Enhanced biosorption of Cr(VI) from synthetic wastewater using algal-bacterial aerobic granular sludge: Batch experiments, kinetics and mechanisms
Enhanced biosorption of Cr(VI) from synthetic wastewater using algal-bacterial aerobic granular sludge: Batch experiments, kinetics and mechanisms
复制标题
DOI：
10.1016/j.seppur.2020.117323
复制
发表时间：
2020-11
影响因子：
8.6
通讯作者：
Xiaojing Yang;Ziwen Zhao;Yang Yu;K. Shimizu;Zhenya Zhang;Z. Lei;Duu-Jong Lee
中科院分区：
文献类型：
--
作者：
Xiaojing Yang;Ziwen Zhao;Yang Yu;K. Shimizu;Zhenya Zhang;Z. Lei;Duu-Jong Lee
生物吸附法是一种经济高效、环境友好的废水中Cr（VI）去除工艺。本研究是第一次报告藻类细菌好氧颗粒污泥（AGS）被用作生物吸附剂去除铬（VI）相比，传统的细菌AGS方面的生物吸附性能。批测试表明，藻菌AGS对Cr（VI）的生物吸附高度依赖于pH值，最大Cr（VI）生物吸附容量为51.0 mg g-1，发生在pH 2时。藻-菌AGS对Cr（VI）的去除是通过生物吸附和生物还原两种反应完成的，其中涉及静电相互作用、离子交换、表面络合和生物还原4种机理。脱附实验表明，NaHCO_3可回收藻-菌AGS吸附Cr的64-73%，且大部分吸附Cr以Cr（III）的形式存在。与传统的细菌AGS相比，藻-菌AGS表现出更高的吸附能力和更好的颗粒稳定性，这意味着藻-菌AGS更有潜力作为Cr（VI）去除和回收生物材料用于含Cr（VI）废水的处理。
Biosorption is considered as a cost-effective and environmentally friendly Cr(VI) removal process from wastewater. This study is the first report on algal-bacterial aerobic granular sludge (AGS) being used as biosorbent for Cr(VI) removal in comparison to conventional bacterial AGS with respect to biosorption performance. Batch tests revealed that Cr(VI) biosorption onto algal-bacterial AGS was highly pH dependent and the maximum Cr(VI) biosorption capacity of 51.0 mg g−1occurred at pH 2. The Cr(VI) removal by algal-bacterial AGS was found to be accomplished by both biosorption and bioreduction reactions, in which four mechanisms, namely electrostatic interactions, ion exchange, surface complexation and bioreduction were involved. In addition, desorption tests showed that 64–73% of the adsorbed Cr onto the algal-bacterial AGS could be recovered by NaHCO3, and most of the adsorbed Cr was in the form of Cr(III). Compared to the conventional bacterial AGS, algal-bacterial AGS demonstrated higher biosorption capacity and better granular stability, implying that algal-bacterial AGS can be more potentially utilized as a Cr(VI) removal and recovery biomaterial for the treatment of Cr(VI)-containing wastewater.