Removal of chemical oxygen demand (COD) from hospital wastewater by electro fenton process using graphite–graphite electrochemical system

Removal of COD from hospital wastewater generated from Al- Diwaniyah hospital located in Iraq was achieved using graphite–graphite electro-Fenton (EF) system. The effect of various operational parameters on the COD removal efficiency was investigated based on response surface methodology (RSM). Optimal conditions were the current density of 20mA/cm2, FeSO4 concentration of, and time of  It achieved a COD elimination efficiency of 97.964 % at a specific energy consumption of 10.78 kWh/kg. The results indicated that time had the least effect on the efficiency with which chemical oxygen demand is eliminated, however, the share of current density had the greatest effect, followed by the FeSO4 concentration. The adequacy of the model equation was confirmed by its high R2 value (99.62%). The present study shows that the graphite–graphite EF system was an efficient tool for removing COD from hospital wastewaters.