Research On Catalysis Process Of Gas Phase Ammoximation Of Cyclohexanone And Gas Phase Ammoniation Of Cyclohexene

Caprolactam is often used in textile,packaging and many other industrial areas,but the traditional production of caprolactam process mainly by "cyclohexanone-hydroxylamine" routes.there are plenty of environmental pollution and production economic problems.Aiming to solve the problems of the liquid cyclohexanone ammoxidation reaction,we use the ammonia,molecular oxygen and cyclohexanone as ingredient,using self-designed fixed bed reactor under the condition of the gas phase of cyclohexanone ammoxidation reaction.Using cyclohexene as raw material,bypassing the cyclohexanone preparation process for the synthesis of caprolactam process has a profound impact.So in this paper,the direct reaction of cyclohexene as raw material and ammonia gas ammoniation take some exploratory research.The work summary of this paper:We prepared series mesoporous molecular sieve by the method of hydrothermal synthesis,included HMS,MCM-41 and SBA-15,taking these composed of pure SiO2 molecular sieve as catalyst,used in catalytic cyclohexanone ammoxidation in the gas phase reaction.Compare with other catalysts,SBA-15 showed more superior catalytic performance,but the overall catalytic performance is not very meliority.Take SBA-15 as the catalyst carrier,loading Al,W and Ti to examine the different metals catalytic performance,optimizing the conditions and when Ti load of 0.5%of TiO2/SBA-15 catalyst is most appropriate,through the single factor investigate experiment,the optimal experimental conditions:1.2 g catalyst,180?,ammonia oxygen ratio is 3:1,traffic for 60 mL/min,cyclohexanone conversion rate can reach 25%,the selectivity of cyclohexanone oxime is 80%,catalyst running first fall after rise trend,run ten hours of cyclohexanone selectivity can still remain at around 60%.The main purpose of this paper is to reduce the reaction conditions of the experiment,expect to the catalytic reaction under atmospheric pressure.Discusses the experimental conditions effect of the different carrier,active component in the existing through the single factor investigation.To optimize the conditions for:catalyst:H2SO4/SiO2 10 g,charge capacity:6 mmol/g,ammonia flow:30 mL/min,cyclohexene feed rate:0.02 mL/min,the reaction temperature is 280?,the cyclohexene ammoniation results is the best,cyclohexene conversion rate above 1%,selectivity of cyclohexylamine can also remain above 80%.At the same time,we found that the cyclohexene ammoniation selectivity under the condition of normal pressure is very high,by-product is given priority to with the cyclohexanol and trace of cyclohexene polymers,the generation of cyclohexanol mainly because of the catalyst and raw material contains a small amount of water.