Recovering carbon black from scrap tyres - by pyrolysing the tyres, recovering the solid residue and treating with an aq. acid soln.

摘要

Method comprises (1) subjecting the tyres to pyrolytic degradation at >=450 degrees C, esp. >500 degrees C for >=2 hours, (2) separating the solid fraction from the gaseous and liq. fractions (3) separating metallic particles from the solid residue, e.g. by magnetic means and (4) treating the solid fraction with an aq. acid soln. such as HCl, H2SO4, H3PO4 or methanesulphonic acid at 50-200 degrees C for >=1 1/2 hrs. Process allows economical recovery of carbon black from scrap tyres and represents an important means for recycling raw materials and saving energy. The carbon black produced is of high quality and meets the requirements for toluene extraction, ash content, sulphur content and volatiles for use in tyres.