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本文的主要目的乃研究二相系統中，在相轉移觸媒及氧化還原媒子作用下，間接電解
氧化苯甲醇。內容包括在相轉移觸媒催化下，以次氯酸根氧化苯甲醇之動力學，以及
在相轉移觸媒及氧化還原媒子(Redox mediator)作用下，間接電解氧化苯甲醇之機構
與動力學。並利用相轉移觸媒將水相無機氧化劑離子傳道至有機相作為有機相中之氧
化劑，提高氧化劑在有機相中之濃度，促進反應速率。本研究系統所用之相轉移觸媒
選擇高交辦且經濟的四級銨鹽與回收容易之固體相轉移觸媒。氧化態的媒子在有機相
中與有機物進行氧化反應，而且又可在電極表面上再生，本文選擇氧化力適中，應用
很廣，且高效率之cl-/OCl-為氧化還原媒子。探討在兩相間利用相轉移觸媒及氧化還
原媒子，間接電解氧化有機物之反應模式。
相轉移觸媒催化下，以次氯酸根為氧化劑氧化苯甲醇之兩相反應系統中，次氯酸根被
相轉移觸媒萃取至有機相中形成離子對，並在有機相中與苯甲醇進行氧化，其反應機
構如下：
（圖表省略）
在相轉移觸媒催化反應系統中，從水相萃取氧化劑至有機相是有相氧化系統相當重要
的步驟之一。由於氧化劑次氯酸根均伴隨著氯離子的存在，所以高純度的次氯酸鹽極
難獲得，因此本文探討在氯離子與次氯酸根離子共同存在下，以相轉移觸某萃取次氯
酸根至有機相中的模式，其萃取平衡式如式(A-1) 至(A-2)與(A-4)至(A-5) 組合而成
。結果為
（圖表省略）
其中Q+為移觸媒陽離子，K2為Q+OCl-在兩相間之分配係數，S為
（圖表省略）
其中K4為Q+Cl- 在兩相間之分配係數，K1與K3分別為OCl-與Cl-在水相與Q+之結合常
數。在20℃時，K1至K4之值分別為0.05M-1,17.4,0.004m-1 與87.7。
由實驗結果發現，無機離子與相轉移觸媒陽離子在水相中大都以游離態存在，在有機
相中大都以離子對型式存在。當水相的氯離子濃度及相轉移觸媒的濃度固定時，有機
相中次氯酸根與相轉移觸媒離子對的濃度倒數與水相內次氯酸根離子濃度的倒數成線
性關係。由實驗結果得知，以四丁基銨氯為相轉移觸媒，將次氯酸根從水相萃取至有
機相，二氯甲烷，之焓變化為8.60kcal/mol。
實驗結果發現，式(A-3) 反應式之次氯酸根相轉移觸媒離子對苯甲醇皆為一階反應，
且反應速率常數，K5，之頻率常數為2.23x 109M-1min-1 及其的活化能為10.4
kcal/mol，其速率式如下，
（圖表省略）
由實驗結果顯示當攪拌速率大於500rpm時，反應速率即不受質量傳道之影響，且在苯
甲醇率轉化小於91% 下，苯申醛選擇率可達100%。
利用媒子以及相轉移觸媒在兩相系統間接電解氧化苯甲醇之結果顯示，當以0.05M
BU4NHSO4為相轉移觸媒且攪拌速率小於500rmp時質傳效應不可忽略，當攪拌速率大於
500rpm時速率決定為電極表面氧化氯離子。其反應機構為陽極將還原態之媒子，Cl-
，氧化成氧化態之媒子，OCl-，利用相轉移觸媒傳道至有機相並氧化苯甲醇。陽極氧
化氯離子為氯分子及其水解機構如下，
（圖表省略）
次氯酸根被相轉移觸媒萃取至有機相，並進行氧化反應其機構如式(A-1) 至(A-5) 所
示。在此電解系統，影響電流效率的主要因素有pH值，溶劑之種類及相轉移觸媒之種
類及其濃度，但是電流密度與溫度的影響較小。
在相轉移觸媒與氧化還原媒子的作用下，探討二相系統間接電解氧化苯甲醇的動力學
，由理論的分析及實驗結果顯示，以石墨為陽極，在電極表面上電解還原態媒子，
Cl-，成氧化態之媒子，OCl- ，為一次反應。電極表面上氧化氯離子的電荷轉移係數
及交換電流密度，亦由實驗獲得。比較理論分析及實驗結果發現在兩相間接電解氧化
苯甲醇系統中，當有機相─水相之體積比為0.5,1.0 及2.0 時其電極表面水相之覆蓋
率分別為0.89,0.61 以及0.23。
利用自製高分子相轉移觸媒及氧化還原媒子，Cl-/OCl-，於兩相系統，間接電解氧化
苯甲醇。實驗結果顯示自製固體相轉移觸媒之高分子擔體的交鏈度愈小且氯甲基苯乙
烯的比例愈高，所得觸媒的活性基，三丁基磷，濃度愈大。且當攪拌速率大於400rpm
時，電流效率即不受質傳之影響。在此系統，產物苯甲醛電流效率的影響因素以觸媒
的特性、pH值、苯甲醇濃度以及觸媒用畢的影響較大。水溶液中氯離子濃度、溫度等
因素之影響較不顯著。
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The kinetics of the oxidation of benzyl alcohol by the hypochlrite, and
the mechanism and the kietics of the anodic oxidation of benzyl alcohol in
the presence of both redox mediator and phase-transfer catalyst were
studied in this dissertation.
The hypochlorite and chloride ions were shuttled between the organic and
aqueous phases which enhanced the concentration of hypochlorite ion in the
organic phase by the phase transfer catalyst. Therefore, the reaction rate
of the oxidation of benzyl alcohol in the organic phase significantly
increased when the phase transfer catalyst was used in this system. Both
the effective quaternary ammonium salt and polymer supported
phase-transfer catalysts were used as the phase transfer catalyst in this
studied.
In the presence of redox mediators, both the mechanism and kinetics of the
anodic oxidation of organic substance could be changed. The oxidizing
mediator reacted with organic substance in the bulk solution and became
reducing mediator which could be regenerated in-situ on the anode. The
Cl-/OCl- were used as redox mediator in this work due to the hypochlorite
was a mild and effective oxidant.
Under phase-transfer catalysis conditions, the quaternary ammonium
hypochlorite ion pair was extraction from the aqueous phase into the
organic phase where the oxidation of benzyl alcohol took place. The
reaction mechanisms were described as follow:
（圖表省略）
The extraction of hypochlorite ion from the aqueous phase into the organic
phase was one of the key steps in the oxidation of benzyl alcohol in the
two-phase reaction system. The equilibrium equations of the extraction of
hypochlorite ion from the aqueous phase into the organic phase was
described in Equations (A-1) to (A-2) and (A-4) to (A-5), and the model
was obtained by both the theoretical analysis and the experimental
results
（圖表省略）
where Q+ was the phase transfer catalyst cation, K2 was the distribution
coefficient of Q+OCl- in the two-phase system, and S was
（圖表省略）
where K4 was the distribution coefficient of Q+OCl- in the two-phase
system, K1 and K3 were the association constants of OCl- and Cl- with Q+,
respectively. At 20℃, The yalues of K1 to K4 were obtained to be 0.05
M-1, 17.4, 0.004 M-1 and 87.7, respectively.
The plot of the reciprocal of the concentration of quaternary ammonium
hypochlorite ion pair in the organic phase and the reciprocal of the
concentration of chloride ion in the aqueous phase was a straight line
when the concentrations of quaternary ammonium salt and chloride ion in
the aqueous phase were constant. The free energy of the extraction of
hypochlorite ion from the aqueous phase into the organic phase,
dichloromethane, in the presence of tertabutylammonium chloride as phase
transfer catalyst was obtained to be 8.60 Kcal/mol.
The reaction orders of the quaternary ammonium hypochlorite ion pain in
the organic phase and benzyl alcohol in Equation (A-3) were obtaimed to be
unity, respectively, Using tetrabutylammonium chloride as phase transfer
catalyst, the preexponential factor and the activation energy of the
reaction constant, k5, were obtained to be 2.23x109 M-1 min-1 and 10.4
Kcal/mol. The rate equation was
（圖表省略）
The results showed that the oxidation of denzyl alcohol in two immiscible
aqueous and dichloromethane phases was reaction controlled and located in
the organic phase when the stirring rate was larger than 500 rpm. The
experimental results also revealed that the selectively of benzaldehyde
was 100% when the conversion of benzyl alcohol was less than 91%.
The anodic oxidation of benzyl alcohol in the a two-phase system
containing both the redox mediator, Cl-/OCl-, and a phase transfer
catalyst had been studied. The reaction mechanism was proposed and the
factors which affected the current efficiency of producing benzaldehyde
were explored. The experimental results showed that the rate determining
step shifted from the shuttling rate of the redox ions between the
interface to the anodic oxidation of Cl- on the surface of anode when the
stirring rate changed from 400 to 500 rpm in the presence of 0.05 M
Bu4NHSO4. The results also revealed that benzyl alcohol was mainly
oxidized in the organic phase by the way of shuttling Cl-/OCl- mediator.
The mechanism of the anodic oxidation of chloride ion and the hydrolysis
of chlorine in the aqueous phase was
（圖表省略）
The hypochlorite ion was extracted from the aqueous phase to the organic
phase and reacted with benzyl alcohol in the presence of phase-transfer
catalyst, as described in Equations (A-1) to (A-5).
The current efficiency was mainly governed by the pH value and the nature
of the organic solvent as well as the types and the concentration of phase
transfer catalyst and slightly affected by both the current density and
temperature.
The kinetics of the anodic oxidation of benzyl alcohol in the two-phase
systeminvolving both, the redox mediator, Cl-/OC-, and a phase transfer
catalyst were investigated. The reaction order of the anodic oxidation of
chloride ion in the aqueous phase was unity. The charge-transfer
parameters and the exchange current density of the anodic oxidation of
chloride ion in the aqueous phase were obtained. The theoretical
calculations correlated well with the experimental data. The fractions of
the anodic surface covered by the aqueous phase were evaluated to be 0.89,
0.61, and 0.23 when the organic-to-aqueous volume ratios were 0.5, 1.0,
and 2.0, respectively.
Using polymer-supported phase transfer catalyst and redox mediator,
Cl-/OCl-, the anodic oxidation of benzyl alcohol was also studied. The
experimental results revealed that decreasing the crosslinking and
increasing the content of chloromethylstyrene in the polymer supports, the
concentration of phase transfer active site, tri-n-butylphosphine,
increased. In this system, the anodic oxidation of benzyl alcohol was
reaction controlled when the stirring rate was greater than 400 rpm. The
experimental results also showed that the current efficiency of the anodic
oxidation of benzyl alcohol was mainly affected by the characteristics and
the weight of polymer-supported phase transfer catalyst, pH value, and the
concentration of benzyl alcohol. The concentration of chloride and
temperature were slightly affected the current efficiency.
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