摘要
生物吸附在贵金属的回收中具有较高的应用潜力.本研究以毛霉菌(Mucor varians)菌株(CGMCC 3.02549)为菌种资源,探究了毛霉菌吸附Au^(3+)的影响因素,包括初始Au^(3+)浓度、温度和pH值,研究了毛霉菌吸附Au^(3+)的动力学和热力学特性.结果表明,随着初始Au^(3+)浓度升高,毛霉菌的吸附率降低,吸附容量增高;吸附率随着温度的升高而增加;pH对毛霉菌吸附Au^(3+)的效果影响明显,pH为3时吸附效果最佳.毛霉菌对Au^(3+)的等温吸附过程更符合Langmuir方程(R2=0.985),最大吸附量为325.418 mg·g^(-1).拟二级动力学方程更适合描述Au^(3+)在毛霉菌上的吸附动力学(R2=0.910~0.922).通过热力学分析得出,毛霉菌吸附Au^(3+)是自发的吸热过程.傅里叶红外光谱、X射线光电子能谱、X射线衍射和透射电镜分析表明,回收产物为金纳米颗粒,羰基和羟基是起主要作用的官能团.
Biosorption is emerging as a promising approach to recover precious metals.This study aims to examine the effects of initial gold concentrations,temperature and solution p H on gold biosorption by Mucor varians and to explore biosorption kinetics and thermodynamics models.The results showed that the biosorption capacity increased while the biosorption efficiency decreased with the increase of initial gold concentrations. Biosorption efficiency also increased with the increase of temperature.Meanwhile,biosoption efficiency was strongly influenced by solution p H and the optimized solution p H was 3.The biosorption process matched Langmuir model best and provided a good correlation for the biosorption（ R2= 0.985） with maximum capacity of 325.418 mg·g-1.Moreover,the pseudo-second-order kinetics was suitable for the experimental data（ R2= 0.910 ~ 0.922）.The thermodynamic parameters revealed that the biosorption process was spontaneous and endothermic. Finally,FT-IR,XPS,XRD and TEM investigation revealed that Mucor varians could recover gold as nanoparticles,and hydroxyl and carbonyl were the main effective functional groups involved in the process.
作者
郭雯颖
朱能武
李遥
GUO Wenying;ZHU Nengwu;LI Yao(School of Environment and Energy, South China University of Technology, Guangzhou 510006;Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006;Guangdong Environmental Protection Key Laboratory of Solid Waste Treatment and Recycling, Guangzhou 510006;Guangdong Engineering and Technology Research Center for Environmental Nanomaterials, Guangzhou 510006)
出处
《环境科学学报》
CAS
CSCD
北大核心
2018年第5期1820-1827,共8页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.31178191)
广州市产学研协同创新重大专项(No.201604020055)
广东省科技计划项目(No.2017A020216013)
中央高校基本科研业务费培育项目(No.2017PY012)~~
关键词
毛霉菌
金纳米颗粒
生物吸附
动力学
热力学
还原机制
Mucor varians
gold nanoparticles
biosorption
kinetics
thermodynamics
reduction mechanism
