Method for enriching and purifying heavy metals in seawater

The invention provides a method for enriching and purifying heavy metals in seawater, which belongs to the technical field of seawater purification, and specifically comprises the following steps: taking microcystis aeruginosa as a raw material, extracting acidic polysaccharide from the microcystis aeruginosa, performing esterification cross-linking between the acidic polysaccharide and 2-formylamino sorbitol to obtain hydrogel with a cross-linked network structure, the preparation method comprises the following steps: preparing a microcystis aeruginosa polysaccharide hydrogel, modifying the hydrogel by using sulfamonomethoxine to obtain the modified microcystis aeruginosa polysaccharide hydrogel, mixing the hydrogel with diatomite, zeolite, trigonelline and disodium epoxysuccinate to prepare the adsorbent, and putting the adsorbent into polluted seawater to adsorb heavy metal ions, the heavy metal removal effect is good, rapid removal of heavy metal ions can be achieved, secondary pollution is avoided, and t