Preparation method for hydrotreatment catalyst

Abstract

The invention discloses a preparation method of a hydrotreatment catalyst. The preparation method comprises the following steps: preparing a carbon-containing modified alumina-based carrier; loading the carrier with hydrogenation active metal component by using an impregnation process; and carrying out drying to obtain the hydrotreatment catalyst. A preparation method for the carbon-containing modified alumina-based carrier comprises the following steps: sequentially or simultaneously introducing water-soluble silicon oil, a soluble aid and a carbon precursor into an alumina-based carrier and carrying out heat treatment so as to obtain the carbon-containing modified alumina-based carrier. The method can adjust the distribution of an acid center and a hydrogenation active center to make the acid center and the hydrogenation active center coordinate with each other, thereby improving the comprehensive performance of the hydrotreatment catalyst.

Description

technical field [0001] The present invention relates to a preparation method of a hydrotreating catalyst, in particular to a preparation method suitable for a heavy distillate hydrotreating catalyst. Background technique [0002] Most supported catalysts are prepared by impregnation, such as various hydrogenation catalysts. Alumina is often used as a support material for this type of catalyst. but pure Al 2 O 3 The interaction force between the active metal on the surface and the carrier is large, and it is easy to form inactive species (such as the formation of nickel-aluminum spinel), and it is not easy to be completely sulfurized to form a type II active phase with high hydrogenation activity. At the same time, the acidity of the catalyst surface has a great influence on the activity of the hydrogenation catalyst. The removal of heteroatoms in the raw material requires the catalyst to have hydrogenolysis activity, which occurs at the acid center of the catalyst. Theref...

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Problems solved by technology

Due to the addition of these carbon precursors, the calcination temperature of the carrier in an oxygen-containing atmosphere cannot be too high, otherwise the carbon will be oxidized and lost. Therefore, for some catalysts that require high-temperature treatment of the carrier, this method is not feasible, and too much The addition of carbon black powder will affect the strength of the catalyst, which is not conducive to large-scale application

[0008] In the above-mentioned prior art, the co-precipitation method or additives are added during molding. The former will cause active metals and Si and other additives to enter the bulk phase during the co-precipitation process, and multiple substances are precipitated at the same time. The same precipitation conditions are impossible At the same time, it is the best precipitation condition for a variety of substances; while the latter adds additives such as Si during kneading and molding, which is not conducive to the uniform dispersion of additives.

Using a well-formed alumina carrier and coating carbon on its surface is a better way to solve the problem of activated carbon as a carrier. However, the existing carbon coating method has a complicated preparation process and high cost, and is difficult to industrialize on a large scale. The acidity of the carrier is reduced, which is not conducive to the improvement of the comprehensive performance of the catalyst

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