焦化蜡油催化裂化产物氮分布的研究

Studies on nitrogen distribution in products during catalytic cracking of coker gas oil

The nitrogen distribution in products during catalytic cracking of coker gas oil(CGO) was investigated in a laboratory two-staged riser catalytic cracking(TSRFCC) experimental unit with Kelamayi CGO as feedstock.The results showed that operation parameters,such as reaction temperature,catalyst-oil ratio and residence time,all could significantly affect the nitrogen distribution in the products.The nitrogen in the gas product and gasoline fractions decreased with the increase of reaction temperature and/or residence time,which could promote the thermal cracking.However,the nitrogen in gas product and gasoline fractions increased with the increase of catalyst-oil ratio,which could mainly enhance the catalytic cracking.On the whole,after CGO conversion,about 50% of the total nitrogen could produce nitrogen-containing coke over catalyst,and 20% of the total nitrogen remained in heavy oil,while only a little of the total nitrogen could be transfered into diesel,gasoline and gas products.