Method of preparing charcoal based on agricultural and forestry wastes and charcoal

The invention discloses a method of preparing charcoal based on agricultural and forestry wastes. The method comprises the following specific steps: (1), treating the agricultural and forestry wastes to obtain dry powder biomass materials; (2), placing the biomass materials into a processor which is anoxic, ventilated with a protective gas and sealed, and then carrying out two-stage heat-up treatment, wherein the heat-up treatment at the first stage is to quickly heat to 220 DEG C-260 DEG C from the normal temperature, and the heat-up treatment at the second stage is to slowly heat to 350 DEG C-750 DEG C from the final temperature of the first stage; and continuously cracking for 1 hour-3 hours without oxygen; and (3), cooling to the room temperature, and obtaining the solid charcoal by grinding and sieving the substance obtained in the step (2), activating by an activator, washing by distilled water and drying. According to the method disclosed by the invention, a preparation process is simple, material are easy to obtain and cost is low; the prepared charcoal has good adsorption characteristic on surface, is capable of adsorbing and removing various pollutants in an environment medium, and has a wide application prospect in the fields of agriculture and environment.