摘要
The effects of photogenerated-hole scavengers(ascorbic acid,oxalic acid,humic acid and citric acid)on chalcopyrite bioleaching in the presence of visible light were studied using Acidithiobacillus ferrooxidans(A.ferrooxidans).Four sets of bioleaching experiments were performed:(1)visible light+0 g/L scavenger,(2)visible light+0.1 g/L of different scavenger(ascorbic acid,oxalic acid,humic acid and citric acid),(3)dark+0.1 g/L of different scavenger(ascorbic acid,oxalic acid,humic acid and citric acid),and(4)dark+0 g/L scavenger(control group).The results showed that ascorbic acid and oxalic acid could act as photogenerated-hole scavengers and significantly enhance chalcopyrite bioleaching under visible light.The dissolved copper in the light group without scavenger was only 18.7%higher than that of the control group.The copper extraction rates of the light groups with oxalic acid and ascorbic acid were respectively 30.1%and 32.5%higher than those of the control group.Scanning electron microscopy(SEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FT-IR)analyses indicated that ascorbic acid and oxalic acid as photogenerated-hole scavenger could capture photo-generated holes and inhibit jarosite formation on the chalcopyrite surface,thereby enhancing bioleaching of chalcopyrite under visible light.
通过嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)研究光生空穴清除剂(抗坏血酸、草酸、腐质酸和柠檬酸)对光催化黄铜矿生物浸出的影响。设置4组生物浸出实验:(1)可见光+0 g/L光生空穴清除剂;(2)可见光+0.1 g/L不同光生空穴清除剂(抗坏血酸、草酸、腐植酸和柠檬酸);(3)黑暗+0.1 g/L不同光生空穴清除剂(抗坏血酸、草酸、腐植酸和柠檬酸);(4)黑暗+0 g/L光生空穴清除剂(对照组)。结果表明,光照条件下,抗坏血酸和草酸作为光生空穴清除剂时,能够显著促进黄铜矿生物浸出。可见光+0 g/L光生空穴清除剂组的铜离子溶出率比对照组高18.7%;可见光+0.1 g/L草酸组和可见光+0.1 g/L抗坏血酸组的黄铜矿溶出率分别比对照组高30.1%和32.5%。SEM,XRD和FT-IR分析表明,抗坏血酸和草酸作为光生空穴清除剂能够捕获光生空穴和抑制黄钾铁矾在黄铜矿表面形成,从而促进光催化黄铜矿的生物浸出。
基金
Project(41773089)supported by the National Natural Science Foundation of China
Project(2017SK2255)supported by the Key R&D Program of Hunan Province,China
Project(2015CNERC-CTHMP-05)supported by the Opening Foundation of the Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution,China
Project(CX20190136)supported by the Hunan Provincial Innovation Foundation for Postgraduates,China
Project(CSUZC201808)supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,China.
作者简介
Corresponding author:Jian-yu ZHU,Min GAN,Tel:+86-13755146512,E-mail:zhujy@csu.edu.cn,ganmin0803@sina.com
