REMOVAL OF AMMONIA FROM SOURCE-SEPARATED URINE BY ELECTROLYTIC OXIDIZATION USING RuO2-IrO2-TiO2/Ti ELECTRODES.

This study investigated the effects of current density and dilution rates on the removal of ammonia from artificial urine by electrolytic oxidization using titanium electrodes coated with ruthenium and iridium (RuO₂-IrO₂-TiO₂/Ti). With a total electrode area of 160 cm² dipped into 1.0 L urine, a current density of 50 mA cm^-2, and an electrolysis time of 180 min, 22.19% of ammonia was removed, and the energy consumption per unit of removed ammonia was found to be 56.90 kWh kg^-1. When urine was 10-fold diluted with tap water, removal efficiency and energy consumption were increased to 71.80 % and 500.75 kWh kg^-1, respectively. With increase of current density or dilution multiples, ammonia removal efficiency, energy consumption and removal rate increased while the current efficiency decreased. The reported ammonia removal followed pseudo-first-order kinetics. Hence, it can be concluded that electrolytic oxidization exhibited a potential to remove ammonia from source-separated urine through a de-central manner and a completely automated technique. [ABSTRACT FROM AUTHOR]