It is important to recover precious metals from secondary wastewater because of their low crustal abundance. The selective adsorption of palladium (Pd) and platinum (Pt) ions from secondary wastewater, which contains a large amount aluminium and sodium ions, was investigated using Escherichia coli BL21 (BL21), genetically modified E. coli BL21 (EC20) and Providencia vermicola (P. V.). The results demonstrated that P.V., BL21 and EC20 cells took 95.9%, 88.2% and 97.5% of Pd ions, and 64.8%, 93.2% and 100% of Pt ions form industrial wastewater, respectively. All three bacterial biomass could be reused for Pd adsorption with a second adsorption efficiency of > 85%, specifically, the EC20 cells could absorb 93.8% of Pd ions from wastewater. SEM-EDS and XPS analyses confirmed the occurrence of Pd and Pt on the surface of wastewater-absorbed biomass. The shift in FTIR spectrum implied that functional groups, such as hydroxyl, amino, carboxyl and phosphate groups, were involved in wastewater adsorption.

中文翻译：

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使用大肠杆菌BL21和Providencia vermicola从二级废水中选择性吸附钯和铂。

由于地壳含量低，从二次废水中回收贵金属非常重要。使用大肠杆菌BL21（BL21），基因修饰的大肠杆菌BL21（EC20）和Providencia vermicola研究了次级废水中含有大量铝和钠离子的钯（Pd）和铂（Pt）离子的选择性吸附（PV）。结果表明，PV，BL21和EC20电池分别占工业废水中Pd离子的95.9％，88.2％和97.5％，以及Pt离子分别占64.8％，93.2％和100％。这三种细菌生物量都可以再用于Pd吸附，其第二吸附效率> 85％，特别是EC20细胞可以吸收废水中93.8％的Pd离子。SEM-EDS和XPS分析证实了废水吸收生物质表面上存在Pd和Pt。