标题：Synthesis, aggregation behavior of novel cationic silicone surfactants in aqueous solution and their application in metal extraction
作者：Fang, Liying; Tan, Jinglin; Zheng, Yan; Yang, Ge; Yu, Jiangtao; Feng, Shengyu
作者机构：[Fang, Liying; Zheng, Yan; Yang, Ge; Yu, Jiangtao; Feng, Shengyu] Shandong Univ, Sch Chem & Chem Engn, Minist Educ, Key Lab Special Funct Aggregated M 更多
通讯作者地址：[Feng, SY]Shandong Univ, Sch Chem & Chem Engn, Minist Educ, Key Lab Special Funct Aggregated Mat, Jinan 250100, Peoples R China;[Feng, SY]Shandong Uni 更多
来源：JOURNAL OF MOLECULAR LIQUIDS
关键词：Cationic silicone surfactants; Aggregation behavior; Metal extraction
摘要：Two cationic silicone surfactants, 3-[tri-(trimethylsiloxy)]isilylpropylpyridinium chloride (Si(4)pyrCl) and N-methyl-3-1tri-(trimethylsiloxy)lsilylpropylpiperidinium chloride (Si(4)pipCl), were synthesized. Their aggregation behavior in aqueous solution was investigated through analyses of surface tension, electrical conductivity, dynamic light scattering (DLS), and transmission electron microscopy (TEM). Surface-tension measurements showed that the two cationic silicone surfactants decreased the surface tension of water to almost 20 mN m(-1). This result indicated the surfactants' remarkable surface activity. The effects of inorganic salts, sodium chloride, sodium bromide, sodium iodide and sodium sulfate, on the aggregation behavior of Si(4)pyrCl and Si(4)pipCl were systematically explored. Results showed that the aggregation of Si(4)pyrCl and Si(4)pipCl was promoted by the addition of salts and that aggregation ability followed the order of Nal > NaBr > Na2SO4> NaCl. Thermodynamic parameters obtained from electrical-conductivity measurements indicated that the micellization of Si(4)pyrCl and Si(4)pipCl was entropy driven. Spherical aggregates with diameters ranging from 200 nm to 600 nm were observed by TEM, and the aggregates' diameter distribution was obtained by DLS. The extraction behavior on several metal ions (Co (II), Mn (II), Fe (III), Ni (II), Cu (II), Al (III), Sn (IV), Zn (II), Ce (III), Li (I), Mg (II), Au (III), and Pd (II)) in chloroform by the surfactants in chloroform was studied for the first time. Results showed that Si(4)pipCl and Si(4)pyrCl had good extraction ability for Au (III) and Pd (II). (C) 2017 Elsevier B.V. All rights reserved.