Preparation of new biosorbents based on poly-γ-glutamic acid and its adsorption of heavy metal ions

4th International Conference on Water Resource and Environment

地球科学;生态环境科学

Mu, R.M.^1 ; Zhang, Z.^1,2 ; Li, X.C.^3 ; Liu, D.^1 ; Zhao, Y.L.^1

School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, China^1

Wuxi Municipal Design Institute Co. Ltd., Wuxi, Jiangsu, China^2

Shandong Environmental Audits and Reception Center of Construction Projects, Jinan, Shandong, China^3

关键词: Adsorption capacities;    Adsorption effect;    Adsorption process;    Initial concentration;    Magnetic particle;    Natural resolution;    Poly-gamma-glutamic acid;    Strength performance;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/191/1/012061/pdf
DOI  :  10.1088/1755-1315/191/1/012061

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

In this paper, adsorption effects and characteristics of heavy metal ions by poly-γ-glutamic acid (γ-PGA) and its two complexes (γ-PGA/Gelatin and γ-PGA/Fe3O4) were studied. The adsorption capacity of Cu2+, Pb2+ and Cd2+ with initial concentration of 100 mg/L by unmodified γ-PGA is 1158 mg/g, 1129 mg/g and 301 mg/g, respectively. However, γ-PGA is easy to dissolve in water, which is not conducive to the treatment of heavy metal wastewater under flow state, neither to its reuse. The γ-PGA/Gelatin was prepared by crosslinking γ-PGA with gelatin to enhance γ-PGA's mechanical strength and adsorption stability. Moreover, Fe3O4 magnetic particles are also the ideal carrier of γ-PGA, which not only improves the strength performance of γ-PGA but also enhances the repetition rate of γ-PGA. The γ-PGA/Fe3O4 magnetic particles were prepared by co-precipitation. The scanning electron microscopy and infrared spectroscopy showed that γ-PGA and Fe3O4 were successfully synthesized, and the magnetic particles showed good paramagnetism. The data shows that the adsorption capacity of regenerated γ-PGA/Fe3O4 to Pb2+ and Cd2+ can reach more than 70% of the first one. The comparison of FTIR spectra shows that the amount of COO- after reaction is greatly reduced, indicating that the -COOH in γ-PGA plays a major role in adsorption process. What's more, the natural resolution of adsorbent γ-PGA, γ-PGA/gelatin and γ-PGA/Fe3O4 were 11.3%, 0.7% and 0 respectively 24 hours after adsorption for Pb2+.