Preparation method and application of biogas residue-based activated carbon with high adsorption performance

The invention discloses a preparation method of biogas residue-based activated carbon. The preparation method comprises the following steps: (1) forming biomass biogas residue through anaerobic fermentation, drying, and then pulverizing, thus obtaining biogas residue powder; (2) mixing the biogas residue powder with an activating agent under the atmosphere of inert gas, and grinding together; (3)putting the biogas residue powder obtained in step (2) in the atmosphere of the inert gas, activating under the condition that the temperature is 500 to 800 DEG C, and cooling, thus obtaining activated biogas residue; (4) rinsing the activated biogas residue to be neutral, and then drying, thus obtaining the biogas residue-based activated carbon. According to the preparation method disclosed by the invention, fermented biomass biogas residue is used as a raw material, the raw material is high in carbon content and low in cost, the raw material is microscopically expressed in a net structure formed by cellulose, hemice