| 摘要 |
FIELD: chemical industry. SUBSTANCE: method involves charging into reactor with mixer 2-28% solution of sulfuric anhydride in sulfuric acid, dosing 30-34% solution of H2O2 and powder crystalline graphite is added in batches. Mass ratio graphite : sulfuric anhydride solution in sulfuric acid : hydrogen peroxide = 1 : (5-6) : (0.15-0.2), respectively. Mixture is stirred for 30 min at (40 ± 10) C, cooled and squeezed out. The sulfuric anhydride spent solution can be feed to the repeated using. Oxidized graphite is washed out with water, squeezed out and placed to ammonia aqueous solution at stirring for 30 min at temperature no exceeding 40 C followed by squeezing out, washing out with water and drying. Acid washing waters are neutralized with spent ammonia and ammonia washing waters and formed ammonium sulfate aqueous solution is used as mineral fertilizer. After thermal treatment at 900 C the value of graphite bulk density is less 6 kg/m3. The process is explosion-proof, amount of washing out waters is diminished. Invention can be used in preparing heat-insulating filling agent of fireproofing compositions, structural materials, catalysts and sorbents. EFFECT: improved preparing method. 1 tbl, 11 ex
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