A review of carbon dioxide capture and utilization by membrane integrated microalgal cultivation processes

The capture of carbon dioxide (CO₂) from the air for microalgal cultivation has received increasing interest since it allows advantages that do not only reduce the amount of CO₂ already added to the air, but it is also more economical due to the accessibility of air, there are no regeneration requirements and it is a safe method that can help enhance microalgal growth. In order to capture CO₂ from the air, it is necessary to deal with CO₂ emissions from all sources in an atmosphere. Interestingly, the capture unit and microalgal culture can be located at any favorable site. Although a number of photobioreactors have been proposed with a CO₂ distribution system, the consequence of CO₂ losses is still being ignored. Thus, capturing CO₂ from the air via an integrated separation process in a photobioreactor is required for microalgal cultivation. Among the four available separation technologies, the membrane separation process would offer a safe, reliable and low cost method for CO₂ capture. Thus, this method of separation can be considered as a key factor in accelerating the development of a CO₂ enrichment process from the air for microalgal cultivation.