| Summary: | 博士 === 國立成功大學 === 化學工程研究所 === 83 === In a preliminary study on the reaction between benzyl chloride
(BzCl) and sodium bromide with tetrabutylammonium bromide (Bu4
NBr) as a phase transfer catalyst, we found that a third liquid
phase with rich catalyst appeared and the reaction rate
constant increased sharply when the amount of Bu4NBr or NaBr
exceeded a critical value. The catalyst in such a tri-liquid-
phase catalysis (TLPC) system can be recovered and recycled
from the reaction system as easily as the immobilized solid
ctalyst in solid-liquid-liquid triphase catalysis system. The
advantages are incentives for further investigations regarding
the formation of the third liquid phase and its effects on
reaction mechanism and rate. Except the BzCl/NaBr reaction
system, in this dissert- ation we mainly investigate another
system of TLPC, the reaction of n-butyl bromide/sodium
phenolate (BuBr/NaOPh) with Bu4NBr as a catalyst. The
influencing factors explored include the kinds of organic
solvents and quaternary onium salts as well as the amounts of
salts and NaOH added. In many cases, a third liquid phase was
formed and some peculiar phenomena were observed. The
formation of third liquid phase and the occurrences of these
phenomena are elucidated based on the distribution of catalyst
between two or among three liquid phases and the concentration
of bases in the organic phase. The effects of these factors on
the reaction mechanism and reaction rate are also explained.
Several reaction mechanisms and rate expressions for TLPC
reaction system are proposed. The pseudo-first-order kinetic
models can be employed most cases. (omit)
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