Carboxymethyl chitosan thiourea resin and preparation method and application thereof

The invention relates to a carboxymethyl chitosan thiourea resin and a preparation method and an application thereof, belonging to the technical field of adsorbent resins. The preparation method comprises the following steps: using chitosan with high molecular weight to react with chloroacetic acid and synthesize carboxymethyl chitosan and then perform a series of crosslinking and chemical modification to the carboxymethyl chitosan to prepare carboxymethyl chitosan thiourea resin. The invention relates to the design, synthesis method and adsorption property of carboxymethyl chitosan thiourea resin; the prepared resin through design has good mechanical property, the introduced functional groups have good adsorption to heavy metals, and has excellent adsorption and adsorption selectivity to various heavy metals such as mercury, silver and lead, the synthesis method is simple, and the reaction conditions are relatively mild. The structural formula of the carboxymethyl chitosan chelate resin is shown below, wherein n > 1450.