羧酸盐/玉米芯接枝共聚物的制备及其对Cd^(2+)和Ni^(2+)的吸附  

Preparation of carboxylate/corncob graft copolymer for adsorption of Cd^(2+) and Ni^(2+)

作　　者：唐仕荣[1] 蔡望秋 陈尚龙[1] Tang Shirong;Cai Wangqiu;Chen Shanglong(Jiangsu Key Construction Laboratory of Food Resources Development and Quality Safe,Xuzhou University of Technology,Xuzhou 221018)

机构地区：[1]徐州工程学院江苏省食品资源开发与质量安全重点建设实验室,徐州221018

出　　处：《化工新型材料》2022年第2期192-197,201,共7页New Chemical Materials

基　　金：国家自然科学基金青年项目(31701566)。

摘　　要：利用原子转移自由基聚合技术在玉米芯表面引发丙烯酸甲酯发生聚合反应,再分别通过NaOH和t-BuOK进行水解,制备出两种羧酸盐/玉米芯接枝共聚物(MC-g-PAA-Na和MC-g-PAA-K)。结果表明:两种羧酸盐/玉米芯接枝共聚物吸附Cd^(2+)和Ni^(2+)是自发、吸热且伴随焓增加的过程,该过程更符合Langmuir模型,属于单层吸附,同时遵循准二级反应机理,属于化学吸附。MC-g-PAA-K对Cd^(2+)和Ni^(2+)的最大吸附量分别为158.2mg/g和95.51mg/g,是MC-g-PAA-Na对Cd^(2+)和Ni^(2+)最大吸附量的2.05倍和1.93倍,表明采用位阻较大的t-BuOK溶液可以有效地提高羧酸盐/玉米芯接枝共聚物对重金属离子的吸附容量。The polymerization reaction of methyl acrylate(MA)was performed to immobilize poly(methyl acrylate)(PMA)brushes on the corncobs using atom transfer radical polymerization(ATRP)technology.Two kinds of carboxylate/corncobs graft copolymer(MC-g-PAA-Na and MC-g-PAA-K)were prepared through hydrolysis with NaOH and t-BuOK in order to introduce high densities of carboxyl groups on the corncobs,respectively.Thermodynamic study shown that the adsorptions of Cd^(2+) and Ni^(2+) by the copolymers were spontaneous,endothermic,and accompanied by an increase in randomness.These processes were more in line with Langmuir model,belong to single-layer adsorption.Following the pseudo-second-order reaction mechanism,they was belong to chemical adsorption.The maximum adsorption capacities of MC-g-PAA-K for Cd^(2+) and Ni^(2+) were 158.2mg/g and 95.51mg/g,respectively,which were 2.05 times and 1.93 times of the maximum adsorption capacities of MC-g-PAA-Na for Cd^(2+) and Ni^(2+),indicating that the adsorption capacities for heavy metal ions can be effectively improved through hydrolysis by t-BuOK with larger steric hindrance.

关 键 词：羧酸盐 接枝共聚物 重金属离子 吸附 原子转移自由基聚合 

分 类 号：TB324[一般工业技术—材料科学与工程] X52[环境科学与工程—环境工程]