▎ 摘　　要

NOVELTY - The preparation method of biomass-based hydrogel involves adding sodium lignosulfonate and lignosulfonate to an aqueous solution of graphene oxide and then uniformly mixing, stirring the mixture at high-speed, adding acrylamide, N-hydroxymethylacrylamide, hydrogen peroxide and calcium chloride to the mixture and then stirring at high-speed to obtain a homogeneous mixed solution, transferring the homogeneous mixed solution to a reaction container, introducing inert gas into the reaction container at room temperature, and reacting. USE - The method is useful for preparation of biomass-based hydrogel, which is useful as organic dyes and heavy metal ion adsorption material (claimed). ADVANTAGE - The method enables simple and economical preparation of biomass-based hydrogel with high purity and absorption capacity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) biomass-based hydrogel prepared by the method; and (2) use of biomass-based hydrogel as organic dyes and heavy metal ion adsorption material.