Enhancement of CO2 Storage on Mesoporous Carbon in the Presence of Water

Enhancement of CO₂ Storage on Mesoporous Carbons in the Presence of Water

Jia Zhou^a, Wei Su^ab, Yan Sun^c, Xiaojing Wang^a, Shuguang Deng^d

aSchool of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China

bTianjin Key Laboratory of Membrane and Desalination Technology,Tianjin 300072,China

cDepartment of Chemistry, School of Science, Tianjin University, Tianjin 300072, China

d Department of Chemical Engineering and Materials New Mexico State University, Las Cruces, NM, 88003, USA

Carbon dioxide is a primary contributor of greenhouse gas in atmosphere. Hydrate-forming method is a promising solution to capture and store CO₂. The equilibrium isotherms of CO₂ on mesoporous carbon CMK-3 with different water contents were collected at 275K. When the water weight ratio was 0.55, a rapid increase at about 2.6MPa was observed in the isotherm, for the CO₂ hydrate was formed in the carbon pores. However, there were two sharp increases in the isotherms at the pressure of 2.1MPa and 2.6MPa respectively, as the water weight ratio was at 1.55, 1.75 and 2.35. At high water weight ratio, after the pores were fully filled with water, there still existed extra water outside the pores. As a result, CO₂ hydrate was formed in the space among carbon particles. Compared with dry CMK-3, the CO₂ adsorption capacity wet CMK-3 was improved as much as 122% at the pressure of 3.5MPa, and the highest adsorption capacity is about 41mmol/g.  

Fig 1. CO₂ isotherms of on mesoporous carbon CMK-3 with different water contents

at 275 K