Study Of The Hydration Reaction Of α-pinene

Terpineol exits in linaloe wood oil, cajeput oils, orange flower oil and plant essential oil. It is mainly used in flavor spices, medicine, pesticides, plastic and soap industry. There is small amount of natural terpineol, so it cannot fully meet the industrial demand. Therefore, it is necessary to develop good method to synthesis terpineol. There are mainly two methods to product a-terpineol, including the direct and indirect process. The mainstream of industry production method is indirect hydration in our country and abroad. The process route is:putting water and a small amount of surface active agent into a-pinene, using sulfuric acid as catalyst, taking hydration to product terpinum, then by means of dehydration to obtain crude a-terpineol, fractionating to get the perfumery grade a-terpineol at last. The indirect process has many disadvantages such as complicated operations, long production cycle, small production capacity, equipment corrosion, environment pollution and so on. In contrast, the direct process has many benefits such as high reaction rate, simple process, lower energy consumption.The effects of various parameters were investigated in detail using Lewatit2620 wet resins as catalysts and polar reagent y as solvent in a stirred tank reactor. The optimized process parameters were agitation speed of 500rpm, reaction temperature of 333.15K, catalyst loading of 0.20gcatalyst/g total soluition and m(a-pinene):m(water):m(solvents:y) of 1:0.13:2.The kinetics study is the basis of simulation, design, and amplification of industrial reactors, and is one of the main contents of chemical engineering. So the kinetics of the a-pinene hydration reaction has important significance. In this paper, a pseudo-homogeneous (PH) kinetic model was utilized to correlate the experimental data and estimated the kinetic parameters. The estimated kinetic parameters made the calculated results in excellent agreement with the experimental results, indicating that the PH model gives a good representation of the kinetic behavior for the direct hydration of turpentine. A pseudo first order model was used to explain the reaction rate equation, and reaction rate constants and reaction activation energy were determined.The reaction rate constants of each reaction obtained by the pseudo-homogeneous kinetic model are:...