| 摘要 |
FIELD: industrial organic synthesis. SUBSTANCE: invention provides non-emulsion two-stage process for air oxidation of cumene in absence of initiators, catalysts, additives, and alkali agents in at least two reactor system. In the first one, cumene conversion at temperature up to 111-95 C is maintained at the level at least 16%. Process is carried out in countercurrent reactor using pure, alkali agent-free cumene. First-stage oxidation products are treated with ammonium hydroxide solution until pH at least 8 is reached. When two or more second-stage reactors are available, oxidation products are treated in each subsequent rector of the system. Conversion of cumene in the second oxidation stage is maintained at up to 25 wt % at temperature at least 100-85 C, oxidation charge and oxidizing agent being supplied concurrently. In all first- and second-stage reactors, pressure is maintained at least 4 atm and molar ratio of supplied oxygen to maximally consumed oxygen is maintained within a range of 1.12-1.30. Oxidation products from the last second-stage oxidation reactor are distilled to give industrial-grade (63-93%) cumene hydroperoxide. Excessive cumene is returned into process to be treated with aqueous ammonium solution to pH 9-10. Recycle cumene from hydrogenation stage and fresh cumene are treated with mixture of 5-10% aqueous NaOH solution and 5-10-% aqueous sodium carbonate solution. Combined streams of the above-mentioned cumenes are washed with water at cumene-to-water ratio 1: (0.15-0.20). Concentration of cumene hydroperoxide in product rises with rate 2.5 to 4.5% per hour, while selectivity is not below 94 mol % and cumene conversion 21-22 mol %. EFFECT: increased productivity. 2 cl, 1 dwg, 2 tbl, 5 ex |
