Preparation method of hydrocracking catalyst

Abstract

The invention discloses a preparation method of a hydrocracking catalyst. The preparation method comprises the following steps: enabling a magnesium, aluminum and silicon-containing acidic solution and a tungsten-containing alkaline solution to form mixed slurry; enabling a nickel-containing acidic solution and the tungsten-containing alkaline solution to form mixed slurry; then mixing the slurries, adjusting the pH value, aging, mixing and grinding Y molecular sieves and high-molecular polyethylene glycol, adding into mixed slurry, filtering and drying; forming to prepare the hydrocracking catalyst. Through improvement in the hydrogenation activity of the catalyst and effective cooperation of acidic functions, the nitrogen resistance of the catalyst is improved, so that the catalyst still has good hydrocracking activity and better performance of delaying carbon deposition under the condition of higher nitrogen content of a reactant.

Description

technical field [0001] The invention relates to a preparation method of a hydrocracking catalyst, in particular to a preparation method of a nitrogen-resistant prolific middle distillate oil hydrocracking catalyst. Background technique [0002] In recent years, the rapid development of the world economy has driven the increasing demand for middle distillates in the transportation industry, and the extraction of crude oil has also increased, leading to further expansion of the trend of heavy and inferior crude oil. At the same time, more and more attention has been paid to the harm of pollutants emitted by fuel combustion to the environment on which human beings depend, and stricter environmental protection regulations have also been introduced. As a result, refineries are faced with many arduous tasks such as increasing difficulty in raw material processing, product quality upgrades, and continued strong market demand for middle distillates. [0003] Hydrocracking can conve...

AI Technical Summary

Problems solved by technology

These several preparation methods have their own advantages and disadvantages. The kneading method of active metals and acidic components, carriers, additives, etc. is kneaded together. Due to the limitation of the preparation method, it is impossible to achieve a very uniform dispersion of each active component, which will make the catalyst partially metal or The aggregation of acidic components affects the effective performance of its activity, or the local reaction of the catalyst strongly leads to the coking and deactivation of the catalyst

The impregnation method carrier is generally prepared by kneading method, and the silica-alumina and molecular sieves cannot be uniformly dispersed during the kneading process. The metal is introduced by the impregnation method, and the capillary force between the particles will cause the active components to agglomerate during the drying and roasting process. , forming larger particles, reducing the dispersion of active metals

The co-precipitation method can make the metal and the carrier and the acidic component disperse very uniformly, and form a weak interaction between the active metal and the carrier, but the distribution of the active metal on the catalyst from the inside to the outside is basically uniform. When the catalyst is in contact, some metals that cannot be reached by the reactants will become ineffective components, thereby reducing the utilization rate of active metals; co-precipitation preparation of hydrocracking catalyst molecular sieves is generally dispersed in the precipitation slurry, if not protected, part of the pores It will also be blocked by precipitated particles, so that some functions of the molecular sieve cannot be fully exerted

[0011] CN101172260A discloses a method for preparing a hydrogenation catalyst. The carrier material is amorphous silica-alumina, and molecular sieves are introduced during the gelation process; in the method for preparing a hydrocracking catalyst disclosed in CN101239324A, Y molecular sieves are directly added to the co-precipitation mixture Introduced into the catalyst, the above method can block some pores and affect the efficient performance of its acidic function

[0012] CN1253988A discloses a nitrogen-resistant type prolific middle distillate hydrocracking catalyst, and CN1253989A discloses a heavy hydrocarbon hydrocracking catalyst and its preparation method. The preparation methods of these two catalysts all use active metal and carrier In the co-precipitation method, although the active metal, the carrier and the acidic component can be uniformly dispersed, the co-precipitation of the active metal and the carrier auxiliary agent will cause mutual wrapping, so that some metal components cannot be fully exposed in the bulk phase and become invalid components. points, each active component of the prepared catalyst cannot play a role efficiently

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