Method for preparing high-proportion microporous activated carbon based on hemicellulose pre-extraction, high-proportion microporous activated carbon and application of high-proportion microporous activated carbon

The invention discloses a method for preparing high-proportion microporous activated carbon based on hemicellulose pre-extraction, the high-proportion microporous activated carbon and application of the high-proportion microporous activated carbon. The method comprises the following steps: carrying out alkali extraction on a fiber raw material, carrying out solid-liquid separation, precipitating filtrate by ethanol to obtain hemicellulose, washing and drying solid residues to obtain a pre-extracted raw material, carbonizing the pre-extracted raw material in inert gas to obtain a carbonized solid, mixing the carbonized solid and an activating agent into water, drying, activating in inert gas, pickling, and drying to obtain the high-proportion microporous activated carbon. According to the method, high conversion and utilization of hemicellulose in biomass are achieved, meanwhile, the carbon yield is maintained, the micropore specific surface area and the pore volume of the prepared activated carbon are remarka