In the course of dark fermentative hydrogen production, a complex gaseous mixture with significant quantity of CO2 is formed. Hence, proper separation of H2 and CO2 is required for adequate utilization of hydrogen gas in fuel cell applications.
Technological solutions for the removal of CO2 can be designed by using gas separation membranes. Nevertheless, contemporary systems should be concerned with the consecutive valorization of carbon dioxide, as well. In this review article, the membrane-based technologies aiming at the effective separation of CO2 and biohydrogen (bioH2) will be evaluated, along with concise discussion and perspectives of integrative schemes offering alternatives for the biologically-mediated (fermentative, bioelectrochemical and algal) conversion of carbon dioxide into value-added substances, such as methane, hydrocarbons, etc.
With this analysis, the objective was to bring the most important aspects of membrane-assisted biohydrogen downstream technology under one cover and give insights to recent advancement and possible future research directions.