The study on water electrolysis in the presence of ultrasonic field

• Main Authors: Chih-Hsuan Wang, 王智玄
• Other Authors: Lih-Wu Hong
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/53694154569883503589

碩士 === 國立中央大學 === 能源工程研究所 === 99 === As an energy carrier, hydrogen will play an important role in the future because of its high energy content per unit mass and it is cleaner than the chemical fuels. Today, water electrolysis is a developed technology that generates the purest hydrogen gas. However, it may cause high energy cost. Therefore, energy conservation becomes more and more important and is a major object in many researches. During the process of electrolysis, the electrode plate would be covered by bubbles resulting in the drag of the reactions and high overpotentials at the surface of electrodes. To abate this phenomenon, agitation would be added, and ultrasonic field would offer comparable effect. In this study, we will discover the influence of ultrasonic on electrolysis by 4 parameters such as concentration, voltage, frequency, and power. Each electrolysis treatment takes 600 seconds, data recorded by a potentiostat / galvanostat. The results of experiment show that in the condition of high current density, micro jet and stagnation flow circular produced by cavitation would remove bubbles on the electrode plate, and lower ohmic polarization effectively. The bulk of explosion of cavitation bubbles close to electrode plate will produce high temperature to accelerate reactive rate, and increase efficiency of chemical reaction. Finally, the maximum current density enhancement of the system is about 27%, for concentration 8M, voltage 5V, while an ultrasonic field (25kHz, 540W) is applied.