Spectroscopic Characterization of Heavy Metal Wastewater Treatment by Pyrite
ZHANG Ping1,2,LIANG Min-hua1,CHEN Yong-heng2*
1. Institute of Guangzhou Development Research, Guangzhou University, Guangzhou 510006, China 2. Key Laboratory of Pollution Control and Isotope Application Technology, Guangzhou University, Guangzhou 510006, China
Abstract:Treatment of acidic heavy metal wastewater by pyrite was studied by reflectance spectroscopy and absorption spectroscopy. The surface reaction in pyrite and the interaction between pyrite and heavy metal were investigated. The diffuse reflectance FTIR spectroscopy(DRIFTS) showed that the surface hydroxyls in pyrite reacted with heavy metal ion in the process of wastewater treatment, and furthermore, the phenomenon of the acidic wastewater driven to neutrality(pH 7) naturally after treatment was reasonably explained by analyzed carbonate in pyrite. The reflectance spectroscopy in visible region can be used to characterize the change of mineral particle and specific surface in this treatment process, and the reasons for the activity of pyrite increasing in repetitive use were explained. A process of adsorption-precipitation from Cr(Ⅵ) to Cr3+ and to Cr(OH)3 was proved by absorption spectroscopy and XPS during the treatment of Cr(Ⅵ)-bearing wastewater by pyrite.
[1] Brown J R, Bancroft G M,et al. Environ. Sci. Technol., 1979, 13 (6) : 1142. [2] Jean G E, Bancroft GM. Geochim. Cosmochim. Acta, 1986, 50(7): 1455. [3] Hyland M M, Jeam G E, Bancroft G M. Geochim. Cosmochim. Acta, 1990, 54(7): 1957. [4] SHI Jun-xian, LU An-huai, LU Xiao-ying(石俊仙, 鲁安怀, 卢晓英). Bulletin of Mineralogy, Petrology and Geochemistr(矿物岩石地球化学通报). 1999, 18(4): 226. [5] JIA Jian-ye, PAN Zhao-lu, XIE Xian-de(贾建业, 潘兆橹, 谢先德). Acta Petrologica et Mineralogica(岩石矿物学杂志),1999, 18(4): 316. [6] ZHANG Ping, CHEN Yong-heng, YAO Yan(张 平,陈永亨, 姚 焱). Spectroscopy and Spectral Analysis(光谱学与光谱分析),2006,26(5):971. [7] ZHANG Ping, CHEN Yong-heng(张 平,陈永亨). Treatment Method of Heavy Metal Wastewater(含重金属废水的处理方法). Chinese Patent(中国专利), 200510035580.9. [8] PENG Wen-shi, LIU Gao-kui(彭文世, 刘高魁). Chart Integration of Infrared Spectra of Minerals(矿物红外光谱图集). Beijing: Science Press(北京: 科学出版社),1982. 76, 141. [9] WU Jin-guang(吴瑾光). Technology and Application of Modern FTIR Spectroscopy(近代傅里叶变换红外光谱技术及应用·下卷). Beijing: Science and Technology Literature Press(北京: 科技文献出版社),1994. 256. [10] Davis J A, Kent D B. In: Hochella Jr M F , White A F ed. Mineral-Water Interface Geochemistry. Washington DC MSA Publication Limited, 1990. 177.