Fundamental Researches About The Esterification Of Camphene

Turpentine can be transformed into a variety of valuable product such as camphor, camphene, isobornyl acetate by different chemical reactions and processes. Isomerization of a-pinene to camphene and acetoxylation of camphene to isobornyl acetate are the key steps of synthesizing camphor using α-pinene as starting material.The optimal condition of the acetoxylation of camphene in a batch reactor was obtained in our team. But the study of the effects of water content on the acetoxylation of camphene is indispensable. The esterification process in a fixed bed reactor has a few disadvantages, such as side reaction and uneven distribution of temperature. The separation and purification steps should be included in the whole production process, and the saturated vapor pressure and the molar enthalpy of vaporization were very important. The thermodynamic parameters and can be used in the design and operation of multicomponent system.The thesis contained the following chapters:(1) To establish to what extent additional water affects the rate of the conversion of camphene and acetic acid into isobornyl acetate, a reaction was performed in which extra water was added and the optimal conditions in a batch reactor were temperature 40℃, agitation speed 400 rpm, catalyst mass fraction 10% and molar ratio of acetic acid to camphene 1.1:1. The increase in the rate of the reaction by addition of water (less 101800ppm) is attributed to an enhanced rate of proton transfer and conversion of camphene, in contrast, the decrease in the rate of the reaction and conversion of camphene by addition of water (exceed 101800ppm) to an reduced rate of proton transfer. The data were correlated by a pseudo-homogenous model and the result was very well. The experimance data and calculate data were verified by statistical tests.(2) Experiments of continuous synthesis of isobornyl acetate was studied in a inpseudofluid suspended bed reactor with camphene and acetic acid as raw materials and cation exchange resin CT800 as catalyst. The experiments were carried out in a stainless steel column with 0.32m inner diameter. The effects of various parameters, e.g. catalyst mass fraction, mole rate of acetic acid to camphene and feed space velocity were studied. The optimal conditions in inpseudofluid suspended bed reactor were catalyst mass fraction 66%, the reaction space velocity 0.09 h-1, and molar ratio of acetic acid to camphene 1.1:1.(3) The vapor pressures of camphene, acetic acid and isobornyl acetate were determined in the range of 309K to 473K by boiling point method. The vapor pressure data were fitted by the Antoine equation and the parameters A, B and C were obtained by using a regression method of Hooke-Jeeves pattern search with Matlab softwar. The molar enthalpies of vaporization for each compound were calculated. The function of ΔvapHm and temperature was obtained by Clausius-Clapeyron equation and the ΔvapHm value was estimated for camphene, acetic acid and isobornyl acetate.