Environmental Technology, Wageningen University, P.O. Box 17, Wageningen, The Netherlands; Paqell B.V., Reactorweg 301, 3542 AD Utrecht, The Netherlands.
Environmental Technology, Wageningen University, P.O. Box 17, Wageningen, The Netherlands.
J Hazard Mater. 2022 Feb 15;424(Pt A):127358. doi: 10.1016/j.jhazmat.2021.127358. Epub 2021 Sep 26.
Sulfide oxidizing bacteria (SOB) are widely applied in industry to convert toxic HS into elemental sulfur. Haloalkaliphilic planktonic SOB can remove sulfide from solution under anaerobic conditions (SOB are 'charged'), and release electrons at an electrode (discharge of SOB). The effect of this electron shuttling on product formation and biomass growth is not known. Here, we study and demonstrate a continuous process in which SOB remove sulfide from solution in an anaerobic 'uptake chamber', and shuttle these electrons to the anode of an electrochemical cell, in the absence of dissolved sulfide. Two experiments over 31 and 41 days were performed. At a sulfide loading rate of 1.1 mmolS/day, electricity was produced continuously (3 A/m) without dissolved sulfide in the anolyte. The main end product was sulfate (56% in experiment 1% and 78% in experiment 2), and 87% and 77% of the electrons in sulfide were recovered as electricity. It was found that the current density was dependent on the sulfide loading rate and not on the anode potential. Biological growth occurred, mainly at the anode as biofilm, in which the deltaproteobacterial genus Desulfurivibrio was dominating. Our results demonstrate a novel strategy to produce electricity from sulfide in an electrochemical system.
硫氧化细菌（SOB）广泛应用于工业领域，用于将有毒的 HS 转化为元素硫。嗜盐浮游硫氧化细菌可以在厌氧条件下（SOB 被“充电”）从溶液中去除硫化物，并在电极上释放电子（SOB 放电）。这种电子穿梭对产物形成和生物量生长的影响尚不清楚。在这里，我们研究并展示了一个连续的过程，即在没有溶解的硫化物的情况下，SOB 从溶液中去除硫化物，并将这些电子输送到电化学电池的阳极。进行了两个为期 31 天和 41 天的实验。在 1.1 mmolS/天的硫化物负荷率下，在没有溶解的硫化物的情况下，连续产生电流（3 A/m）。主要的最终产物是硫酸盐（实验 1 为 56%，实验 2 为 78%），硫化物中的 87%和 77%的电子以电能的形式回收。结果发现，电流密度取决于硫化物的负荷率，而不是阳极电位。生物生长发生了，主要是在阳极作为生物膜，其中δ变形菌属的脱硫菌属占主导地位。我们的结果证明了在电化学系统中从硫化物中产生电能的一种新策略。
