Use of nanoparticles Cu/TiO(OH) 2 for CO 2 removal with K 2 CO 3 /KHCO 3 based solution: enhanced thermal conductivity and reaction kinetics enhancing the CO 2 sorption/desorption performance of K 2 CO 3 /KHCO 3

Global climate change resulting from substantial CO 2 emissions is increasingly attracting attention, and coal‐fired power plants are a major source of CO 2 emission, so it is necessary to control and reduce CO 2 emissions from power plants. Using alkali‐based solutions for CO 2 capture is thought to be an effective method to achieve this but poor CO 2 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 CO 2 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 CO 2 sorption/desorption performance of a potassium‐based solution. The CO 2 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 CO 2 sorption/desorption performance and cyclic stability. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.