Preparation of composite biochar and method for removing thallium-containing ammonia nitrogen wastewater by using composite biochar

The invention relates to preparation of composite biochar and a method for removing thallium-containing ammonia nitrogen wastewater by using the composite biochar. The method mainly comprises the following steps: adding the composite biochar and pypocholoride into the thallium-containing ammonia nitrogen wastewater; the pomelo peel biochar prepared by taking pomelo peel as a material through a carbon thermal method being loaded with zero-valent manganese, and the loading ratio of the pomelo peel biochar to the zero-valent manganese being 1: 0.3; absorbing monovalent thallium and trivalent thallium by the composite charcoal, and oxidizing the monovalent thallium into the trivalent thallium in the adsorption process; the dosage of the hypochlorite being not more than 30mmol/L, and the synchronous removal rate of thallium and ammonia nitrogen being increased along with the increase of the dosage of the hypochlorite. The invention specifically discloses a method for removing thallium-containing ammonia nitrogen w