Batch processing method was employed to study the adsorption law of Tween20(TW20,T) of dodecyl dimethyl betaine(BS 12) amphoteric modified bentonite.Meanwhile,the influence of pH,temperature,differ ent modification proportions of BS 12 and ionic strength on adsorption of TW20 was investigated.The structural feature of amphotericon ion compound modified bentonite was characterized by N2 adsorption-desorption isotherms,X-ray diffraction,Fourier transform infrared spectroscopy and thermogravimetric analysis.The adsorption capacity of BS 12 modified bentonite by 50％ CEC (50BS) of TW20 is notably higher than BS-12 modified bentonite by 100％ CEC(100BS).BS-12 bentonite's absorption quantity to TW20 varied in U-shape curve along with the increase of pH,while decreasing along with the reduction of temperature and the increase of ionic strength.Research on surface properties shows that when there are increments for TW20 modification proportion,total organic carbon content,interlayer spacing,and the specific surface area has a decrease.TW20's absorption onto 50BS got into bentonite interlayer structure through the method of inserting into the layers.External surface absorption is dominant on 100BS.TW20's absorption on BS 12 modified soil sample surface is a coexisting absorption mode of electrostatic adsorption and partitioning absorption.In the adsorption of Cd2+ and phenol experiment,when the modification ratio is 100BS-0.25T,the adsorption capacity of phenol is the largest,and the maximum Cd2+adsorption capacity is at 100BS-0.25T.%采用批处理法,以不同修饰比例的两性修饰剂十二烷基二甲基甜菜碱(BS-12)修饰膨润土为基质,研究pH值、温度及离子强度对BS-12修饰膨润土吸附非离子修饰剂吐温20(TW20,T)的影响,并对两性-非离子复配修饰膨润土进行结构表征,和对Cd2+和苯酚的吸附.结果显示,BS-12按50％CEC修饰膨润土(50BS)对TW20的吸附能力显著高于BS-12按100％CEC修饰膨润土(100BS).BS-12修饰膨润土对TW20的吸附量随pH值增大呈U型变化,随温度降低、离子强度增加而下降,TW20在BS-12修饰土的吸附是静电吸附和分配吸附共存.TW20修饰比例增大,有机碳含量增高,层间距增大,比表面积减小.TW20在50BS上通过插层进入膨润土层间,在100BS上以外表面吸附为主.在修饰比例为100BS-0.25T时对苯酚和Cd2+的吸附效果最好.
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