Preparation And Performance Evaluation Of RFCC Catalysts With HSY As Active Component

Modified Y zeolite is usually used as the active component of fluid catalytic cracking (FCC) catalyst. Conventional Y zeolite sized about l?m shows a good performance in the catalytic cracking of light oil, but can not adapt to heavy oil cracking. HSY zeolites (silicon aluminum ratio?6.0, the particle size of 200-400 nm) not only have larger surface area and the shorter tunnel, favoring the cracking of the heavy oil molecules and accelerating the diffusion of cracking products, but also have high structural stability. In order to investigate the effect of modification methods and properties of HSY zeolite in heavy oil catalytic cracking, we prepared a series of catalysts including HSY-USY, HSY-LaHY and HSY-LaY by diverse Na type HSY material.(1) Study on the modified HSY-USY catalysts showed that the residue catalytic cracking activity was obviously improved by rare earth ion exchange. On the basis of the above, phosphorus modification can not only improve the catalytic cracking activity, but also reduce the coke yield. It showed a heavy oil conversion of 92.6%, with a gasoline yield of 55.3% and a coke yield of only 4%.(2) Study on the HSY-LaHY catalysts showed that conversion rate and total liquid yield of the samples, prepared under optimized conditions by modifying ammonium bofore lanthanum, was 88.8% and 82.1% respectively, while the diesel-gasoline ratio was as low as 0.20.(3) Study on the HSY-LaHY catalysts showed that the samples prepared by calcination mode A had the advantages of high heavy oil conversion, high liquor and LPG yield, while the samples prepared by calcination mode B had the characteristic of high light oil yield, high gasoline yield and low coke yield.(4) With the same treatment conditions, higher Si2O3/Al2O3 ratio of HSY zeolite favored the performance of residue catalytic cracking. Dispite the same ratio of Si2O3/Al2O3 ratio of HSY, the difference of its synthesis process also affected the residue catalytic cracking activity and product distribution.(5) Compared with industrial reference agent, the DUT catalysts, made by the above different process from modifed HSY zeolite, showed excellent performance of residue catalytic cracking. The product distribution can be manipulated to adapt to different product demand of many enterprises through varying the modification process. It has very important significance in economic benefits for the oil refinery enterprises.