Department of Chemistry, University of Science & Technology of China, Hefei 230026, China.
Department of Chemistry, University of Science & Technology of China, Hefei 230026, China.
Bioresour Technol. 2014 May;160:15-23. doi: 10.1016/j.biortech.2013.11.074. Epub 2013 Dec 1.
Biosorption presents a potent technology to remediate metal-contaminated aqueous environment or even to recover precious metals. Extracellular polymeric substances (EPS) are believed to play an important role in metal biosorption by microorganisms, but the reported results have been rather contradictory and the underlying mechanisms remain largely unclear so far. This review aims to clarify why large discrepancies existed for different EPS-metal systems through systematically exploring into the adsorption mechanisms and influential factors, and to offer some implications for advancing the implementation of metal biosorption technologies. The state-of-the-art methodologies for characterizing metal-EPS binding are summarized; several interaction mechanisms, including ion exchange, complexation and surface precipitation, are analyzed; the major influential factors such as EPS composition, metal species, solution chemistry and operating conditions are discussed; and lastly future research needs to advance the investigations and implementations of such biosorption processes are proposed.
生物吸附是一种有效的技术，可以修复受金属污染的水生态环境，甚至可以回收贵金属。细胞外聚合物（EPS）被认为在微生物对金属的吸附过程中发挥着重要作用，但目前为止，相关报道结果却大相径庭，其潜在机制仍不清楚。本综述旨在通过系统地探讨吸附机制和影响因素，阐明为什么不同的 EPS-金属体系会存在较大差异，并为推进金属生物吸附技术的应用提供一些启示。本文总结了目前用于表征金属-EPS 结合的先进方法学，分析了几种相互作用机制，包括离子交换、络合和表面沉淀，讨论了 EPS 组成、金属种类、溶液化学和操作条件等主要影响因素，并提出了未来研究的需要，以推进对这些生物吸附过程的研究和应用。
