Diesel fuel fraction depth desulfurization and dearomatization catalyst and prep. thereof

Abstract

The present invention is one kind of catalyst for producing low-sulfur and low-arene clean diesel oil and its preparation. The catalyst has modified Y-type molecular sieve as its acid component, andthe modification process of the molecular sieve is to make siliceous organic matter with relatively large dynamic diameter contact with the molecular sieve and combine with acid centers on the surface of the molecular sieve while maintaining the acid centers inside the molecular sieve pore passages of the molecular sieve under certain conditions. The catalyst is used in producing low-sulfur and low-arene clean diesel oil and has the advantages of high diesel oil yield, high cetane number of diesel oil product, low sulfur, nitrogen and arene content in diesel oil, etc.

Description

1. Technical field [0001] The invention discloses a desulfurization and dearomatization catalyst for producing clean diesel oil and a preparation method thereof. Specifically, it is a deep desulfurization and dearomatization catalyst containing modified Y zeolite and a preparation method thereof. 2. Background technology [0002] In order to meet the requirements of product quality and environmental protection regulations, petroleum products must be refined before sale to remove harmful substances. Current environmental protection regulations have put forward stricter standards for sulfur, aromatics content and cetane number in diesel, although Now the removal of sulfur in diesel fractions is quite mature, and a variety of catalysts with excellent performance have been introduced, but the aromatic hydrocarbon saturation capacity of these catalysts is very low. Generally speaking, aromatic hydrocarbon saturation is more difficult than sulfur removal, and aromatic hydrocarbon ...

AI Technical Summary

Problems solved by technology

However, because hydrogen-type molecular sieves have more acid sites, stronger acidity, and widely distributed acid sites, some acid sites distributed on the outer surface of molecular sieves have no selectivity. Small molecule, low yield of diesel oil, in order to solve this problem, people carry out further treatment to Y-type molecular sieve, mainly carry out means such as chemical dealumination, water vapor dealumination and introduction of auxiliary components, etc. The Y-type molecular sieve is treated by chemical methods such as dealumination, slurrying with some compounds and exchange with aluminum salts, and then adding phosphorus-containing compounds to improve the stability and selectivity of the catalyst and reduce the coking performance of the catalyst.

However, the common problem in the current methods is that the processing steps are complicated, and the molecular sieve is greatly damaged during dealumination, especially during acid dealumination, which reduces the crystallinity of the molecular sieve. In addition, selective dealumination and accurate control of local acidity cannot be performed, resulting in The acidity of molecular sieve after dealumination cannot meet the actual needs