地质学报（英文版）2006，Vol.80Issue(4)：597-603,7.
A Study of Chromium Adsorption on Natural Goethite Biomineralized with Iron Bacteria
A Study of Chromium Adsorption on Natural Goethite Biomineralized with Iron Bacteria
摘要
Abstract
Goethite, especially biogenic goethite, has high specific surface area and great capacity for the adsorption of many contaminants including metal ions and organic chelates. Chromium is a redox actively toxic metal ion that exists as either CrⅢ or CrⅥ in nature, and as such it is essential to understand its behavior of adsorption on natural goethite mineralized by iron bacteria, as Gallionella and Leptothrix in water body. The adsorption of Cr3+ and CrⅥ on naturally biomineralized goethite is studied in this paper. The results show that both Langmuir and Freundlich adsorption isothermal models are able to accurately describe the adsorption of these two ions. Investigation of SEM/EDS,TEM/EDS indicates that the two ions do not adsorb homogeneously on goethite owing to the different microstructures of goethite, and that the microspherical goethite has a greater adsorption capacity for chromium ions than the helical one. XPS data show that redox reaction of chromium on the surface of biomineralized goethite takes place in the adsorption of both Cr3+ and CrⅥ. The CrⅥ adsorbed on biogoethite is much easier to transform into CrⅢ than the oxidization of CrⅢ on the bio-goethite.关键词
biomineralized goethite/adsorption/chromium/iron bacteriaKey words
biomineralized goethite/adsorption/chromium/iron bacteria分类
天文与地球科学引用本文复制引用
SUN Zhenya,ZHU Chunshui,HUANG Jiangbo,GONG Wenqi,CHEN Hesheng,MU Shanbin..A Study of Chromium Adsorption on Natural Goethite Biomineralized with Iron Bacteria[J].地质学报（英文版）,2006,80(4):597-603,7.基金项目
This project is supported by grants from the National Natural Science Foundation of China (Grant Nos.40072015 and 40372028) and the National "973" Plan Project (Grant No. 2004CB619204). （Grant Nos.40072015 and 40372028）
