Catalyst for preparing low carbon olefin by petroleum hydrocarbon cracking

Abstract

The invention discloses a catalyst for preparing low-carbon olefins by cracking petroleum hydrocarbons, which comprises 0-70% of clay, 5-99% of inorganic oxides and 1-50% of zeolite based on the weight of the catalyst. The zeolite is 25-100% by weight of MFI structure zeolite and 0-75% by weight of Y-type zeolite, which is characterized in that said MFI structure zeolite contains phosphorus and transition metal M, and its anhydrous chemical expression is expressed as oxide The mass is calculated as (0~0.3)Na 2 O, (0.3~5)Al 2 o 3 , (1.0~10)P 2 o 5 , (0.7~15)M x o y ,(0~10)RE 2 o 3 , (70~98) SiO 2 , wherein, M is selected from one or two metals in Fe, Co, Ni, Cu, Zn, Mo or Mn. The catalyst can enhance the cracking ability of heavy oil macromolecules, improve the reaction conversion rate, and the product has a higher C 2 ＝ ~C 4 ＝ Yield, especially C 3 ＝ yield.

Description

technical field

[0001] The invention relates to a catalyst for producing low-carbon olefins by cracking petroleum hydrocarbons, and more specifically relates to a catalyst for producing low-carbon olefins by cracking petroleum hydrocarbons containing five-membered ring silicalite. Background technique

[0002] Low-carbon olefins are important petrochemical raw materials. The commonly used production methods are steam cracking of natural gas; tube furnace thermal cracking of naphtha or light diesel oil; heat carrier cracking of heavy hydrocarbons and A method for the catalytic conversion of low-carbon alcohols. Conventional catalytic cracking units also produce low-carbon olefins by-products while producing gasoline and light diesel oil, and the yield accounts for less than 15% by weight of the feed oil.

[0003] There are roughly three types of catalysts used when petroleum hydrocarbons are used as raw materials to produce low-carbon olefins by cracking or cracking methods:...