Studies On Preparation Of Mesoporous Active Carbon From Corncobs And Its Applications

Activated carbons (ACs) with developed porosity are extensively used in many fields of people life. The adsorptive capabilities of ACs are associated with their internal developed porosity and high specific surface area.Microporous activated carbon with large specific surface area(2000-3000m2g-1) are often used for gas sorption. Due to the large pore size and volume and the relatively high specific surface area, mesoporous activated carbons find many applications for loading catalysts or other chemicals in material engineering and chemical engineering. Presently, manufacture of mesoporous carbon materials have been received an increasing research interest.A big problem facing human being is to find out an appropriate alternative fuel to release the pressure on petroleum demand. Natural gas is a clean fuel with relatively abundant resources. It was reported that much more methane would be stored in carbon in the presence of water. In this study, ACs with high surface area and high mesopore portion were prepared from cobcorns by H3PO4 activation. We study the effects of chemical ratio ,soating temperature,soating time,concentration of H3PO4, activation time and activation temperature.By the orthogonal tests , we find the optimum method to prepare mesoporous ACs named PMC-1.The pore volume of PMC-1 is 1.72cm3,the specific surface area of it is 1610m2g-1, the mesoporous porosity ratio of PMC-1 is 66%.We study the capability of sorption of N2, CH4, CO2, H2 on microporous and mesoporous Acs.We find the amount of sorption on micropourous ACs is larger than that on mesoporous ACs at the same conditions.Methane sorption in the ACs showed that the sorption amount in wet ACs is much higher than that on the dry one. The amount of CH4 sorption on PMC-1(Rw=1.95) is 17% at 277.15K under pressure of 7.5MPa.The enhancement mechanism was attributed to the formation of methane hydrate.We also have studied the effects of water raito, temperature, the pore size and surface character.We find the amount of sorption of CH4 on BY-2-6(Rw=1.03) is 28% at 277.15K under pressure of 9MPa,since it's focused pore size(2-3nm) and large volume of mesoporosity.