Capture of CO2 on γ-Al2O3 materials prepared by solution-combustion and ball-milling processes

A series of porous gamma-Al2O3 materials was prepared by solution-combustion and ball-milling processes. The as-prepared powders were physicochemically characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and N-2 physisorption measurements and their performances in CO2 adsorption at different pressures (0.5 to 1.5 MPa) and temperatures (40 to 60 degrees C) were investigated. It was found that gamma-Al2O3 synthesized by the solution-combustion process and ball milled at 10 hr exhibited the best CO2 adsorption performance at 60 degrees C and 1.5 MPa, achieving a maximum of 1.94 mmol/g compared to the four studied materials, as a result of their interesting microstructure and surface properties (i.e., nanocrystallinity, specific surface area, narrow pore size distribution, and large total pore volume). Our study shows that the gamma-Al2O3 prepared by solution combustion followed by ball milling presents a fairly good potential adsorbent for efficient CO2 capture. Implications: In this work, gamma-Al2O3 materials were successfully obtained by solution combustion and modified via ball milling. These improved materials were systematically investigated as solid adsorbents of accessible surface areas, large pore volumes, and narrow pore size distribution for the CO2 capture. These studied solid adsorbents can provide an additional contribution and effort to develop an efficient CO2 capture method as means of alleviating the serious global warning problem.