Adsorbent and preparation method and application thereof

The invention belongs to the technical field of wastewater treatment, and discloses an adsorbent as well as a preparation method and application thereof. The adsorbent comprises titanium hexametaphosphate, the titanium hexametaphosphate is mainly prepared from hexametaphosphate and titanium salt. The adsorbent is an aggregate of micron-sized or nano-sized particles, has a large surface area and good adsorption performance, and can be used as a sewage treatment agent to effectively remove thallium pollutants in various water bodies such as underground water, surface water, chemical wastewater,mine wastewater and the like, and the removal rate reaches 99.8%; and the adsorbent also has a good capability of removing heavy metals such as cadmium, lead, copper, antimony, cesium, uranium and thelike in water. The adsorbent is wide in applicable pH value range, and particularly has good adsorption capacity, stability and heat resistance under acidic conditions. The preparation method is simple to operate, low in reac