A kind of preparation method of hydrodearomatization catalyst

Abstract

The invention discloses a preparation method of a hydro-dearomatization catalyst. According to the method, an NaY type molecular sieve raw material with relatively high silica-to-alumina ratio, high crystallinity and good stability is adopted; through the sequential steps of ammonium exchange, hydrothermal treatment, dealumination and silicon substitution, and acid and ammonium salt mixed solution treatment, a small-grain Y type molecular sieve is obtained; the small-grain Y type molecular sieve is adopted as an acidic component, and is complexed with amorphous silica-alumina, an active component and an auxiliary component, such that higher hydro-dearomatization activity is provided. The catalyst is especially suitable for hydro-dearomatization and decoloration processes of cycloalkyl high-viscosity white oil and solvent oil comprising heavy aromatics.

Description

technical field [0001] The invention relates to a preparation method of a hydrogenation refining catalyst, in particular to a preparation method of a hydrogenation dearomatization catalyst. The catalyst is suitable for the hydrogenation process of aromatics, especially for the hydrogenation and dearomatization process of naphthenic oil containing heavy aromatics. Background technique [0002] Under aerobic conditions, the oil produced by hydroprocessing (such as high-grade lubricating oil, food-grade white oil, etc.) is very sensitive to sunlight and ultraviolet radiation. Exposure to sunlight and air will cause the appearance and performance of the oil to be unstable, and the color of the oil will deepen , in severe cases, precipitation occurs. This type of oil requires low viscosity, high flash point and boiling point, and low volatility. Colorless, odorless, low aromatics content, non-corrosive, good thermal stability and oxidation stability, not easy to cause gelation,...

AI Technical Summary

Problems solved by technology

In this method, the raw material needs to be treated with ammonium hexafluorosilicate for dealumination of silicon, and then undergo hydrothermal treatment and other treatments, so as to reduce the collapse of the molecular sieve skeleton structure and improve the crystallization retention of the molecular sieve. After treatment with ammonium hexafluorosilicate for dealumination and silicon supplementation, due to the isomorphic substitution of silicon and aluminum, the molecular sieve silicon oxide aluminum structure is relatively complete, and then hydrothermal treatment will form less secondary pores, and the proportion of secondary pores is low. Facilitate the diffusion of reaction products, low saturation of aromatics

[0007] At present, due to the poor hydrothermal stability and unstable structure of small-grain NaY molecular sieves, small-grain Y-type molecular sieves with complete structure, high crystallinity and many secondary pores cannot be obtained after subsequent modification.

[0008] In the preparation process of the existing method, small-grain NaY molecular sieves, silicon and aluminum are easily lost, the utilization rate of silicon is low, and the distribution of silicon and aluminum is not uniform, and it is easy to appear agglomeration, so the existing methods still cannot prepare small-grain NaY molecular sieves with high silicon-aluminum ratio and good thermal stability and hydrothermal stability