethylene hydration was performed as described in Example 1.

The test results of the catalyst samples are presented in table 1.

When ethylene is hydrated using this catalyst, an increase in the temperature of the reaction to 320 ° С or a decrease in the water supply to 6 ml / h during the reaction does not lead to a decrease in productivity and a decrease in the duration of the catalyst without regeneration.

Regeneration of the catalyst, which involves calcining it in a stream of air at a temperature of 500-540 ° C for 5 hours and then treatment with ammonia, as described in Example 2, completely restores the activity of the catalyst.

The test results of the regenerated catalyst samples are presented. in table.2.

Examples 9 and 10. Catalyst on

on the basis of pentasil in sodium form is subjected to ion exchange with ammonium nitrate, dried and calcined in air at 300-500 ° C. Depending on the calcination temperature, a hydrogen-ammonium form is obtained with a different residual content of ammonium ions.

Ethylene was hydrated on the obtained catalyst as in Example 1. A short-term increase in the course of the reaction temperature to 320 ° C and a decrease in the supply of water to 0.8 mol per mole of ethylene did not lead to uncontrolled heating of the catalyst and its deactivation.

As can be seen from the above data, modification of the catalyst for the hydration of ethylene based on high-silica zeolite with ammonium ions, according to the invention, makes it possible to increase the duration of the catalyst without

regeneration up to 200 hours with a slight decrease in the average hourly performance. In addition, the catalyst retains its activity in the ethylene hydration reaction over a wider range of temperatures (280-320 ° C) and reagent ratios (molar ratio water: ethylene 0.75-1.5: 1).

Formulations of the Invention The use of high silicon zeolite of the pentasil type in hydrogen-ammonium form with the content of ammonium ions in an amount of 0.3-0.8 wt.% In terms of nitrogen as a catalyst for ethylene hydration.

Table

table 2

Claims (1)

Claim 35 The use of high-silicon zeolite of the pentasil type in the hydrogen-ammonium form with a content of ammonium ions in an amount of 0.3-0.8 wt.% In terms of nitrogen as a catalyst for hydration of ethylene 40. Table 1 Example Ammonium ion content, May. % (in terms of nitrogen) Conversion of ethylene per passage, pier. % Ethanol Concentration in Catalysis, May. % Productivity, g / kg · h Duration of run, h We eat ethanol per run, kg / kg 1 4.6 8.9 402 35 14.07 3 0.3 4.5 8.0 396 150 59.4 4 0.63 4.2 7.5 370 200 74.0 5 0.8 2.9 5.0 244 200 48.8 6 1.1 1.1 2.2 104 260 04/27 7 0.11 4.6 8.8 400 fifty 20 8 0.20 4.5 8.4 398 95 37.8 9 0.4 4.41 - 388 170 65.9 . 10 0.6 4.25 - 374 195 72.9 table 2 Example The content of ammonium ions. mys. % Conversion of ethylene to the passage, pier. % Ethanol Concentration in Catalysis, May. % The performance of the catalyst, g / kg · h Duration of run, h Ethanol removal per run, kg / kg 1 0.31 4.4 8.0 393 150 58.9. 2 0.58 4.2 7.4 360 200 72.0 3 0.77 2.9 5,0 240 196 47.0 Compiled by T. BeloslyudRva Editor N. Khimchuk Tehred M. Morgenthal Corrector S. Cherni --------, ------------------: ---------------: ------ ---: ---------------, ---------: —'- C - + --- Order 1360 Circulation Subscription VNIIIPI of the State Committee for Inventions and Discoveries under the State Committee for Science and Technology of the USSR 113035, Moscow, Zh-35, Raushskaya nab., 4/5 Production and Publishing Combine Patent, Uzhgorod, 101 Gagarin St.