SU1593698A1 - Method of preparing tabletted catalyst for conversion of carbon oxide - Google Patents

Abstract

The invention relates to catalytic chemistry, in particular the preparation of a preformed catalyst for the conversion of carbon monoxide. The goal is to increase the activity, strength and stability of the catalyst. The latter is prepared by mixing iron oxide with chromic anhydride, KM NO 4 and a binding additive — aluminum stearate in an amount of 0.5–1 wt.%. Then drying, tableting and calcining are carried out at 400-450 ° C. The resulting catalyst loses mechanical strength by 1% over a month against 5% in the known case without loss of activity. 2 tab.

Description

The invention relates to methods for preparing tabletted iron-chromium catalysts for the medium-temperature conversion of carbon monoxide and can be used in the chemical industry.

The purpose of the invention is to obtain a catalyst with increased activity, mechanical strength and stability by changing the binder additive and the calcination temperature.

Example 1. To prepare .200 g of an iron-chromium catalyst, take 21 g of chromic anhydride, dissolve in 20 ml of water, and then mix thoroughly with 184 g of iron oxide. 60 ml of water are added and again mixed thoroughly for 30 minutes at room temperature. The resulting mass is conducted in air, dried at 100-105 ° C to a constant BecJa, then cooled to room temperature and triturated.

Take 20 g of the prepared catalyst mass and mix with 0.15 g of aluminum stearate (0.75 wt.%). Then the catalyst is tableted. The prepared sample is heated step by step first to 100 ° C with a speed of 30-50 degrees / hour, kept at this temperature for about 2 hours, then heated to 130 ° C. At a temperature of 110 ° C, the catalyst is self-heating with a heat effect of 60 cal / g. The catalyst is maintained at a temperature of less than 200 ° C for 2-3 hours. Then the catalyst is heated to 400-450 ° C and calcined for 3-4 hours. Self-heating of the catalyst during calcination is not observed.

The chemical composition and physico-chemical properties of the proposed and known catalysts are given in table. one.

PRI mme R 2. A zhepezokhromovy catalyst prepared with the addition of potassium manganese-acid. To do this, 184 g of iron oxide are thoroughly mixed with 5.52 g of dry KMPO.

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with y

00

and ground in a dry form. 60 ml of water are added, mixed again and triturated.

21 g of chromic anhydride are dissolved in 20 ml of water and added to the previously obtained mass, thoroughly mixed for 30 minutes. They are allowed to air, dried at 100-105 ° C to a constant weight. The dried catalyst is ground. Take 20 g of the prepared catalyst mass and mix with 0.2 g of aluminum stearate (1 wt.%). Next, the catalyst is tableted. The sample is heated in steps, dried and calcined in example 1.

Example 3 (comparative). 0.3 g of aluminum stearate (1.5 wt.%) Was added to 20 g of the prepared catalyst mass, and the aluminum stearate was thoroughly mixed with the catalyst. The resulting catalyst is tableted. Next, the catalyst is heated, dried and calcined in example 1.

Example 4. Take 184 g of ReaOz and mix with 19 g of manganese-acid potassium, mix thoroughly and triturate in a dry form.

60 ml of water are added and again mixed and triturated. 21 g of Cr3O3 are dissolved in 20 ml of water and added to the resulting mass, mixed thoroughly for 30 minutes. They are allowed to air, dried at 100-105 ° C to a constant weight. The dried catalyst is ground.

Take 20 g of the prepared catalyst and mix with 0.15 g of aluminum stearate (0.75 wt.%). Next, the catalyst is tableted. Stabilized catalyst is heated, dried and calcined in example 1.

Example 5. To 20 g of the prepared catalyst mass was added 0.2 g of aluminum stearate (1 wt.%). Next, the catalyst tableted, heated, dried and calcined according to example 1.

Example 6. To 20 g of the prepared catalyst mass was added 0.1 g of aluminum stearate (0.5% by weight). Next, the catalyst tableted, heated, dried and calcined according to example 1,

Example 7 (comparative). To 20 g of the prepared catalyst mass was added 0.06 g of aluminum stearate (0.3 wt.%). Next, the catalyst tableted, heated, dried and calcined according to example 1.

Example 8. To 20 g of the prepared catalyst mass was added 0.4 g of aluminum stearate (2% by weight). Next, the catalyst is tableted, heated, dried and calcined according to example 1.

Example 9. To 20 g of the prepared catalyst mass is added 0.6 g of aluminum stearate (3 wt;% Next, the catalyst is tableted. Heated and

calcined in example 1.

Example 10. To 20 g of the obtained catalyst mass was added 1.4 g of aluminum stearate (7% by weight). Next, the catalyst is tableted, heated, dried and

0 calcined in example 1.

A comparative characteristic of the known and proposed catalysts is given in Table 1. As can be seen from the table, the application of the invention makes it possible to reduce the value of the thermal exoeffect and transfer the effect to a zone of lower temperatures. The result is a catalyst for the conversion of carbon monoxide, which has a higher activity,

0 mechanical strength and stability.

compared to the known catalyst.

The activity of the catalysts is determined by

on a flow-circulation installation in

kinetic mode at a volumetric rate of 12,000 hours at a temperature of 350 ° C, on a gas of the following composition,%: CO 12.5; N2 12.5; H20 75. Activity is estimated by the rate constant for the 1st order equation for carbon monoxide.

0B table. 2 shows comparative

data on the stability of the catalyst prepared by the well-known and proposed methods when tested for 1 month of continuous operation at 350–380 ° C, a volume rate of 5000 hours, the CO content at the inlet is 12 vol.%, a steam: gas ratio of 0.6; 1. The proposed method produces a more stable catalyst compared to the known one. The proposed catalyst works for 1 month without loss of activity (the activity of the catalyst according to the well-known Method is reduced by 14%) and is characterized by a smaller loss of mechanical strength (by 1%) as compared with the known (by

5 5%).

Claims (1)

Claim Method for Preparing a Tableted Catalyst for the Conversion of Carbon Monoxide by Mixing an Iron Compound 0 with chromic anhydride, manganese-acid potassium and a binder additive, followed by drying, tableting and calcining, in order to obtain a catalyst with enhanced activity, mechanical strength and stability, iron oxide is used as an iron compound, and, as a binding additive, aluminum stearate in the amount of 0.5-1 wt.% and calcination is carried out at 400-450 C. J (XI is ill  about so 04 CO in Yu CM t O) 00 OO 00 o SC CO CO s in § CO OO MF to 00 w en r in o OO O)  to ABOUT) about. with: about (0 ° at 0) 3 O) X " about t Is ABOUT) with I about “About 5 | iU. X FS —e s; X th S oSii §Oso "J with " & SS §2 OK 51 CS From 2 SG about ABOUT & e i S g .1 11 with; about with  ° to about. S S with Z About About About g- 1 about about about Yu oh oh ON CO yoo o T-C4 her Q - Q (Oh (Oh cx 1 1 oh oh oh Yu O) Yu O (Oh (Oh oo gy oo s a u) g . io " 1 21 ilsfg about a: S J. 2 liBl table 2