Investigation on the performance of microbial capacity desalination cell

The effects of desalination time, concentration of salt water and the number of capacity electrode on the performance of salt removal were investigated in a microbial capacity desalination cell (MCDC). The MCDC was constructed by inserting a cation exchange membrane (CEM) next to the anode and an anion exchange membrane (AEM) next to the cathode. Results showed that the conductivity of salt water decreased at the beginning of time and then increased slowly, when treating 5 g·L^-1 of NaCl solution. When the reactor operated for 30 min with 5 g·L^-1 NaCl solution, the salt removal efficiency reached the highest of 47.83%. The conductivity reductions of anolyte and catholyte in MCDC were 15.24% and 6.12% respectively after desalinated for 150 min. With the increase of NaCl concentration, the salt removal efficiency decreased and the adsorption quantity of total dissolved solid per gram activated carbon cloth increased. According to the equation liner fittings of the Langmuir and Freundlich, the maximum adsorption capacity of MCDC was 72.99 mg·g^-1 and the capacity adsorption was complex bilayer adsorption. The salt removal efficiency increased by 37.37%, when the electrode number increased from 1 to 4 pairs. The capacity can be regenerated within 1 h through exchange the connection of electrode and activated carbon cloth assemblies.