Exploring the performance in co2 uptake of low cost carbon-based materials

Post-combustion CO2 capture strategy is one of the most advantageous approach for Carbon Capture and Storage (CCS) since it can be applied without radical changes on the plants architecture [1]. CO2 adsorption with solid sorbents is one of the most promising options for post-combustion CO2 capture. A variety of promising materials acting as CO2 physisorbent and/or chemisorbent have been reviewed [2] including activated carbons, microporous/mesoporous silica or zeolites, carbonates, polymeric resins nitrogen-functionalized, metal-organic frameworks, metal oxide, ionic liquids. Sorbent selection is a key point because the materials should be both convenient from the economic point of view and versatile over a wide range of temperature and pressures. Moreover the possibility to tolerate repeated cycles of CO2 absorption and desorption is also desirable. This work investigates the absorption behavior of CO2 of materials prepared starting from a low-cost commercial carbon black. Carbon black offers a surface prone to be modified in quite mild condition allowing both chemical functionalization and physisorption with a large array of molecules. Aim of this study is to explore the role of the surface features of the substrate in the designing competitive sorbents for CCS strategies. Three CB surface modifications were proposed, namely oxidation and functionalization with ammino-groups, coating with magnetic iron oxides (magnetite Fe3O4) and impregnation with ionic liquid (IL). A careful characterization of chemical-physical properties, including textural and morphological features of the CB-based sorbents, was performed. The ability to act as CO2 sorbents was evaluated on the basis of the breakthrough times measured in a lab-scale fixed bed set-up.