作　　者： ; ; ; ; ;

机构地区： 中国石油大学北京化学工程学院重质油国家重点实验室

出　　处： 《石油学报（石油加工）》 2009年第1期7-13,共7页

摘　　要： 利用催化裂化工业平衡催化剂RGD-1,在提升管催化裂化中试装置和小型固定流化床实验装置上研究了大庆焦化蜡油催化裂化反应过程的生焦特性。采用吡啶红外法表征了积炭催化剂的表面酸性质,并对所生成焦炭的种类进行了分析。结果表明,在与直馏蜡油相同积炭率的条件下,焦化蜡油积炭催化剂的活性损失更大。焦化蜡油催化裂化反应生成的焦炭由吸附焦Cad、脱氢缩合焦Cdh和氢转移焦Cht构成。Cad由碱性氮化物在L酸中心化学吸附所形成,是导致催化剂活性大幅度下降的主要原因,在催化裂化加工焦化蜡油过程中,必须牺牲部分催化剂的L酸中心以供Cad沉积。常规反应条件下的焦炭组成中,Cad的质量分数约占20%;Cdh是焦炭的主要来源,质量分数占总生焦量的60%左右;氢转移焦Cht的生成量受二次反应进行的程度影响很大,适当提高反应温度、缩短反应时间能够抑制氢转移反应的进行,减少Cht的生成量,有利于降低焦炭选择性。 The coking properties of Daqing coking gas oil over commercial equilibrium catalyst RGD 1 were investigated in a confined fluidized bed reactor and pilot test riser FCC unit. The acid properties of RGD-lcatalyst surface was characterized by Py-FTIR, and the species of coke formed by CGO were also analyzed. The results showed that with the same coking rate the deactivation degree of CGO coked catalyst was much higher than VGO coked catalyst. The coke was composed of Cad （Activity center adsorption coke）, Cab （Catalytic condensation coke） and Cht （Hydrogen transfer coke）. Cad was formed as basic nitrogen compounds were adsorbed on L acid sites, which resulted in a great degree deactivation of catalyst. In the FCC direct processing coking gas oil process, a higher conversion often achieved at the cost of part L acid sites of catalyst for Cad. Cad and Cdh accounted for 20 % and 60 % of the coke generated in the conventional reaction conditions, respectively. Cab was the main coke source and its amount changed with the degree of hydrogen transfer reaction. The coke selectivity can be decreased through reducing the amount of Cht by appropriately increasing the temperature and shortening the reaction time to curb the occurrence of hydrogen transfer reaction.

关 键 词： 催化裂化 焦化蜡油 氮化物 吸附焦 失活

领　　域： [石油与天然气工程]