Converting CO 2 from a Harmful Gas to a Renewable Source of Matter and Energy: A Review

Abstract

The emission of greenhouse gases, specifically CO 2, has reached non-acceptable levels causing global warming with adverse effects. Owing to rigorous ongoing research, these harmful substances might be converted to beneficial sources. The main objective of this study was to review the most effective processes that might utilize carbon dioxide to produce various substances, chemicals, and energy. For this, different existing and projected short-term and long-term strategies have been presented and discussed. Specifically, processes like the artificial tree of Lackner to capture CO 2, chemical looping combustion (CLC), the application of CO 2 in the food and processing industry, wastewater treatment, supercritical and refrigerant CO 2, hydrogenation of CO 2, the cultivation of microalgae, thermolysis, electrolysis, and photoelectrocatalysis techniques for producing hydrogen and biofuels, based on thermochemical processes, are the most promising ways to reduce and reuse CO 2. Such behavioral changes can lead to the exchange of CO 2 between natural reservoirs and help to maintain CO 2 equilibrium among the atmosphere, the upper mixed layer of the sea, and the deep sea. Consequently, the mean global temperature and the climate are directly affected.