FIELD: invention relates to sulfuric acid-mediated processing of titanium containing materials to produce pigment or metallurgical titanium dioxide, and so method can be used in metallurgy, chemical, and varnish and dye industries. SUBSTANCE: method includes decomposition of titanium- and silicon- containing stock with 70% sulfuric acid at heating, dissolution of sulfatization product in aqueous medium resulting in formation of titanium-containing solution, filtration, and isolation of desired product with known procedures. Proposed method is distinguished with that initial stock is a heterogeneous mixture of titanium carbonitride and silicon carbide and decomposition is carried out at sulfuric acid to titanium dioxide weight ratio (1.35-1.55): 1 with 3.16-3.2 t of nitric acid added per 1 t of titanium dioxide. EFFECT: essentially reduced loss of titanium dioxide and one more useful product - silicon carbide produced.
