Use of nanoparticles Cu/TiO(OH)2 for CO2 removal with K2CO3/KHCO3 based solution: enhanced thermal conductivity and reaction kinetics enhancing the CO2 sorption/desorption performance of K2CO3/KHCO3

Global climate change resulting from substantial CO2 emissions is increasingly attracting attention, and coal‐fired power plants are a major source of CO2 emission, so it is necessary to control and reduce CO2 emissions from power plants. Using alkali‐based solutions for CO2 capture is thought to be an effective method to achieve this but poor CO2 sorption/desorption kinetics inhibit its development. The use of nanofluids, prepared by adding nanoparticles to an alkali‐based solution, is a promising way to improve CO2 sorption/desorption reactivity because the addition of nanoparticles not only improves the gas‐liquid mass/heat transfer but also enhances the reaction kinetics. In this paper, a nanostructured Cu/TiO(OH)2 was prepared and used to accelerate the CO2 sorption/desorption performance of a potassium‐based solution. The CO2 sorption/desorption reaction rates increased with the thermal conductivity of the nanofluid but the inclusion of more nanoparticles resulted in particle sedimentation. The potassium‐based solution containing 0.014 vol% of the nanostructured Cu/TiO(OH)2 was therefore the targeted nanofluid that gave the best CO2 sorption/desorption performance and cyclic stability. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.