Experimental investigation of anion exchange membrane water electrolysis for a tubular microbial electrosynthesis cell design

Tubular water splitting electrolyzer was adapted to neutral pH conditions for the in-situ H2 supplying microbial electrosynthesis design. The electrolyzer was optimized to reduce ohmic losses and provide adequate gas separation. Direct membrane deposition was applied on a thin anionic exchange membrane for the membrane-electrode-assembly fabrication. Although the membrane resistance increased with the increasing membrane thickness from 55 to 165 μm, the contact resistance was reduced by applying stronger compression pressure on the membrane-electrode interface. A durability test was run for 120 h, showing a voltage increase of 134 μV/h. Moreover, the hydrogen permeability coefficient was determined at 10−14 mol/(mˑsˑPa).