Plasma-catalysis coupling for CH4 and CO2 conversion over mesoporous macroporous Al2O3: Influence of the physico-chemical properties

Macro-mesoporous alumina, calcined at different temperatures (from 400 to 800 degrees C), were tested in dry reforming of methane reaction under plasma discharge at a fixed deposited power (P = 8 W) with a ratio CO2/CH4 = 2. Besides alumina materials, the one possessing the lowest surface area (72 m(2) g(-1)) exhibited the highest activity: Methane conversion reaches 31.3 % against 23.4, 22.6 and 26.8 % for alumina calcined at 400, 600 and 800 degrees C, respectively, suggesting that the active sites generated into the mesoporosity of alumina (Al2O3 400) are not accessible to reactants under the plasma discharge. Reactant transformation is promoted with the alumina possessing the highest number of acid and basic sites and a correlation is proposed. It is believed that CH4 and CO2 adsorption are improved over acid and basic sites at the surface of alumina, favoring the production of syngas.