METHOD OF DEMINERALIZATION OF THE CARBON RESIDUE OF THE PYROLYSIS OF USED TIRES Russian patent published in 2023 - IPC C08J11/00 B29B17/00 

FIELD: tire recycling.

SUBSTANCE: invention relates to a method for demineralization of high-ash carbon residue from the pyrolysis of used tires. To implement the method, the first step is to carry out magnetic demineralization of the carbon residue of the pyrolysis of waste tires using cylindrical magnets on an inclined surface with a slope of 12°. At the second stage of exposure, the high-ash carbon residue is moistened in a 10% water-alcohol solution at the rate of 1 litre of solution per 1 kg of carbon residue from waste tire pyrolysis. The residue is treated with a 35% hydrochloric acid solution at the rate of 1 litre per 1 kg of carbon residue from the pyrolysis of waste tires and stirred for 10 hours under thermostatic conditions at a temperature of 85°C. After that, the residue is washed until a neutral reaction of the wash water is reached. The third stage of exposure is the treatment of the carbon residue of the pyrolysis of used tires with a 10% aqueous solution of sodium hydroxide at the rate of 1 litre per 1 kg of carbon residue and stirring for 10 hours at a temperature of 85° C. The carbon residue is then washed until the wash waters are neutral. The last stage of exposure is the treatment of the carbon residue of the pyrolysis of used tires with a 40% aqueous solution of hydrofluoric acid at the rate of 1 litre per 1 kg of carbon residue and stirring for 10 hours at a temperature of 85°C. After that, the treated carbon residue of pyrolysis is separated by filtration, washed until a neutral reaction of washing water is reached, and dried at a temperature of 105°C until constant mass is reached.

EFFECT: removal of metals from the high-ash carbon residue of waste tire pyrolysis, reducing the ash content in the carbon residue of waste tire pyrolysis to less than 1 wt.% without exposure to high temperatures and pressures.

1 cl, 2 tbl, 1 ex