Improved diesel hydrocracking catalyst carrier and preparation method thereof

Abstract

An improved diesel hydrocracking catalyst carrier and a method for preparing same. Raw materials of the carrier comprise the following components in percentage by weight: 3-35% of molecular sieve, 5-75% of γ-Al2O3, 15-75% of amorphous silica-alumina, and 7-40% of binder. The specific surface area of the carrier is 200-450 m2 / g, and the total pore volume is 0.35-0.75 cm3 / g. During preparation of a composite of molecular sieve and alumina, a molecular sieve without removing a templating agent is added; in a mixed liquid, NH4+ which is generated by means of reaction of an aluminum salt and ammonia water and alkali Na+ which balances negative charges of a molecular sieve framework are exchanged; during roasting, an organic templating agent and NH4+ in the molecular sieve are removed, so that ammonium exchange and templating agent removal of a zeolite molecular sieve are completed during preparation of the composite, without separately performing templating agent removal and ammonium exchange on the molecular sieve. The templating agent has supporting and protecting effects on the pore structure of the molecular sieve. A hydrocracking catalyst prepared using the carrier can remarkably reduce the pour point of a diesel fraction and improve the cetane number of diesel while guaranteeing a high diesel yield.

Description

technical field [0001] The invention relates to a catalyst carrier, in particular to an improved diesel hydrocracking catalyst carrier and a preparation method thereof. Background technique [0002] With the rapid development of the economy, the demand for petroleum products has grown rapidly, and my country's hydrocracking processing capacity has also achieved rapid development. However, as the quality of raw oil processed in my country gradually becomes heavier and worse, the processing volume of high-sulfur crude oil is increasing year by year, and environmental protection has increasingly strict requirements on the refining process itself and the quality of petroleum products, which put forward higher requirements on the level of hydrocracking technology , while the catalyst plays a central role in the hydrocracking reaction, the key to the hydrocracking technology lies in the development and improvement of the catalyst. [0003] The conventional preparation methods of h...

AI Technical Summary

Problems solved by technology

CN1393521A discloses a medium-oil type hydrocracking catalyst and its preparation method. The carrier used in the catalyst is amorphous silica-alumina, composite molecular sieve of alumina, Y and β molecular sieve, wherein the composite molecular sieve is to burn off the former powder of β molecular sieve to remove template After mixing with modified Y molecular sieve, it is obtained by ammonium exchange treatment. The catalytic activity of this catalyst is not high, and the product quality of middle distillates of jet fuel and diesel oil is average, which needs to be further improved.

However, the above-mentioned hydrocracking catalyst carrier components are simply mechanically mixed, and the components in the catalyst are easily agglomerated into secondary particles, which makes the dispersion of the active components poor, and the prepared catalyst is difficult to exert the best performance.

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