Adsorbent as well as preparation method and application thereof

The invention relates to an adsorbent and a preparation method and application thereof, and belongs to the technical field of environmental protection. The method comprises the following steps: obtaining calcium oxide component-containing particles and kaolin particles; mixing the particles containing the calcium oxide component, the kaolin particles and the substance containing the hydroxyl ion component, and then carrying out hydrothermal reaction to obtain an intermediate product; and cooling the intermediate product, and sintering to obtain the adsorbent, the high-efficiency adsorbent with a large specific surface area is synthesized in situ by using cheap raw materials with high calcium carbonate content in nature or sodium-silicon slag, calcium-silicon slag and kaolin capable of providing calcium oxide as raw materials, and compared with a mesoporous alumina adsorbent, the adsorbent has the advantages that the addition of an organic solvent can be avoided; therefore, corrosion of the organic solvent par