Advanced biological and non-biological technologies for carbon sequestration, wastewater treatment, and concurrent valuable recovery: A review

Over the last few years, mitigation of global warming has become a challenge for researchers. Therefore, CO2 conversion into energy-rich valuables and fuels can become a crucial strategy for abating the growing global CO2 emission. However, the CO2 molecule is highly stable, which requires large over potential for converting it to valuable chemicals; thus, making its reduction quite difficult. In this regard, technologies, such as microbial electrochemical technology (MET), photocatalytic and electrochemical technologies triggered considerable interest in the reduction of CO2. These technologies can help in solving the global climate issue based on mitigating the CO2 into the desired product like formic acid, methanol, methane, and other valuables with low energy consumption and minimal carbon emission. Thus, the objective of this review is to provide an updated critical discussion on the recent progress in application of biological and non-biological technologies for CO2 reduction and wastewater treatment. Moreover, the mechanism governing the microbial, photocatalytic, and electrocatalytic CO2 reduction and pollutant removal from wastewater along with a detailed discussion of catalysts used in these technologies are also highlighted. Further, brief prospective and future recommendations on the development of efficient CO2 reduction technologies have also been elucidated in this article, which could be vital for enhancing the conversion efficiency of CO2 in the reduction system.