Mudher Israa, Ali Safaa A
Institute of Genetic Engineering and Biotechnology for Postgraduate Studies. University of Baghdad.
Cell Physiol Biochem. 2025 Mar 24;59(2):131-147. doi: 10.33594/000000767.
BACKGROUND/AIMS: Microbial desalination cells (MDCs) are bioelectrochemical systems using electroactive bacteria to generate energy simultaneously cleaning wastewater and desalinating water. This sustainable technology addresses pollution issues and water shortage using an environmentally friendly solution that aids in desalination as well as wastewater treatment. This research focuses on the effectiveness of microbial desalination cells (MDCs) in concurrently treating wastewater and removing salt from water. The study seeks to determine whether MDCs offer a viable, environmentally friendly method for purifying water while generating energy.
The MDC setup incorporated three distinct chambers: anode, desalination, and cathode. Wastewater samples were placed in the anode and cathode compartments, while the desalination chamber contained saline water. A digital multimeter was employed to regularly monitor and log the generated voltages. The microbial community was examined through 16S rRNA gene sequencing techniques. Organic matter elimination was quantified by measuring total organic carbon (TOC) levels. The MDC operated for 30 days continuously.
The microbial desalination cell (MDC) produced bioelectricity, effectively desalinated water, and broke down organic molecules during its 30-day running. This suggests that since the voltage generation peaked at 638 mV and then stabilized at 460 mV, the electrochemical activity has been constant. From 46.2 mS/cm to 10.1 mS/cm, the desalination chamber's electrical conductivity (EC) fell drastically, clearly removing the ions. A decline in sodium chloride (NaCl) concentration-from 29 mg/L to 7 mg/L-also proved a sign of effective desalination. Better organic degradation was shown by the cathode chamber reaching 99.9% while the anode chamber attained a total organic carbon (TOC) removal rate of 97.2%. Desalination mostly depends on selective ion exchange across cation and anion membranes; microbial biofilm adaptation helped in the slow development of voltage. These findings suggest that since they efficiently mix the processes of wastewater treatment, desalination, and power generation, MDCs are a reasonably sustainable technology. The Microbial Desalination Cell (MDC) effectively desalinated water and treated wastewater having a peak voltage of 638 mV and a drop in NaCl concentration from 29 mg/L to 7 mg/L. With TOC removal in the anode at 97.2% and the cathode at 99.9%, the system proved excellent in both desalination and organic matter degradation. Furthermore, found to be unique from NCBI-recognized species was the microbiome found in Iraqi municipal effluent.
Microbial Desalination Cells (MDCs) have many advantages over conventional desalination techniques like reverse osmosis, including being able to cleanse wastewater and simultaneously generate renewable electricity with far reduced energy usage. Constant challenges are improving ion exchange efficiency, honing interactions between microbial communities, and increasing technological scale. Improving MDC performance and incorporating it into whole energy and water management systems is the main emphasis of research nowadays. This could be a perfect choice for encouraging more environmentally friendly energy sources and lessening the consequences of world water shortage.
背景/目的：微生物脱盐电池（MDCs）是一种生物电化学系统，利用电活性细菌同时产生能量、净化废水和淡化海水。这项可持续技术通过一种既有助于海水淡化又有助于废水处理的环保解决方案，解决了污染问题和水资源短缺问题。本研究聚焦于微生物脱盐电池（MDCs）在同时处理废水和去除水中盐分方面的有效性。该研究旨在确定MDCs是否能提供一种可行的、环境友好的方法来净化水并产生能量。
MDC装置包含三个不同的腔室：阳极、脱盐和阴极。废水样本置于阳极和阴极隔室中，而脱盐室装有盐水。使用数字万用表定期监测并记录产生的电压。通过16S rRNA基因测序技术检测微生物群落。通过测量总有机碳（TOC）水平来量化有机物的去除情况。MDC连续运行30天。
微生物脱盐电池（MDC）在其30天的运行过程中产生了生物电，有效淡化了海水，并分解了有机分子。这表明，由于电压产生在638 mV时达到峰值，然后稳定在460 mV，电化学活性一直保持恒定。脱盐室的电导率（EC）从46.2 mS/cm急剧下降到10.1 mS/cm，明显去除了离子。氯化钠（NaCl）浓度从29 mg/L降至7 mg/L也证明了有效脱盐。阴极室达到99.9%，阳极室总有机碳（TOC）去除率达到97.2%，表明有机降解效果更好。脱盐主要依赖于阳离子和阴离子膜之间的选择性离子交换；微生物生物膜的适应性有助于电压的缓慢形成。这些发现表明，由于MDCs有效地整合了废水处理、海水淡化和发电过程，它们是一种相当可持续的技术。微生物脱盐电池（MDC）有效淡化了海水并处理了废水，峰值电压为638 mV，NaCl浓度从29 mg/L降至7 mg/L。阳极TOC去除率为97.2%，阴极TOC去除率为99.9%，该系统在脱盐和有机物降解方面均表现出色。此外，在伊拉克城市污水中发现的微生物群落与美国国立医学图书馆（NCBI）认可的物种不同。
与反渗透等传统脱盐技术相比，微生物脱盐电池（MDCs）具有许多优势，包括能够净化废水并同时产生可再生电力，且能源消耗大幅降低。持续面临的挑战包括提高离子交换效率、优化微生物群落之间的相互作用以及扩大技术规模。提高MDC性能并将其纳入整个能源和水管理系统是当今研究的主要重点。这可能是鼓励使用更环保能源和减轻全球水资源短缺影响的理想选择。
