Carbon-Template-Solvothermal Reactions

Takumi Watanabe, Md Khan, Hirofumi Kanoh, Tomonori Ohba
2017 Phys Chem Ind J   unpublished
Introduction The effects of global warming and climate change are receiving increasing attention [1, 2] . In particular, emphasis has been placed on the control of CO 2 emissions, the main source of which is generally fossil fuel combustion [3, 4] . The selection of an appropriate technology for CO 2 capture depends on many factors such as the partial pressure of CO 2 in the gas stream, recyclability, sensitivity to impurities, capital and operating costs, and environmental impact [2] . Based
more » ... mpact [2] . Based on the methods used for the separation of the components of a gas stream, absorption, adsorption, cryogenic distillation, or membrane purification can be applied for CO 2 capture [5] . Liquid absorbents need to be changed and may be corrosive and toxic, cryogenic distillation is a costly process, and membranes are efficient for the separation of relatively high concentrations of adsorbate. Therefore, of these four technologies, we focused on adsorption, which is desirable because of the easy recovery of the adsorbent using temperature or pressure fluctuations, thereby reducing the cost and energy consumption [5] [6] [7] [8] . Suitable ©Abstract Separation of CO 2 using adsorption and membrane separations can be performed under moderate conditions for carbon capture and release processes. Although porous media work well for this purpose, these novel materials must be fabricated with high CO 2 separation ability. We propose the use of nanoscale BaTiO 3 crystals as separators for CO 2 adsorption. Although BaTiO 3 is a conventional ceramic, it exhibits high dielectric properties and shows potential for a strong interaction with the quadrupole moment of CO 2 . However, this high adsorption potential is reduced by the extremely small surface area of BaTiO 3 . Here, we fabricated nanoscale BaTiO 3 crystals with high surface area and nanopores, and demonstrated their excellent CO 2 adsorption performance with large adsorption hysteresis. The CO 2 adsorbed in the nanoscale BaTiO 3 crystals could be perfectly released under vacuum conditions. The structure of adsorbed CO 2 was similar to CO 2 solid at 1 GPa. The unique adsorption properties of CO 2 in these nanoscale BaTiO 3 crystals are of interest for the development of materials with high CO 2 adsorption ability.