A Study of the Effect of Chelating Agents on the Mass Transfer and Kinetic Behaviors of Heavy Metal Ions from Electrolytic Chelated Metal Solutions

• Main Authors: Chi Chung Lai, 賴啟中
• Other Authors: Young Ku
• Format: Others
• Language: zh-TW
• Published: 1993
• Online Access: http://ndltd.ncl.edu.tw/handle/19623057339488861443

博士 === 國立臺灣科技大學 === 化學工程研究所 === 81 === This study addresses the effects of solution pH and chelating agents on the electrodeposition of heavy metal ions from chelated metal solutions. The use of a small scale batch electrochemical reactor and rotating disk electrode method were carried out for the study of the mass transfer and kinetic behaviors of heavy metals from chelated metal solutions. For the batch electrochemical reactor operation, the effect of solution pH can improve the current efficiency but decrease the metal removal. However, the distribution of various metal species in the chelated metal solution may have influence on the characteristics of mass transport of chelated metal solution system and thus the calculated diffusion coefficients relationship compared with the experimental values were determined to describe the mass transfer properties of chelated metal solution system. These results showed that the free and chelated metal species may have different diffusion coefficients which may contribute separately to the observed overall diffusion coefficients of the chelated metal solution. The relevant kinetic parameters such as reaction order, rate constant, and equilibrium potential were measured for metal ion in the chelated metal solution. The predominant metal species was found to play a more important role in determining the mass transfer properties of the chelated solution. This may be an aid which handle the mass transfer and kinetic behaviors of metal ion of the chelated electrolytic solution systems. A porous packed bed electrochemical reactor was used for the study of the effects of solution pH and chelating agents on the metal removal of chelated metal solutions under the limiting current condition. Mass transfer coefficient relationships of this system was obtained for describing the effects of solution pH and flow velocity which could be referred to determine the height of a packed bed reactor.