锐钛矿光电子强化黑曲霉吸附铅离子实验研究

摘要

Lead is widely distributed in nature,and its soluble salts have great toxicity to animals,plants and human bodies.The removal of lead pollution in the environment by biological remediation such as fungi has becomes one of the hot topics.In this paper,the anatase electrode was synthesized using sol-gel method,and characterized by X ray diffraction (XRD),the Rarnan,environmental scanning electron microscopy (ESEM) and electrochemical testing.The light-semiconductor mineral-microbial system was successfully constructed with anatase electrode and Aspergillus niger Bpb1.The effect of photoelectron on adsorption of lead ions by Aspergillus niger was studied.The experimental results showed that the adsorption rate of the experimental group increased by 33.6 ％ on average with the highest being 42 ％ compared with the control group.The photoelectron did not affect the morphology of lead minerals.Combined with energy spectrum test and previous literature,the authors found that lead ions were combined with organic acids to form minerals with organic lead salts,which were twined in hyphae.In this study,the anatase photoelectron could enhance the adsorption rate of lead ion by fungi,but did not affect its morphology.%铅元素在自然界分布广泛,其可溶性盐对动植物及人体有巨大毒性,借助真菌等生物修复技术手段清除环境中铅污染逐渐成为研究热点之一.本文使用溶胶凝胶法合成了锐钛矿电极,通过X射线衍射(XRD)、拉曼测试、环境扫描电镜和电化学测试等对其进行了系统表征,进而联合实验室分离筛选出的一株黑曲霉Aspergillus nigerBpb1成功构建了光-半导体矿物-微生物系统.研究了光电子对黑曲霉吸附铅离子的影响,实验结果表明锐钛矿光电子与黑曲霉协同作用下,实验组较对照组铅离子吸附速率平均增加33.6％,最高增加42％.进一步使用环境扫描电镜观察黑曲霉外部形态,发现光电子不影响铅矿物的形态.结合能谱测试和前人文献得知铅离子与有机酸结合形成以有机铅盐为主的矿物,缠绕在菌丝中.本研究实现了利用光能加速真菌代谢的过程,表明锐钛矿光电子与黑曲霉协同作用只对真菌吸附铅离子速率产生一定的加强,并未影响其成矿形态.