Method for deoxidizing solid catalyst precursor

Abstract

The invention relates to a method for deoxidizing solid catalyst precursor, in particular to a preparation method of deoxidized load type metal catalyst. The invention provides a method for deoxidizing the solid catalyst precursor under the condition of non-calcination, which can reduce the probability of strong interaction between metal component and a carrier, migration and agglutination of metal particles that are deoxidized can be inhibited, and the obtained catalyst has higher hydrogenation activity. The method comprises: first, metal salt is fully dissolved in the water; the carrier is added into the solution to react for 5-8h; after being filtered, the obtained solid is dried at the temperature of 140-160 DEG C for 8-10h, and the catalyst precursor is obtained; after that, the prepared catalyst precursor is placed into a high temperature resistant container, reducing gas is continuously filled into the container, and reductive treatment is carried out for 5-50min at the temperature of 300-1000 DEG C; then, the container is transferred into the room temperature environment from the high temperature environment for fast cooling, and the deoxidizing process is completed. The method is applicable to deoxidizing the catalyst of catalytic hydrogenation reaction, especially the catalyst of aromatic hydrogenation reaction.

Description

technical field [0001] The invention relates to the preparation of a reduced-state supported metal catalyst. Background technique [0002] When preparing a reduced-state supported metal catalyst, the general method used is: first, the corresponding metal salt is loaded on the carrier, and then roasted at a high temperature to convert the metal salt into the corresponding metal oxide, and finally the metal oxide is reduced. . A typical reduction step is: placing the metal oxide-carrier compound in a high-temperature-resistant metal tube, then placing the metal tube in a reaction furnace, introducing a reducing gas such as hydrogen, and then slowly raising the temperature to a certain temperature such as 300 ~600°C, keep the temperature constant for several hours or even dozens of hours (Chinese patent CN1781599), and finally slowly drop to room temperature. [0003] The reduction step of the catalyst determines the morphology, size and reduction degree of the metal particle...

AI Technical Summary

Problems solved by technology

There are following shortcoming in the preparation method (J Catal 45 (1976) 41-53, Appl Catal A 106 (1993) 73-82) of common reduction state supported metal catalyst: In the process of calcination into metal oxides, the metal components often interact strongly with the support, and even form some complexes, such as NiO and Al 2 o 3 Generate Ni-Al spinel

The existence of this strong interaction phenomenon makes the reduction of metal oxides difficult

In this case, in order to enable the reduction of metal oxides, the reduction temperature must be increased, but the increase in the reduction temperature has a negative effect, even if the reduced metal particles are easy to migrate and coalesce, thus forming larger-sized particles. Particles, which reduce the surface area of ​​the particles, eventually leading to a reduction in the number of catalyst active sites

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