Modification of silica gel and its selective adsorption of cu2 from aqueous solution

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Research of Materials Science December 2014, Volume 3, Issue 4, PP.74-81

Modification of Silica gel and Its Selective Adsorption of Cu2+ from Aqueous Solution Hanpei Yang 1,2,3#, Mihong Yu 2, Yanmei Tu 2, Junming Wu 1,2 1. Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing Jiangsu 210098, China 2. College of Environment, Hohai University, Nanjing Jiangsu 210098, China 3. Huaian Research Institute of Hohai University, Huaian Jiangsu 223001, China

Abstract In the present work, the silica gel with chemical and mechanical stability were choose as a matrix for further modification, endowed with given specific physical and chemical properties for the removal of Cu2+ in water. The research suggested that, with the activation by methanesulfonic acid, the amination were achieved by chemical bonding between γ-triethoxysilylpropylamine and hydroxyl groups on the surfaces of silica gel. Furthermore, the acrylonitrile was covalently attached by the copolymerization between amino silica gel and acrylonitrile with the initiation of azobisisobutyronitrile. Finally, abundant amino and hydroxyl groups were linked onto the surface of modified silica gel through the amidoximation reaction. The surface nature of modified silica gel was illustrated by infrared spectrum measurement. The significant enhancement of the adsorption of aqueous Cu2+ on modified silica gel were observed and the effects of contact time, initial concentration of Cu 2+, pH value of the solution were investigated. The adsorption isotherm and kinetics were calculated and the adsorption mechanism of Cu 2+ on amidoximed silica gel was proposed. Keywords: Adsorption; Silica Gel; Surface Modification; Heavy Metal; Cu2+; Covalent Grafting

硅胶的表面改性及其对水体铜离子的吸附性能 研究* 杨汉培 1,2,3,俞咪虹 2,涂艳梅 2,吴俊明 1,2 1.河海大学 浅水湖泊综合治理与资源开发教育部重点实验室,江苏 南京 210098 2. 河海大学 环境学院,江苏 南京 210098 3. 河海大学 淮安研究院,江苏 淮安 223001 摘

要:尝试利用化学性质稳定、机械强度高的硅胶吸附剂,通过定向表面改性,赋予其特定理、化性质,以脱除水体

重金属Cu2+。研究结果表明,原始硅胶经甲磺酸活化,借助硅胶表面富含的-OH基团,化学共价键联γ-氨丙基三乙氧基硅 烷,使硅胶表面借助硅氧基嫁接-NH2基团,进一步地,在偶氮二异丁腈引发下,嫁接丙烯腈,经偕胺肟化聚丙烯腈基团, 使改性硅胶吸附剂表面富含-NH2 和-OH,显著提升其对水体Cu2+的选择性吸附。利用红外光谱探明了硅胶表面改性的机 制,系统探讨了接触时间、Cu2+初始浓度、溶液pH值等因素对改性硅胶吸附性能的影响,通过改性硅胶表面Cu2+的等温 吸附平衡和吸附动力学研究,初步揭示了改性硅胶的化学吸附实质。 关键词:吸附;硅胶;表面改性;重金属;Cu2+;共价嫁接

引言 *

河海大学淮安研究院开放基金资助项目。 - 74 http://www.ivypub.org/rms


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