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研究生:蕭琤芳
研究生(外文):Hsiao, Jeng Fang
論文名稱:H為引發界面擾流促進氣/液吸收之研究:吸收液黏度和化學反應的影響
論文名稱(外文):Ehancement of Gas/Liquid Mass Transfer by the Artificially Provoked Interfacial Turbulence
指導教授:楊毓民楊毓民引用關係
指導教授(外文):C.Y.CHEN
學位類別:碩士
校院名稱:國立成功大學
系所名稱:化學工程學系
學門:工程學門
學類:化學工程學類
論文種類:學術論文
論文出版年:1998
畢業學年度:86
語文別:中文
論文頁數:74
中文關鍵詞:馬蘭果尼效應化學吸收黏度效應吸收促進
外文關鍵詞:Marangoni effectchemical absorptionviscosity effectEnhancement Factor
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氣體吸收程序中,跨越兩相界面間的質量傳送受界面狀態的影響很大。本
文主要探討人為引發界面擾流在一有利於吸收的情況和一不利於吸收的情
況下所扮演的角色。實驗是利用一個溢流式的吸收裝置,測定在有、無
Marangoni對流存在下氧氣的吸收速率。Marangoni對流是經由一毛細管將
具有低表面張力的純乙醇添加在支持液上所引發。本實驗所使用的支持
液(吸收液)為葡萄糖、甘油水溶液,目的是為了探討吸收液黏度的影響。
此外還選擇葡萄糖氧化酵素和白金觸媒添加於葡萄糖溶液中,與氧氣進行
發酵反應,目的是為了探討化學反應的影響。實驗結果顯示,以人為引發
的界面擾流促進純水吸收氧氣,吸收促進可達1.3,在黏度相當於純水5.5
倍的甘油水溶液,其吸收促進可達2.。而且當吸收液的黏度愈高,利用
Marangoni對流促進氣體吸收的效果愈佳。由實驗數據求得在沒有人為引
發的界面擾流時液相質傳係數與液體黏度的關係式為kL=4.87D1/2q1/6
m-0.32。存在有人為引發界面擾流的情況,則以Lu et al.(1996)建立的
質傳速率關聯式來描述高黏度液體對氧氣的吸收系統,結果顯示兩者會有
偏差存在,而且有黏度愈大偏差也愈大的趨勢,可見高黏度的效應於氧氣
的吸收系統中是不容忽略的。在化學反應的影響實驗,葡萄糖溶液添加酵
素和白金觸媒在本實驗系統中能有效的促進氣/液質傳。當溶液進行化學
吸收時,人為引發界面擾流並無有效的促進氣體吸收,且隨著化學反應造
成氣體吸收的速率加快,其效果愈不明顯。當加入的觸媒濃度低而剛開始
催化反應時,吸收的過程是擴散控制,因此吸收速率比較 小,而在此時
人為引發的Marangoni對流也較有效的促進吸收。當觸媒的濃度增大時反
應已快速的進行,因此吸收速率亦急速的增快,吸收的過程是反應控制,
在此時人為引發的Marangon對流促進的效果便不明顯。

In the processes of mass transfer across gas-liquid or liquid-
liquid interfaces, turbulence caused by gradients of density or
interfacial tension may occur. Under the condition that
advantages or that disavantages for gas absorption, the effect
of artificially induced Marangoni convection in the processe of
mass transfer is studied experimentally. In the present work,
the mass transfer coefficients were determined for the
absorption of O2 into solutions of different viscosities in the
presence and absence oThe experimental results reveal that mass
transfer rate of pure water with interfacial turbulence induced
by pure ethanol can be as mush as 1.3 times larger than that
without it, and the absorption enhancement is increased with the
increase of viscosity. A dimensionless equation for corelating
the experimental mass tranefer coefficient in the presence of
interfacial turbulence was satisfactorily developed.In the other
hand, experimental reaults show that chemical absorption with
enzyme and Pt catalyst can increase mass transfer rate
efficiently. However, in the process of chemical absorption,
interfacial turbulence did not increase the mass transfer
raterate and the absorption enhancement was decreased with the
increase of concentration of enzyme and Pt catalyst adding into
the solution. At the beginning of the chemical reaction, the
process of absorption is diffusion-controlled, so the absorption
rate is less than predict. At that time the experimental results
show more enhancement of the absorption by induced Marangoni
convection. When the reaction occuring rapidly the process of
absorption is reaction-controlled and the absorption rate is
also increased rapidly. At that time the experimental results
show less enhancement of the absorption by induced interfacial
turbulence.

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