Optimization of physico-chemical parameters of hydrogen production by electrolysis of water

摘要

The present paper aims to determine the optimum physico-chemical parameters (input voltage, input amperage, cell temperature, electrolyte type and electrolyte concentration) for producing hydrogen by alkaline water electrolysis. Experiments were carried out in a water electrolysis cell using cathode alloy (Zn95%Cr5%)(mass%) already tested and proven its productivity in our previous work. The results clearly show that at a particular reaction conditions, an optimum amperage must be applied for each used voltage. For example for 4 Volts, the optimal value of amperage was 0,25 Amps whose the production of hydrogen was also optimal. In addition, a series of tests were conducted to test the effect of cell temperature. It was found that the increase in the electrolyte temperature raises the volume of gas until 32°C. Then the volume of hydrogen remains constant and recommences to increase at temperature higher than 47.5°C. Potassium hydroxide (KOH) was the best electrolyte tested in this study. The optimum concentrations recorded were 25g/1 for 4 Volts/0.25Amps and 30g/1 for 5Volts/0.3Amps at 25°C.