阴、阳离子表面活性剂在粘土矿物表面的混合吸附

Mixed Adsorption of Anionic and Cationic Surfactants on Clay Minerals

研究了２５℃时十二烷基硫酸钠（ＳＤＳ）和溴化十六烷基吡啶（ＣＰＢ）自其单组分水溶液及其混合水溶液在高岭土、碳酸钙、石英砂上的吸附．结果表明，ＳＤＳ在高岭土和碳酸钙上的吸附等温线在ＳＤＳ的临界胶束浓度（ＣＭＣ）值以前出现最大值，ＳＤＳ在石英砂上几乎不吸附；ＣＰＢ在高岭土上的吸附等温线为Ｌａｎｇｍｕｉｒ型，而在碳酸钙、石英砂上几乎不吸附；在ＳＤＳ与ＣＰＢ的混合体系中，ＳＤＳ在高岭土、碳酸钙、石英砂上的吸附都增大，相应地，ＣＰＢ在高岭土上的吸附减小，在碳酸钙上的吸附增大，并且随吸附后ＳＤＳ／ＣＰＢ摩尔比的不同，出现吸附最大值．文中成功地将吸附等温线与吸附平衡溶液的电导率曲线有效地结合起来，分析了实验结果，提出了可能的吸附机理．

The adsorption of Sodium Dodecyl Sulfate(SDS)and Cetylpyridinium Bromide(CPB)from their single aqueous solutions and SDS-CPB mixed solutions on kaolinite,calcium carbonate(CaCO3)and silica(SiO2) at 25℃ had beeninvestigated respectively.The results showed that the adsorption isotherms of SDS on both kaolinite and CaCO3 showed maxima before the critical micelle concentration(CMC),whereas the adsorption of SDS on SiO2 was hardly to be measured experimentally; The adsorption of CPB on kaolinite could be analysed in terms of Langmuir equation while the adsorption capacities of CPB on CaCO3 and SiO2 were rather low; In SDS-CPB mixed solutions,the adsorptions of SDS on kaolinite,CaCO3 and SiO2 were all enhanced and the adsorption of CPB were decreased on kaolinite but increased on CaCO3 and showed maxima with the difference of SDS/CPB molar ratio.The adsorption isotherms had been combined with the conductivity curves of equilibrium solution effectively,the results had been analysed and the probable adsorption mechanisms had been proposed.