NMMO Solubilization Characteristic To Plant Base Lignocellulose And The Preparation And Characterization Of Lignocellulose Activated Carbon

Hemp stem powder was used as the raw material and its solubilization characteristic research in NMMO·H2O/DMSO was conducted. The surface functional groups and crystallization of the celuloses were investigated by FT-IR, XRD and NMR. Comparision had been made to the cellulose gained by traditional method. The results showed that the dissolution property of NMMO increased along with the decrease of the particle size of hemp stem powder. With further decrease of the particle size to>240 meshes, the hemp stem powder disolved in NMMO·H20/DMSO solution totally. Along with the decrease of the particle size of hemp stem powder, the yield of NMMO cellulose increased and the purity of lignin rich fractions increased. Traditional cellulose is celluloseⅠ, and cellulose abtained by NMMO/DMSO method is celluloseⅡwhich possess the similar functional groups as triditional cellulose. The FT-IR characteristic peak also showed that the celluloses abtained by these two methods were free of lignin, and comparing with Klason lignin, NMMO lignin contained a certain amount of hemicellulose and lignin, however, the structure of lignin hardly changed during the seperation process, which indicated that NMMO method can isolated relatively pure cellulose from lignocelullose based plants.Carbonization and activation research of hemp stem powder that without hemicellulose and cellulose have also been carried out. Based on the study of contributions of hemicellulose and cellulose to the specific surface area and surface texture of activated carbon during the carbonization and activation process, nitrogen adsorption, SEM, FTIR, as plot and DFT methods were introduced. The results revealed that, during the carbonization and activation process of hemp stem powder, cellulose provided a much more important contribution than hemicellulose to the specific surface area and surface texture of activated carbon. The hemicellulose had a certain contribution to the mesopore and the surface area increases with the dicrease of hemicellulose content in hemp stem powder. Activated carbon prepared by hemp stem powder that without cellulose had a lower specific surface area. The total pore volume and micropore volume were decreased and the mesopore disappeared, which indicated that cellulose mainly form the mesopore and micropore during carbonization and activation process.