The existing manufacturing process path of cyclohexanol as well as cyclohexanone is to initially oxidize cyclohexane with molecular oxygen without catalysis to generate an oxidation mixture consisting of cyclohexyl hydroperoxide as the primary item; and afterwards break down cyclohexyl hydroperoxide., to generate cyclohexanol as well as cyclohexanone; and afterwards acquire cyclohexanol and also cyclohexanone items through distillation. In the catalytic decomposition procedure of cyclohexyl hydroperoxide, 2 different catalytic decomposition processes are presently utilized on the planet: one is the uniform catalytic disintegration procedure of tert-butyl chromate designed by the French company Rhodia, and also the various other is invented by DSM of the Netherlands. Heterogeneous catalytic disintegration process of cobalt acetate under alkaline aqueous salt hydroxide remedy. Both procedures are low-temperature decomposition processes improved the basis of the conventional uniform catalytic oxidation and also NaOH aqueous solution saponification decomposition procedures from the 1950s to the 1970s.
Although the molar yield of the homogeneous catalytic decay procedure of tert-butyl cyclohexyl hydroperoxide hydrochromate in the decay process is as high as 94%, there are two vital imperfections in the uniform catalytic disintegration procedure of tert-butyl cyclohexyl hydroperoxide hydrochromate: First One negative aspect is that during the disintegration procedure ranges, generally composed of chromium adipate, are created, which clog equipment and pipelines. Currently, Rhodia makes use of octyl phosphate as a range inhibitor, but the scaling issue has actually not been entirely fixed. The constant manufacturing cycle is only four months, and it needs to be closed down for cleansing as well as descaling 3 times a year. An additional problem is that the decomposition conversion rate is low, the molar conversion rate is only about 92%, as well as the broken down material still has around 0.5% cyclohexyl hydroperoxide. This part of cyclohexyl hydroperoxide decomposes under high-concentration alcohols and also ketones, high level of acidity and also heat problems in the alkane healing tower and also alcohol-ketone product tower, as well as mostly creates acidic and also caprolactone-based ester compounds such as adipic acid, and also It quickens the totally free radical condensation reaction of alcohols as well as ketones as well as the esterification response of alcohol, creates a large amount of high boiling issue, and also decreases the overall yield of the gadget. Currently, the total molar return of domestic and foreign commercial tools utilizing this process has to do with 80%.
The existing heterogeneous catalytic disintegration procedure of cobalt acetate utilizing salt hydroxide alkaline aqueous service for cyclohexyl hydroperoxide has three major flaws: first, decay side reactions are big, and also the molar yield of decomposition is low, only 84%; 2nd,, the cyclohexane oil stage having cyclohexanol as well as cyclohexanone is tough to completely divide from the alkali aqueous phase including waste alkali. A specific amount of waste antacids liquid phase is always entrained in the oil stage, so that it will not be utilized in the succeeding purification. Waste alkali scaling happens in the tower, obstructing the distillation tower and also its reboiler, so that the constant manufacturing cycle is often only half a year; 3rd, the alkali usage is high, the waste antacid discharge is big, as well as the 0! Γ ion concentration in the waste antacid remedy is It must be controlled at about 1 mol/L. When it is greater than 1 mol/L, the incineration treatment of waste antacids becomes more difficult. When it is less than 1 mol/L, the decay conversion rate is reduced. Part of the cyclohexyl hydroperoxide will be made use of in the alkane recovery tower and also alcohol in the succeeding processes. The ketone item tower remains to disintegrate, mostly creating caprolactone as well as organic acids, which reduces the general return of the device and influences the quality of the cyclohexanone item. Presently, the total molar return of domestic as well as international industrial devices utilizing this process is just around 80%.
At present, the cyclohexyl hydroperoxide decomposition procedures of significant domestic and foreign business use one of these 2 processes to finish the one-step decomposition process. The developer has actually divulged a two-step decomposition procedure in Chinese licenses ZL94110939.9 and also ZL98112730.4 specifically. In the very first step, the alkalinity is minimized and the blood circulation volume of the alkali aqueous stage is increased, and a static mixer is used. Industrial implementation results prove that the total molar yield is indeed boosted, yet the separation of the cyclohexane oil stage and the spent alkali liquid stage comes to be more difficult. Presently, the overall molar return of domestic commercial production gadgets making use of the innovator’s complete collection of process modern technology is only around 82%.
