The Preparation Of Different Acid Catalysts And Their Application In The Synthesis Of Isoamyl Isovalerate

Organic acid esters can be used industrially as raw materials and solvents for organic synthesis, synthetic perfumes. Isoamyl isovalerate is an important sort of organic acid esters, being widely used in the filed of food, pharmacy, cosmetic and so on. The isoamyl isovalerate was traditional synthesized by using sulfuric acid as catalyst and isovaleric acid and isoamyl alcohol as raw materials. However, this method for thr synthesis of isoamyl isovalerate have many disadvantages such as poor selectivity, complex manipulation, more by-product and acid waetewater. Therefore, they can be used as effective, recyclable, good thermal stability and environmental benign catalysts have great significance for the synthesis of organic acid esters.In this paper, we synthesized four different acids as catalyst in the synthesis of isoamyl isovalerate:Lewis acid-methane sulfonate, Brφnsted acid-triethylamine ionic liquids, Brφnsted-Brcpnsted acid-phosphotungstic supported on ionic liquids and Brφpnsted-Lewis acid copper tnngstophosphate. The relationship between acidity, structure and catalytic performance were studied. Besides, the amount of catalysis, the ratio of acid and alcohol, reaction time and the amount of agent which taking off water were investigated.In the chapter two, the Lewis acid-copper methanesulfonate which shows good water resistance and high catalytic acivity. Through the response surface analysis, the optimum synthetic conditions of isoamyl isovalerate:the molar ratio of alcohol and acid was1.6:1, the catalyst was5%quality of isovaleric acid, the amount of carrying water agents was9mL, response time was2.2h, under this condition, isoamyl isovalerate yield was90.1%. The reaction kinetics model was established under the optimum synthetic conditions, the activation energy Ea=48.89kJ/mol, theIn the chapter three, a series of Brφnsted ionic liquids based on triethylamine were synthesized and characterized. There catalytic activities in the synthesis of isoamyl isovalerate were investigated. Through the response surface analysis, the optimum synthetic conditions of isoamyl isovalerate were determined:the molar ratio of alcohol and acid was1.8:1, the catalyst was6%quality of isovaleric acid, the amount of carrying water agents was10mL, response time was1.5h, under this condition, isoamyl isovalerate yield was97.2%. The reaction kinetics model was established under the optimum synthetic conditions, the activation energy Ea=18.58kJ/mol, the dynamic equations was In the chapter four, in order to deal with the high costs, hard to recycling and reuse of the ionic liquids we have synthesized a series of acid-phosphotungstic supported on ionic liquids. And through the response surface analysis, were determined the optimum synthetic conditions:the molar ratio of alcohol and acid was1.2:1, the catalyst was7.2%quality of isovaleric acid, the amount of carrying water agents was8mL, response time was2.5h, under this condition, isoamyl isovalerate yield was97.5%. The reaction kinetics model was established under the optimum synthetic conditions, the activation energy Ea=32.92kJ/mol, theIn the chapter five, the inexpensive and convenient catalyst of copper tnngstophosphate were synthesized. The Cu0.5H2PW12O40which synthesized by cupric chloride and phosphotungstic acid shown the best catalytic activity. The synthetic conditions were optimized by using response surface analytical:the molar ratio of alcohol and acid was1.2:1, the catalyst was6%quality of isovaleric acid, the amount of carrying water agents was8mL, response time was2.5h, under this condition, isoamyl isovalerate yield was97.8%. The reaction kinetics model was established under the optimum synthetic conditions, the activation energy Ea=51.71kJ/mol, the dynamic equations was...