Studies Of Orderly Mesoporous Materials For Adsorption Application

A big problem facing human being is to find out an appropriate alternative fuel to release the pressure on petroleum demand. Natural gas, such a clean, renewable energy sources, will take up the greater ratio in the framework of China energy. NGH (natural gas hydrate) to 10 MPa may achieve a theoretical volume reduction factor of 164 or even higher, and the storage cost is 26% lower than CNG. A test on charging/discharging process proved that pore space catalyzes the formation of hydrate and 63% more methane was stored per unit mass of activated carbon, if water is pre-adsorbed in carbon. The mesoporous sieves have high specific surface area , adjustable pore size and large pore volume and maybe have high methane Storage. Therefore, we synthesized mesoporous materials (MCM-41,SBA-15,CMK-3), and methane storage capacity in different materials are researched by pre-adsorbed water. The highest sorption amount of 41.22 wt% in CMK-3-1.25 was recorded at 275 K and 6.72 MPa, which is 31% higher than the largest sorption capacity observed on wet activated carbon. The enhancement mechanism of water pre-adsorption is attributed to the formation of methane hydrate. The enthalpy change determined from the inflexion pressure is in agreement with the enthalpy change of the methane hydrate formation reported in literature.The effect of greenhouse gases is considered responsible for the severe change of the weather. Emission of CO₂ and CH₄ has received the world's concern since more and more weather disasters happen recently. Therefore, capture of green house gases is very important from the point of view of environment protection. Therefore, SBA-15 and CMK-3 of different pore sizes and specific surface areas are studied the separation possibility for the mixture of CH₄, N₂ and CO₂ based on the differences in the equilibrium adsorption。TEA (Triethanolamine) is used to modify the orderly mesoporous silica, SBA-15, and efficient separation between CO₂ and CH₄ is observed in the present study. This sorbent is advantageous over the others in that it is a selective sorbent of CO₂ and can be regenerated easily at the ambient temperature. therefore, TEA-modified SBA-15 sorbent can be applied in the pressure swing operation, which will provide an efficient and cheap method for the capture of carbon dioxide and methane.