摘要
利用香蕉皮(BP)为原料,制备盐酸改性香蕉皮(HABP)和香蕉皮负载铜离子(NCBP)吸附材料,评价三种材料对地下水中硝酸盐氮的吸附效果。试验结果表明:当pH分别为2、1和4时,吸附剂剂量分别为0.10、0.06和0.02g,反应时间为120min时,BP、HABP和NCBP三种材料对体积为50 mL质量浓度为20 mg/L含硝酸盐氮溶液的最高去除率分别为16.5%、57.6%和58.5%;共存离子对NO_3^--N吸附影响较小,其顺序为:Cl^-<SO_4^(2-)<HCO_3^-<HPO_4^(2-);伪二级动力学方程能较好地拟合三种材料对NO_3^--N的吸附动力学过程,揭示其吸附主要是离子交换吸附;Langmuir方程和Frenudlich方程均能较好地拟合三种材料对NO_3^--N的等温吸附过程,表明其吸附既有单分子层吸附又有多分子层吸附,BP、HABP和NCBP对的NO_3^--N最大吸附量分别为3.57、39.84和81.30mg/g。热力学研究表明,NO_3^--N在BP和HABP表面的吸附是一个自发,放热的物理吸附过程,在NCBP表面的吸附是一个自发,吸热既有化学吸附又有物理吸附过程。
Hydrochloric acid modified banana peel(HABP)and banana peel supported copper ion(NCBP)were prepared from banana peel(BP)and their adsorption of nitrate in ground water was studied.The results of BP,HABP and NCBP showed that when the pH was 2,1and 4,the absorbate dosage was 0.1,0.06,0.02 g,the reaction time was 120 min,the volume of water was 50 mL and the concentration of nitrate was 20mg/L,the highest removal rates were 16.5%,57.6% and 58.5%,respectively.The effect of competitive ions on nitrate removal rate was little,and the order of competitive effect was Cl^-<SO_4^(2-)<HCO_3^-<HPO_4^(2-).The kinetic adsorption process of NO_3^--N ions on three biosorbents was fitted by pseudosecond-order kinetic model,and the adsorption was mainly ion exchange adsorption.Langmuir equation and Frenudlich equation could simulate their isothermal adsorption process of NO_3^--N,indicating that the adsorption of NO_3^--N ions was complex including monolayer and multilayer adsorption.The maximum adsorption capacity of BP,HABP and NCBP was 3.57,39.84 and 81.30 mg/g.The thermodynamics analysis showed that the adsoption process of NO_3^--N ions on BF and HABF was spontaneous exothermic physical adsorption,but the adsoption process of NO3-N ions on NCBP was spontaneous endothermic physical and chemical adsorption.
出处
《化学世界》
CAS
CSCD
2017年第9期538-546,共9页
Chemical World
基金
国家级大学生创新创业训练计划(No.201510439050)资助项目
关键词
盐酸改性香蕉皮
香蕉皮负载铜离子
硝酸盐氮
吸附动力学
热力学
hydrochloric acid modified banana peel
copper ion supported on banana peel
nitrate
adsorption kinetics
thermodynamics
