两性-阳离子复配修饰塿土对苯酚的吸附

研究了采用两性表面修饰剂十二烷基二甲基甜菜碱(BS-12)和阳离子表面修饰剂十六烷基三甲基溴化铵(CTMAB)复配修饰塿土后对苯酚的吸附反应和热力学特征,并探讨其吸附机理.结果表明,复配修饰后的土样对苯酚的吸附能力明显增强.20℃时表现为CK(原土)<50BS(50%BS-12)<100BS(100%BS-12)<50BS+25CT(50%BS-12+ 25%CTMAB)<100BS+25CT (100%BS-12+25%CTMAB)<50BS+ 50CT(50%BS-12+50% CTMAB)<100BS+50CT(100%BS-12+50%CTMAB), 40℃时表现为CK(原土)<50BS(50%BS-12)<100BS (100%BS- 12)<50BS+25CT(50%BS-12+25%CTMAB)<50BS+50CT(50%BS-12+50%CTMAB)<100BS+25CT(100%BS-12+25%CTMAB)<100BS+50CT (100%BS-12+50%CTMAB).其吸附等温线可用Henry模型描述.供试土样对苯酚的吸附呈现放热焓减反应特征,属于焓减控制的自发性过程.

Adsorption of phenol on amphoteric-cationic modified lou soil

Using batch experiment, the adsorption of phenol on clay layer (CL) of Lou soil modified with a mixture of amphoteric modifier, dodecyl dimethyl betaine (BS-12), and cationic modifier, cetyltrimethylammonium bromide (CTMAB), were carried out, and its adsorption mechanism was discussed also. The adsorption capacity of phenol on CL of Lou soil could be enhanced significantly by complex modification. The phenol adsorption was ordered by CK(Unmodified soil) <50BS(50%BS-12)<100BS(100%BS-12)<50BS+25CT(50%BS-12+25%CTMAB)<100BS+25CT (100%BS-12+25%CTMAB)<50BS+50CT(50%BS-12+50%CTMAB)<100BS+50CT(100%BS-12+50%CTMAB) at 20℃ and CK(Unmodified soil)<50BS(50%BS–12) <100BS(100%BS-12) <50BS+25CT(50%BS-12+25%CTMAB)< 50BS+50CT(50%BS-12+50%CTMAB)<100BS+25CT(100%BS-12+25%CTMAB)<100BS+50CT(100%BS-12+50%CTMAB) at 40℃. Henry equation was used to describe the phenol adsorption isotherm. The adsorption of phenol on the complex modified soil was a process with characteristics of both exothermic reaction and enthalpy decrease, its spontaneity being controlled by enthalpy decrease.