Catalyst containing modified molecular sieve and preparation method thereof

Abstract

The invention relates to a catalytic cracking catalyst containing a modified molecular sieve and a preparation method thereof. In terms of 100% mass percentage, the catalyst contains 10-55% of the modified molecular sieve on dry basis, 10-80% of clay on dry basis, 0-40% of inorganic oxide in terms of oxide and 5-40% of a binder in terms of oxide. The modified molecular sieve is prepared by the method of: firstly dissolving a compound containing IIIB metal ions of the periodic table of elements in water or acid to form a solution, conducting mixing with a precipitating agent, an organic complexing agent and / or dispersant, and performing stirring for at least 10min to form III B element-containing precipitate; mixing the obtained precipitate with a molecular sieve slurry, and conducting stirring at 5-100DEG C for at least 10min so as to obtain a mixed slurry of the III B element-containing precipitate and the molecular sieve, and conducting spray drying and or without roasting. The catalyst disclosed by the invention has excellent activity stability and resistance to heavy metal pollution.

Description

technical field [0001] The invention relates to a catalytic cracking catalyst, in particular to a catalytic cracking catalyst with excellent activity stability and anti-heavy metal pollution performance. Background technique [0002] Crude oil is increasingly heavy and inferior. Efficient processing of heavy oil and blending of residual oil has become an urgent need for refiners to improve processing capacity and obtain higher profits. Catalytic cracking is the most important process of heavy oil processing. Due to its significant advantages such as high conversion efficiency of heavy oil, good product quality, non-hydrogenation and low operating pressure, it occupies a pivotal position in the process of processing heavy oil in refineries. It is the refinery's profit main source of . According to statistics, there are currently about 420 sets of catalytic cracking units in the world. The largest single set of catalytic cracking units has reached 10 million tons per year, wi...

AI Technical Summary

Problems solved by technology

It has been found that rare earth ions exchange with cations such as sodium in molecular sieves, migrate into molecular sieves, and play a role in improving the activity and stability of molecular sieves. However, once the ion-exchanged rare earths come into contact with vanadium, they are easy to break away from the framework structure of molecular sieves and form vanadium Acidic rare earths, on the contrary, make the structural stability of molecular sieves worse; and rare earths that exist in the form of independent phases can be used to trap heavy metals in the process of catalytic cracking reaction due to their different positions and states, and play the role of anti-heavy metals

Therefore, the above-mentioned rare earth molecular sieve prepared by rare earth ion exchange does not contain rare earth in independent phase, so its ability to resist heavy metal pollution is insufficient

[0010] The rare earth-containing Y-type molecular sieve prepared by the precipitation method, even if a rare earth precipitate is formed and contains a separate phase of rare earth, the particles of the rare earth precipitate are large, which is not conducive to uniform dispersion on the surface of the molecular sieve, and is not conducive to effective contact with heavy metals. , Capture heavy metals in time

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