chemical-looping, process development, hydrothermal processes, sustainability, feasibility
Chemical-looping technology for capturing CO2 are discussed with critical assessments of the circulating fluidized bed systems and the packed bed reactor with periodic switching of the feed streams of fuel and air. Beside, some industrial chemical processes, we have developed, for converting CO2 into value added chemicals are discussed. The first process uses 137.31 tonne/day CO2 and hydrogen to produce 100.0 tonne/day of methanol. Electrolysis of water using the electricity from wind power supplies the hydrogen and helps store the electricity in the form of methanol. The second process is the production of propylene carbonate (200,226,816 lb/year) and polypropylene carbonate (200 million lb/year) from propylene oxide and CO2 by using 9990.2 lb/hr and 12762.8 lb/hr CO2, respectively. Another process uses 1652.97 kg/hr of bioglycerol and 273.74 kg/hr of CO2 to produces 670.9 kg/hr bioglycerol carbonate by direct carboxylation. CO2 can also be converted to formic acid, methanol, and hydrogen by using zero-valent metal/metal oxide redox cycles under hydrothermal conditions. The oxidized metal can be regenerated by glycerin, which is converted to lactic acid. These case studies emphasize the sustainability and feasibility and illustrate some clean chemical process technologies and positive impact of converting CO2 to useful chemicals on global warming.