LAUSR

Abstract Water and energy shortages are considered to be very serious global issue. As a consequence, it is necessary to develop an alternative water resource such as desalination and wastewater treatment etc. Microbial desalination cell (MDC) is the new, green and environment–friendly technology that desalinates seawater and produces bioelectricity. This study integrate desalination with wastewater treatment and bioelectricity production in MDC by utilizing microalgae as bio-cathode and the results were compared with the chemical cathode. Recently, microalgae have received a high attention for application in bio-electrochemical systems due to its potential to be used for oxygen generation and biodiesel production. The study utilizes petroleum wastewater in the anode chamber and microalgae Scenedesmus abundans in the cathode chamber. The results have highlighted that microalgae bio-cathodes perform better than chemical cathode and increases COD removal and produce a considerable amount of bioelectricity. It also proved that high initial salt concentration 35 g Nacl L −1 desalinates well when compared with low initial salt concentration 20 g NaCl L −1 .The maximum voltage and desalination efficiency of MDC 1 (35 g NaCl L −1 ) and MDC 2(20 g NaCl L −1 ) is found to be 654 mv and 55.3%; 506 mv and 42.6% with the volumetric ratio of 1:0.5:1(anode, desalination chamber and microalgae cathode). Thus the experimental results reveal that utilizing bio-cathode MDC proved to be a promising platform for effective desalination of sea water.