Ultrastable Y-type RE molecular sieve active component and its prepn process

Abstract

The active component of ultrastable Y-type RE molecular sieve is composite modified Y-zeolite containing RE oxide 8-25 wt%, P 0.1-3.0 wt% and sodium oxide 0.3-2.5 wt%, and with degree of crystallization 30-55 % and unit cell parameter 2.455-2.477 nm. It is prepared with Y-zeolite as material and through the steps of exchange with RE and the first roasting to obtain RE-Na Y-zeolite; reaction with RE, reaction with P-containing compound, and the second roasting. The ultrastable Y-type RE molecular sieve is used as the active component of cracking catalyst and has the obvious effect of lowering olefin content in gasoline and the features of resulting in moderate coke yield and high diesel oil yield. The preparation process is simple and high in the utilization of the modifying elements.

Description

technical field [0001] The invention relates to an active component of an ultra-stable rare earth Y molecular sieve and a preparation method thereof, more specifically, an active component of a cracking catalyst suitable for reducing gasoline olefins in a catalytic cracking process and a preparation method thereof. Background technique [0002] The high olefin content in gasoline is one of the main causes of high vehicle exhaust emissions. As many as 80% of the total domestic gasoline has an olefin content of 40-60% in cracked gasoline, which is far from the new national standard (the olefin content does not exceed 35v%). The development of cracking catalysts with strong ability to reduce olefins has become the research focus in the field of catalysis. The preparation of active components is a key technology in the development of olefin-reducing catalysts. [0003] From the perspective of the international FCC catalyst market, the well-known AKZO catalyst company and GRACE...

AI Technical Summary

Problems solved by technology

CN1217231A discloses the preparation method of phosphorus-containing zeolite molecular sieve, impregnating modified faujasite molecular sieve with phosphorus-containing solution, drying, and roasting at 450-600°C for more than 0.5 hours. The catalyst containing this molecular sieve increases the yield of diesel oil, but there is no description The effect of reducing gasoline olefins

[0006] To sum up, the olefin-reducing active component prepared by the prior art has a certain olefin-reducing ability, but the main disadvantage is that the preparation process is complex and the raw materials are expensive. For example, the cost of ZSM-5 is about 60,000 yuan / ton. Using ZSM -5 As the main active component for reducing olefins, the manufacturing cost of the catalyst will be doubled. In addition, the existing active components will reduce the yield of light oil, especially diesel oil, while highlighting the function of reducing olefins