PERFORMANCE EVALUATION OF ELECTROLYTE CONCENTRATION AND OPERATING PARAMETERS FOR ENHANCED OXYHYDROGEN PRODUCTION VIA ALKALINE ELECTROLYSIS

Abstract

Oxyhydrogen (HHO) gas, produced through alkaline electrolysis, presents as an alternative fuel to curb Indonesia’s transportation-related emissions. This study evaluates the effects of potassium hydroxide (KOH) concentrations (5%-25%) and applied currents (5A-30A) on HHO productivity, electrolyte temperature, onset time to achieve a stable 2:1 composition ratio, cell efficiency, and verification of HHO gas composition. Results presented that HHO gas flow rate increased with increasing currents and KOH concentrations, peaking at 1.46 LPM at 20% KOH 30A, while the electrolyte temperature rose accordingly. The onset time for a stable 2:1 composition ratio decreased with increasing current and concentration, revealing a minimum of 5.7 minutes at 25% KOH and 20 A. Gas composition verification through GC-TCD closely matched real-time measurements at a condition of 10% KOH 5A, resulting in a similar 2:1 composition ratio. Maximum efficiencies are observed at moderate currents and concentrations, with diminishing returns observed at higher levels. Optimal operating conditions were defined as 5A for 5%-15% KOH, 10A for 20% KOH, and 5A for 25% KOH, based on peak efficiencies, temperature (<60°C), and the fastest onset time.