Carbon Dioxide Separation from Flue Gases: A Technological Review Emphasizing Reduction in Greenhouse Gas Emissions

Increasing concentrations of greenhouse gases (GHGs) such as CO2 in the atmosphere is a global warming. Human activities are a major cause of increased CO2 concentration in atmosphere, as in recent decade, two-third of greenhouse effect was caused by human activities. Carbon capture and storage (CCS) is a major strategy that can be used to reduce GHGs emission. There are three methods for CCS: pre-combustion capture, oxy-fuel process, and post-combustion capture. Among them, post-combustion capture is the most important one because it offers flexibility and it can be easily added to the operational units. Various technologies are used for CO2 capture, some of them include: absorption, adsorption, cryogenic distillation, and membrane separation. In this paper, various technologies for post-combustion are compared and the best condition for using each technology is identified

Activated-carbon nanofibers/graphene nanocomposites and their adsorption performance towards carbon dioxide

Activated-carbon nanofibers (ACNFs) provide a relatively new, modified structure of carbon-based adsorbents that have the ability to adsorb carbon dioxide due to their high specific surface area, wide distribution of porous structures, and high volume of active sites. In this study, cost-effective agricultural waste-based graphene synthesized from rice husk ashes was used as additive to enhance the ACNF properties. ACNF/graphene (gACNF) is still a relatively unexplored adsorbent. The resultant gACNF exhibited better thermal stability properties, with higher yield, larger specific surface area, and higher micropore volume. These properties are the main factors contributing to their enhanced adsorption performance towards CO2