黄原酸改性交联面包酵母的制备及对Pb(Ⅱ)的吸附特性  

Preparation of xanthate-functionalized cross-linked baker's yeast and its adsorption characteristics for Pb(Ⅱ)

作　　者：段正洋 胡柠檬 李天国[2] DUAN Zhengyang;HU Ningmeng;LI Tianguo(College of Resources,Environment and Chemistry,Chuxiong Normal University,Chuxiong 675000,Yunnan,China;College of Resources and Environment,Yunnan Agricultural University,Kunming 650201,Yunnan,China)

机构地区：[1]楚雄师范学院资源环境与化学学院,云南楚雄675000 [2]云南农业大学资源与环境学院,云南昆明650201

出　　处：《化工进展》2022年第7期3925-3937,共13页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(41701362);云南省地方高校联合专项——青年项目(202101BA070001-012);云南省教育厅基金(2019J0397);楚雄师范学院博士科研启动基金(JBS2002)。

摘　　要：以面包酵母为基材,通过两步法制备得到黄原酸改性交联面包酵母(XCBY),并应用于水溶液中Pb(Ⅱ)的去除研究,原始面包酵母、XCBY和XCBY-Pb(Ⅱ)的理化特性分别采用SRA、SEM、EDS、FTIR、XRD和XPS等手段进行表征,研究了溶液pH、吸附剂用量、Pb(Ⅱ)初始浓度等因素对XCBY吸附性能的影响,并探讨了吸附动力学、等温线、热力学和XCBY的再生性能。结果表明,原始面包酵母经交联和黄原酸改性后,其细胞形态没有明显变化,且对Pb(Ⅱ)的吸附性能得到明显提高。XCBY对Pb(Ⅱ)的吸附过程更符合伪二阶动力学和Langmuir吸附等温线模型,热力学分析表明吸附过程为自发的吸热反应。在30℃、吸附时间为40min的条件下,Langmuir吸附等温线拟合结果显示XCBY对Pb(Ⅱ)的最大吸附量达到319.91mg/g。此外,Pb(Ⅱ)在XCBY上的吸附机制主要依赖于XCBY表面—NH_(2)的配位作用、—OH的离子交换以及—C(=S)—S-的螯合作用。指出作为一种简便经济的面包酵母化学改性方法,XCBY在含重金属离子废水的吸附处理方面具有潜在的发展应用前景。Xanthate-functionalized cross-linked baker's yeast(XCBY)was prepared by a two-step method and applied to remove Pb(Ⅱ)from aqueous solutions.The physicochemical characteristics of non-modified baker's yeast,XCBY and Pb(Ⅱ)-loaded XCBY were characterized by SRA,SEM,EDS,FTIR,XRD,and XPS.The impacts of operating parameters of pH,adsorbent dosage,initial concentration of Pb(Ⅱ)on the adsorption performance of XCBY were systematically investigated,and the adsorption kinetics,isotherm,thermodynamics and regeneration performance of XCBY were discussed.The results showed that the original baker's yeast had no significant change in cell morphology after crosslinking and xanthic acid modification,and its adsorption performance for Pb(Ⅱ)was significantly improved.Pseudo-second-order and Langmuir isotherm models effectively described the adsorption behavior of XCBY,and the thermodynamic analysis revealed that the adsorption process of Pb(Ⅱ)onto XCBY was spontaneous and endothermic.The adsorption process for Pb(Ⅱ)reached equilibrium at 30℃in 40min with a maximum adsorption capacity of 319.91mg/g from the Langmuir isotherm model.Additionally,the adsorption mechanism of Pb(Ⅱ)on XCBY mainly depended on the coordination of—NH_(2),ion exchange of—OH and complexation of—C(=S)—S-.As a facile and economical chemical modification method of baker's yeast,the modified material was a potential and prospective adsorbent for use in the treatment of heavy metal-bearing wastewater.

关 键 词：面包酵母 黄原酸改性 交联 废水 吸附机制 

分 类 号：X705[环境科学与工程—环境工程] X712