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Cyclohexanone synthesis of caprolactam , adipic acid and caprolactone important intermediates , paint , ink solvent , the domestic production capacity of 60 million tons / year , more than 90% of cyclohexane catalyzed air oxidation , but the technology exists high energy consumption , waste liquid alkali emissions from large drawback . Using cyclohexane as the raw material and air as the oxygen source in a 1L autoclave , examine the protective effects of glycol on the carbonyl group of cyclohexanone , sodium carbonate hydrogen peroxide stabilizing effect of cyclohexyl , and phosphomolybdate pair of catalysis . Experimental results show that : Na2CO3 glycol though in cyclohexane under oxidizing conditions can be generated with cyclohexanone glycol cyclohexanone ketal , but produces a slow , little effect on the protection of the carbonyl group of cyclohexanone ; cyclohexyl hydrogen peroxide have a good stabilizing effect , improve the selectivity of the oxidation reaction , the optimum reaction temperature of 160 ℃, the optimum amount of addition of sodium carbonate to 0.2 g/600ml cyclohexane conversion rate of the oxidation reaction 4 % , the selectivity of more than 92% , but also inhibit the oxidation reaction rate ; heteropolyacids phosphomolybdate good catalysis of the oxidation of cyclohexane , can accelerate the oxidation reaction at the same time the speed and the choice of the reaction , the optimum reaction temperature of 158 ℃, the phosphomolybdate optimum amount for 0.0122g/600ml cyclohexane , 4.15% conversion rate of the oxidation reaction , the selectivity is 92.5% or more , and the oxidation product cyclohexyl peroxide the hydrogen content of more than 60% lower than the non-catalyzed oxidation , which reduces the consumption of sodium hydroxide in exploded cyclohexyl hydrogen peroxide is correspondingly thus reducing the emissions of waste alkali . The phosphomolybdate catalytic air oxidation of cyclohexane technology three oxidation technology in the most economic technology with high reaction selectivity , the waste liquid alkali emissions and environmentally friendly characteristics , with good prospects for industrial applications .
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