Investigating sono-electrolysis for hydrogen generation and energy optimization
Yew Heng Teoh, S. L. Liew, Heoy Geok How, Haseeb Yaqoob, Mohamad Yusof Idroas, Muhammad Ahmad Jamil, Saad Uddin Mahmud, Thanh Danh Le, Hafız Muhammad Ali, Muhammad Wakil Shahzad
Abstract
Hydrogen (H 2 ) is expected to be the new fuel generation, surpassing conventional fossil fuels and coal in reducing carbon emissions. However, green H 2 production constitutes only a minor part of the H 2 production sector. Water electrolysis is a method for green H 2 production but suffers from low energy efficiency. Auxiliary ultrasound in H 2 production is a method under research for increasing H 2 production and energy efficiency. This study evaluates the effectiveness of H 2 production with auxiliary ultrasound under various parameters of temperature (28–45 °C), solution concentration (15–45 %), voltage (3.5–10 V), and ultrasound power (silent, low, and high) for electrolysis and sono-electrolysis. The result shows that sono-electrolysis benefits from increased H 2 production compared to electrolysis when voltage, temperature, solution concentration, and ultrasound power increase. However, the energy efficiency for sono-electrolysis is lower than that for electrolysis under all conditions due to inefficient ultrasound power transmitted and low H 2 production increase with ultrasound power. The H 2 production for electrolysis reaches an optimum condition at 129.5 cm 3 /h with an energy efficiency of 13.15 %, while high-power sono-electrolysis produces H 2 at 265 cm 3 /h with an energy efficiency of 7.71 % at the optimum condition. Ultrasound increases H 2 production in electrolysis but reduces energy efficiency. A more detailed exploration of electrolysis and sono-electrolysis is still needed to achieve high H 2 production with high energy efficiency.