Study On The Reaction And Mass Transfer Of Ozone With Olefine

This dissertation has been studied the reaction and mass transfer of gas? liquid phase ozone reaction with olefine for the demand of the deep process of cinnamaldehyde, styrene, anethole with ozone. At first, the reactivity and substituent抯 effect of quite a few olefins were analysized, and a Hammett equation fitted for the simple define ozonization was obtained according to the linear free energy relationship of organic reactions. The Hammett equation was more accurate than the methods of Atkinson on estimating the olefine ozonization rate constant. The second, the reactions of ozone with annimadehyde tyrene system and styrenenethole system were studied with the relative rate constant technique. The relative rate constant ratio expression was deduced and the rate constants of cinnamadehyde and anethole obtained relative to k2(03+styrene)=1 .3e+4lmor?were: cinnamaldehyde,720 lmor?s~ ;anethole, 3.33e+5 lmoF?s?So the reactivity sequence of the three phenyl alkene was anethole>styrene>annimadehyde. It was a good agreement with the result of the competitive ozone reaction with anethole styrene ?annimaldehyde system. The third, based on the film theory, the ozone reaction dynamic regions of three phenyl alkenes have been investigated. The result showed that the reaction of ozone with annimaldehy belonged to pseudo-first-order fast reaction dynamic region, and the ozone absorption process was controlled by the ozone reaction and the ozone mass transfer in gas phase. As for anethole, the ozone reation belonged to instantaneous interface reaction dynamic region, and the ozone absorption process was only controlled by the ozone mass transfer in gas phase. The forth, the reaction of ozone with annimaldehyde or styrene was carried out in difference bubble columns, the experiments showed that, if the ratio of column height/diameter was no more than 10:1, neither column height nor diameter had significant influence on the ozonization process; If the ratio was more than 10:1, the mass transfer state in bubble column would be worse because plunger flow appeared or liquid phase couldn抰 be mixed well. In addition, the orifice diameter of gas distributer had a significant influence on the process of annimaldehyde ozonization and had a less significant influence on the process of styrene ozonization. At the same time, According to the characteristics of gas-liguid phase reaction of ozone with annimadehyde, we investigated the influence of the three factors and the interaction of every two factors on the ozone mass transfer status, the mass fraction of annimaldehyde, reaction temperature, gas velocity of empty column, with cross design experiment. The result showed that the mass fraction of annimaldehyde and gas velocity of empty column had remarkable influence on the reaction conversion and reaction selectivity of annimaldehyde under our experimental conditions. The interaction between the mass fraction of annimaldehyde and gas velocity of empty column had also remarkable influence on reaction selectivity. There wasn1t significant influence on the ozone reaction by temperature and interaction I? between any other two factors. At last this dissertation had a tentative investigation on the terpene ozonization. The initial results showed that: (1) a inene ozonization was faster than 13 pinene in both polar-solvent ethanol and non-polar-solvent n-pentane, which was similar with the gas competitive ozonization between, a inene and P ? pinene. Moreover, in the...