海洋科学Issue(9)：61-67,7.
氨基酸在改性黏土上的吸附机制研究
A mechanistic study of the adsorption of amino acid onto modified clays
摘要
Abstract
Algal organic materials (AOMs) has critical influence on the REs. Amino acid is an important ingredient of AOMs, for what is with various function groups and is construction units of proteins and polypeptide. In order to obtain a mechanic understanding of the adsorption of amino acid on modified clays, the adsorption of four amino acids, including lysine, glutamic, glycine and histidine, onto modified clays was studied as a function of modifier dosage, pH and ionic strength through well controlled batch adsorption experiments. The kinetics experiments data is fitted well by a pseudo-second order model. The mechanism of amino acid on modified clays is complicated and both the surface adsorption and intraparticle diffusion contribute to the rate determining step. The adsorbed amount of amino acids is increased with adding appropriate dosage of modifier PACl, and the optimum mass ratio is 5%. The maximum adsorption of Lys., Glu., Gly. and His. are 827, 712.56, 723.14 and 732.56μmol/g, respectively. The equilibrium data is well described by C isotherm curve. The rmodynamic parameters are calculated, e.g. the value of gibbs free energy for Lys., Glu., Gly. and His. are −1.99, −2.41, −3.16 and −2.94 kJ/mol, respectively. And the results show that the adsorption of amino acid on modified clays is a spontaneous process. The adsorption of amino acid on modified clays is highly dependent on pH, and decreases with increasing ionic strength.关键词
氨基酸/改性黏土/动力学/吸附等温线/pH/离子强度Key words
Amino acid/Modified clays/Adsorption kinetics/Adsorption isotherm/pH/Ionic strength分类
资源环境引用本文复制引用
林勇新,曹西华,宋秀贤,俞志明..氨基酸在改性黏土上的吸附机制研究[J].海洋科学,2013,(9):61-67,7.基金项目
国家重点基础研究发展计划(973计划)(2010CB428706) （973计划）
国家自然科学基金青年项目(40906055) （40906055）
国家自然科学基金创新群体项目(41121064) （41121064）
河北省省级预算项目(2013045661) （2013045661）
