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Propylene oxide is an important organic intermediates addition to the polypropylene and acrylonitrile third propylene derivatives. Currently, the global propylene oxide is a 5% average annual market demand is growing, and has broad market prospects. Methods of industrial production of propylene oxide are mainly two kinds of the epichlorohydrin law and co-oxidation. Epichlorohydrin production process wastewater generated a large amount of corrosion of the equipment, environmentally unfriendly exists; co-oxidation process is long, complicated process, production equipment and raw materials more stringent requirements, higher investment costs and other shortcomings, However, due to its high product yield, subsequent processing easier, less pollution, co-product revenue and high economic benefit. The Arco process as the representative of the total oxygen technology patents belonging to foreign countries, the majority of domestic enterprises faced technical barriers and safety and other issues still use traditional chlorohydrin process. Therefore, the development of environmentally friendly propylene oxygen preparation of propylene oxide process, has important application value. In this paper, tert-butyl hydrogen peroxide as the oxygen source, molybdenum hexacarbonyl as catalyst propylene epoxidation synthesis of propylene oxide, molybdenum hexacarbonyl catalyst is first prepared, and FT-IR, ICP-AES and other means were characterized, hexacarbonyl molybdenum and molybdenum-based homogeneous catalyst were evaluated, the results showed that the catalytic reaction effects of of hexacarbonyl molybdenum in the system best. The product tert-butyl hydrogen peroxide content using High Performance Liquid Chromatography under optimized chromatographic conditions, the components of the propylene epoxidation system can be completely within 4min peaks, and to obtain a good separation. The results showed that the tert-butyl hydrogen peroxide has a good linear relationship, the correlation coefficient of 0.9998, the recovery rate was 99.42% ~ 101.17%, reproducibility relative standard deviation of 0.36% to 0.52%, reproducibility relative standard deviation of 0.79 % by pH. The higher the precision and accuracy of the method, and the analysis of fast, simple, economic, and is an ideal detection analysis method. Select molybdenum hexacarbonyl as a catalyst, using single factor experiment investigated the catalyst concentration, reaction temperature, the molar ratio of propylene with t-butyl hydroperoxide (alkylene ratio), reaction time and other factors of the oxidation reaction of the epoxidation reaction. examine the impact of a cobalt salt additives on the reaction the dehydration process optimization. The results showed that, after the dehydration of the raw material is dried over anhydrous magnesium sulfate, molybdenum mass fraction for the 1.7 x 10-4, a reaction temperature of 120 ° C, alkylene than 6.5:1, the reaction time of 1h, the reaction to obtain a good effect, TBHP The conversion was 82.82%, propylene oxide selectivity of 91.87% (with respect to the TBHP). To investigate the catalytic mechanism of the co-oxidation reaction, using gas chromatography - mass spectrometry analysis of the reaction product, and infer the reaction pathway. The results show that in the epoxidation of propylene system, and byproducts, including propylene glycol isopropyl ether and t-butyl. The former is generated by the hydrolysis reaction product of ethylene oxide with the system water; while the latter reaction at high temperatures generated by the primary product of propylene oxide and co-product tert-butoxide.
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