Characteristics of copper removal and ion release during copper biosorption by Stenotrophomonas maltophilia in presence of benzo[a]pyrene

TIAN Yun(田云)¹, YE Jin-shao(叶锦韶)¹, YIN Hua(尹华)², PENG Hui(彭辉)¹, LI Qu-sheng(李取生)¹, BAI Jie-qiong(白洁琼)¹, XIE Dan-ping(谢丹平)³

(1. Department of Environmental Engineering, Key Laboratory of Water/Soil Toxic Pollutants Control and Bioremediation of Guangdong Higher Education Institutes, Jinan University, Guangzhou 510632, China;
2. College of Environment and Energy, Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters of Ministry of Education, South China University of Technology, Guangzhou 510006, China;
3. Key Lab of Water and Air Pollution Control of Guangdong Province, Guangzhou 510655, China)

Abstract:The ability of Stenotrophomonas maltophilia was demonstrated to selectively remove Cu²⁺ from Cu(NO₃)₂ solution under the circumstance that 1 mg/L benzo[a]pyrene (BaP) was either present or not. The removal ratios of 2 and 10 mg/L Cu²⁺ by 0.25 g/L biosorbent are up to 80% and 49% at 10 min, respectively. The biosorption includes ion exchange, NO₃^- reduction, ion release, and cell oxidation by Cu²⁺. BaP does not significantly affect Cu²⁺ removal and ion release. Although 2 mg/L Cu²⁺ increases the release of PO₄^3-, K⁺, NH₄⁺ and Ca²⁺, 10 mg/L Cu²⁺ has strong oxidation on cell, and then decreases NO₃^- reduction and hinders the release of K⁺, NH₄⁺ and Ca²⁺. Exogenous cations inhibit the Cu²⁺ biosorption, while additional anions increase the removal ratios of 10 mg/L Cu²⁺ from 52% to 88%.

Key words:biosorption; copper; benzo[a]pyrene; Stenotrophomonas maltophilia