Rice husk-modified ceramic membrane for microbial desalination cell

Ceramic membranes have beenx utilized for long as an inexpensive ion exchange membrane in microbial desalination cells (MDC). This work focuses on producing inexpensive ceramic membranes combining rice husk and soil for use in MDC. A ceramic membrane comprising 30% rice husk demonstrated enhanced ion exchange capacity. The presence of silica in rice husk improved the membrane’s hydration characteristics and ion mobility across the chamber by 20%. The performance of the membranes with modified rice husk (MDC 1), and unmodified without rice husk (MDC 2) for the treatment of reverse osmosis reject water was investigated. The maximum power densities were 112 ± 5 mW/m² and 82 ± 8 mW/m², and COD removal efficiencies were 80.7 ± 2% and 66 ± 1.8% for MDC 1 and MDC 2, respectively. The rice husk composite membrane had an ion exchange capacity of 0.097 mmol H⁺/g and 0.095 mmol H⁺/g, while it was 0.076 mmol H⁺/g and 0.060 mmol H⁺/g for unmodified membrane before and after 30 days of operation, respectively. This suggests that the addition of rice husk increased the hydrophilicity of the membrane and pore walls and demonstrate better ion exchange capacity. Thus, the rice husk composite membrane had a lower incidence of fouling which makes it more suitable for prolonged usage. This work demonstrates that the rice husk membrane could be a viable alternative to the costly membranes in MDC with improved power performance.