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電解法除去硫化氫的程序日益受重視，因其可產生有用的硫和氫，且在純度及產率上
，均超越其他種程序，研究中曾嘗試利用鹼性溶液吸收硫化氫來電解，但因硫會附著
於電極表面鈍化而造成操作不便，故將有機溶劑加入系統中將硫溶解，使電極繼續反
應，如此便構成一兩相電化學系統．
本研究選擇兩種適合基本理論探討之電化學系統，以研究有機溶劑加入之影響．
一、RDE 系統，以一般鐵離子氧化還原反應為探討對象，並瞭解兩相系統中Levich方
程式的適用性及修正性．研究結果指出在加入定量之有機溶劑(20%)下，Levich 方程
式仍可適用，唯應將控制之表轉速（ω0）乘上1.1±0.02倍．此外，結果亦顯示界面
張力較小的水－有機系統如甲苯或苯，其質傳速率將會增加，而界面張力較大的水－
有機系統如正己烷或環己烷，其質傳速率不受影響．
二、平行板系統，除探討有機溶劑之影響外，並加入萃取之競爭反應，此研究以硫離
子氧化為對象，在理論模式上定義水相在極限電流操作下之質傳速率方程式： Km''★
(1-θ)C F/α與有機相之萃取速率方程式：Kd''★θ(C★-C S/β) 當操作達穩定狀態
時，設兩速率達平衡，可得一穩態之極限電流(I1(s)) ，當研究之參數包括兩相之流
速(Re'')與有機相之體積分率(Xd)．
Km''與Kd''可由實驗個別求出，實驗結果顯示：
Km''=7.044X10-5Re''1/3 Xd''18<Re''54．將此兩速率經驗式代入模式所得之 I1(s)與實
驗結果相比較，標準偏差在5%之內，此即證實本理論模式在萃取式電化學系統之可行
性．
兩相電化學反應系統的研究，目前已逐漸受到重視，本研究成果不僅可以解決硫化氫
之問題且所建立之模式可用來解釋兩相流動系統之質傳現象，如此，對後續研究類似
系統者可給予一遵循之方向，或對兩相系統之設計與最適化之研究上有所助益．
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Electrolytic method to remove hydrogen sulfide has been more and more
appreciated nowadays, because it can produce usable sulfur and hydrogen;
furthermore it has the purity percentage yield more excellent than any
other process. In the past studies, it had been tried to use alkaline
solution to absorb hydrogen sulfide for electrolysis. But the absorbed
sulfur on the electrode surface could passivate the electrode cause the
operation inconvenient. Therefore, here we added organic slovent to the
system and found that made the absorbed sulfur could be removed off from
the electrode and hence the reaction continuous. This constitutes a
two-phase electrochemical extractive process.
In this thesis, we choose two electrochemical systems to study the effect
of the organic solvent on the process. First , in the RDE system, the
mass-transter characteristics of a two-phase system formed by mixing a
fixed quantity (20v/v%) of organic slovent with an aqueous ferricyanide
electrolyte solution was studied. The Levich equation was found to be
applicable to the two-phase system with only a minor modification in the
angular velocity (ω) at Reynolds numbers between 3~5x104. The
experimental results indicate that the interfacial tension is the most
important variable for the twophase system. One group of organic solvents
with smaller interfacial tension, such as benzene or toluene, which was
observed to be 1.1±0.02 times the obseerved angular velocity. For the
other group with larger interfacial tension, such as n-hexane or
cyclohexane, there is no need to modify the observed angular velocity.
Second, in the parallel-plate electrode system, the masstransfer phenomena
between aqueous-organic phase and electode producing sulfur from sulfide
ion were studied. A kinetic model was developed and tested for the
electrochemical conversion and extraction process. Under steady-state
condition, the electrochemical reaction rate at limiting operation,
defined as Km''A/V(1-θ)C R/α is equal to the extraction rate, defined as
Kd''A/Vθ(C★-CS/β) for this extractive electrochemical system.
Experimental parameters included volume fraction (Xd) and fulid velocity
(u''). The mass transfer only a minor modification in the angular velocity
(ω)at Reynolds numbers between 3~5x104. The experimental results indicate
that the interfacial tension is the most important variable for the
two-phase system. One group of organic solvents with smaller interfacial
tension, such as benzene or toluene, which was observed to be 1.1±0.02
times the observed angular velocity. For the other group with larger
interfacial tension, such as n-hexane or cyslohexane, there is no need
modify the observed angular velocity.
Second, in the parallel-plate electrode system, the masstransfer phenomena
between aqueous-organic phase and electrode producing sulfur from sulfide
ion were studied. A kinetic model was developed and tested for the
electrochemical conversion and extraction process. Under steady-state
condition, the electrochemical reaction rate at limiting operation defined
as Km''A/V (1-θ)C R/α is equal to the extraction rate defined as Kd''A/V
θ (C★-C S/β) for this extractive electrochemical system. Experimental
parameters included volume fraction (Xd) and fulid velocity (u''). The mass
coefficients, Km'' and Kd'' were obtained as
Km'' =7.044 x 10-5 Re''1/3 (1.073 + 0.575 Xd - X2d) and Kd'' =5.15 x 10-4 Re''
1/3 Xd with a Reynolds numbers (Re'') between 18~54 and volume fraction
under 60% for this two phase solution. the kinetic model is verified by
the compared I1(s) values of experiment with the numerically calculated
values within a standard deviation of 5%.
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