活性炭吸附脱硫机理的硬软酸碱理论研究  

Hard-Soft Acid-Base Investigation of Adsorptive Desulfurization by Activated Carbon

作　　者：于维钊[1] 郑经堂[1] 何小超[1] 

机构地区：[1]中国石油大学(华东)重质油国家重点实验室,山东东营257061

出　　处：《石油化工》2008年第12期1270-1275,共6页Petrochemical Technology

摘　　要：以噻吩为吸附脱除对象,分别以环己烷、正庚烷或正癸烷为烷烃的模型化合物,环己烯和甲苯为烯烃和芳烃的模型化合物,模拟流化催化裂化汽油的组分,配制模型汽油。考察了活性炭在过硫酸铵氧化处理前后,对含不同竞争吸附质的模型汽油中噻吩的吸附脱除性能,并采用量子化学方法计算得到噻吩和竞争吸附质的化学硬度,根据硬软酸碱理论分析了不同吸附质与噻吩竞争吸附作用的强弱。结果表明,化学硬度与噻吩差别较大的烷烃(环己烷、正庚烷和正癸烷)与噻吩的竞争吸附作用/不明显,而化学硬度与噻吩较接近的环己烯和甲苯则与噻吩的竞争吸附作用较强,特别是甲苯。氧化处理后的活性炭由于表面含氧基团的增加导致表面局部化学硬度改变,也是它对噻吩的吸附作用增强的原因之一。Adsorptive desulfurization performance of activated carbon, both before and after oxidation treatment with ammonium persulfate, for simulated fluid catalytic cracking （FCC） gasoline was investigated. The cyclohexane, n-heptane and n-decane in simulated FCC gasoline were presented as model alkanes; cyclohexene and toluene were presented as model olefin and aromatics respectively. Thiophene was the object of adsorptive desulfurization. Chemical hardness of both thiophene and competitive compounds were calculated by quantum chemistry method. According to hard-soft acid- base theory, alkanes, with greater difference in chemical hardness from thiophene, are less competitive in adsorption than thiophene, while cyclohexene and toluene, whose chemical hardness is closer to thiophene, are more competitive in adsorption than thiophene. Experimental results conformed to the theoretical analysis. Oxidation treatment of activated carbon leaded to increase of oxygen-containing groups on its surface, which altered the local chemical hardness and was an important reason for adsorption enhancement of thiophene.

关 键 词：活性炭 吸附脱硫 噻吩 流化催化裂化汽油 硬软酸碱 

分 类 号：TE624.5[石油与天然气工程—油气加工工程]