Strategies for merging microbial fuel cell technologies in water desalination processes: Start-up protocol and desalination efficiency assessment

Microbial Desalination Cells constitute an innovative technology where microbial fuel cell and electrodialysis merge in the same device for obtaining fresh water from saline water with no energy-associated cost for the user. In this work, an anodic biofilm of the electroactive bacteria Geobacter sulfurreducens was able to efficiently convert the acetate present in synthetic waste water into electric current (j = 0.32 mA cm−2) able to desalinate water. .Moreover, we implemented an efficient start-up protocol where desalination up to 90% occurred in a desalination cycle (water production:0.308 L m−2 h−1, initial salinity: 9 mS cm−1, final salinity: <1 mS cm−1) using a filter press-based MDC prototype without any energy supply (excluding peristaltic pump energy). This start-up protocol is not only optimized for time but also simplifies operational procedures making it a more feasible strategy for future scaling-up of MDCs either as a single process or as a pre-treatment method combined with other well established desalination technologies such as reverse osmosis (RO) or reverse electrodialysis.