Key Laboratory for Water Quality and Conservation of Pearl River Delta, Guangdong Provincial Key Laboratory of Radionuclides Pollution Control and Resources, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China.
Key Laboratory for Water Quality and Conservation of Pearl River Delta, Guangdong Provincial Key Laboratory of Radionuclides Pollution Control and Resources, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China; Guangzhou University-Linköping University Research Center on Urban Sustainable Development, Guangzhou University, Guangzhou 510006, China.
Sci Total Environ. 2021 Jun 20;774:145733. doi: 10.1016/j.scitotenv.2021.145733. Epub 2021 Feb 8.
Bio-cathode Microbial electrolysis cell (MEC) is a promising and eco-friendly technology for concurrent hydrogen production and heavy metal reduction. However, the bioreduction of Antimony (Sb) in a bio-electrochemical system with H production is not explored. In this study, two efficient sulfate-reducing bacterial (SRB) strains were used to investigate the enhanced bioreduction of sulfate and Sb with H production in the MEC. SRB Bio-cathode MEC was developed from the microbial fuel cell (MFC) and operated with an applied voltage of 0.8 V. The performance of the SRB bio-cathode was confirmed by cyclic voltammetry, linear sweep voltammetry and electrochemical impedance spectroscopy. SRB strains of BY7 and SR10 supported the synergy reduction of sulfate and Sb by sulfide metal precipitation reaction. Hydrogen gas was the main product of SRB bio-cathode, with 86.9%, and 83.6% of H is produced by SR10 and BY7, respectively. Sb removal efficiency reached up to 88.2% in BY7 and 96.3% in SR10 with a sulfate reduction rate of 92.3 ± 2.6 and 98.4 ± 1.6 gmd in BY7 and SR10, respectively. The conversion efficiency of Sb (V) to Sb (III) reached up to 70.1% in BY7 and 89.2% in SR10. It was concluded that the total removal efficiency of Sb relies on the amount of sulfide concentration produced by the sulfate reduction reaction. The hydrogen production rate was increased up to 1.25 ± 0.06 (BY7) and 1.36 ± 0.02 m H/(m·d) (SR10) before addition of Sb and produced up to 0.893 ± 0.03 and 0.981 ± 0.02 mH/(m·d) after addition of Sb. The precipitates were characterized by X-ray diffraction and X-ray photoelectron spectroscopy, which confirmed Sb (V) was reduced to SbS.
生物阴极微生物电解池（MEC）是一种很有前途且环保的技术，可用于同时进行氢气生产和重金属还原。然而，在产氢的生物电化学系统中，锑（Sb）的生物还原尚未得到探索。在这项研究中，使用了两种高效的硫酸盐还原菌（SRB）菌株，以研究在 MEC 中利用 H 生产来增强硫酸盐和 Sb 的生物还原。SRB 生物阴极 MEC 是从微生物燃料电池（MFC）发展而来的，施加的电压为 0.8 V。通过循环伏安法、线性扫描伏安法和电化学阻抗谱对 SRB 生物阴极的性能进行了确认。菌株 BY7 和 SR10 支持通过硫化物金属沉淀反应协同还原硫酸盐和 Sb。氢气是 SRB 生物阴极的主要产物，分别由 SR10 和 BY7 产生 86.9%和 83.6%的 H。BY7 和 SR10 的 Sb 去除效率分别高达 88.2%和 96.3%，硫酸盐还原率分别为 92.3±2.6 和 98.4±1.6 gmd。BY7 和 SR10 中 Sb（V）到 Sb（III）的转化率分别高达 70.1%和 89.2%。结论是，Sb 的总去除效率取决于硫酸盐还原反应产生的硫化物浓度。在添加 Sb 之前，氢气产生率分别增加到 1.25±0.06（BY7）和 1.36±0.02 m H/（m·d）（SR10），添加 Sb 后，分别增加到 0.893±0.03 和 0.981±0.02 mH/（m·d）。通过 X 射线衍射和 X 射线光电子能谱对沉淀物进行了表征，证实 Sb（V）被还原为 SbS。
