GENOCOV, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
GENOCOV, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
Water Res. 2017 Oct 15;123:301-310. doi: 10.1016/j.watres.2017.06.050. Epub 2017 Jun 20.
Bioelectrochemical systems (BESs) are being studied as an alternative technology for the treatment of several kinds of wastewaters with a lack of electron donor such as high-strength sulfate wastewaters. This study evaluates different parameters that influence the simultaneous sulfate reduction and sulfide oxidation in an autotrophic biocathode: ion-exchange membrane (IEM), cathodic pH and cathode potential. Two different membranes were studied to evaluate sulfate and sulfide adsorption and diffusion from the cathode to the anode, observing that a cation-exchange membrane (CEM) widely decreased these effects. Three different cathode pH (5.5, 7 and 8.5) were studied in a long-term operation observing that pH = 7 was the optimal for sulfate removal, achieving reduction rates around 150 mg S-SO L d. Microbial community analysis of the cathode biofilm demonstrated a high abundance of sulfate-reducing bacteria (SRB, 67% at pH 7, 60% at pH 8.5 and 42% at pH 5.5), mainly Desulfovibrio sp. at pH 5.5 and 7 and Desulfonatronum sp. at pH 8.5. The cathode potential also was studied from -0.7 to -1.2 V vs. SHE achieving sulfate removal rates higher than 700 mg S-SO L d at cathode potentials from -1.0 to -1.2 V vs. SHE. Also, the highest cathodic recovery and the highest sulfur species imbalance were observed at a cathode potential of -1.0 V vs. SHE, which indicated a higher elemental sulfur production.
生物电化学系统（BESs）作为一种替代技术，正在被研究用于处理多种缺乏电子供体的废水，如高强度硫酸盐废水。本研究评估了影响自养生物阴极中硫酸盐还原和硫化物氧化同时进行的几个参数：离子交换膜（IEM）、阴极 pH 值和阴极电位。研究了两种不同的膜，以评估从阴极到阳极的硫酸盐和硫化物的吸附和扩散，结果表明阳离子交换膜（CEM）广泛降低了这些影响。在长期运行中研究了三种不同的阴极 pH 值（5.5、7 和 8.5），结果表明 pH = 7 是硫酸盐去除的最佳条件，可达到约 150 mg S-SO₅²⁻ L d 的还原速率。阴极生物膜的微生物群落分析表明，硫酸盐还原菌（SRB）的丰度很高（pH 7 时为 67%，pH 8.5 时为 60%，pH 5.5 时为 42%），主要为 Desulfovibrio sp.，在 pH 5.5 和 7 时为 Desulfonatronum sp.，在 pH 8.5 时为 Desulfonatronum sp.。还研究了从 -0.7 到 -1.2 V vs. SHE 的阴极电位，结果表明在 -1.0 到 -1.2 V vs. SHE 的阴极电位下，硫酸盐去除率高于 700 mg S-SO₅²⁻ L d。此外，在 -1.0 V vs. SHE 的阴极电位下观察到最高的阴极回收率和最高的硫物种失衡，这表明元素硫的产量更高。
