Investigating the effects of operational parameters on the electrochemicaltreatment of water containing p-nitrophenol

Nitrophenols are widely used in the production of various chemical products but can posesignificant threats to ecosystems and human health when released into the environment. TheUnited States Environmental Protection Agency recognizes nitrophenols as priority organicpollutants due to their high toxicity, persistence, and bioaccumulation[۱-۲]. Electrochemicalmethods have shown high efficiency in mineralizing organic pollutants, with electrolysis beingthe most common and cost-effective technique for decomposing these pollutants in wastewater.Electrolysis is an advanced oxidation process facilitated by the hydroxyl radical, a strongoxidizer that helps remove organic molecules from water. Organic pollutants can be eliminatedduring electrolysis through direct electron transfer to the anode (direct electrolysis) or byreacting with oxidants produced through electromagnetic reactions, such as the hydroxyl radical(OH) generated during water discharge at the anode (indirect electrolysis) [۳].This study aims to provide an efficient technology for wastewater treatment and investigatethe key parameters of the electrolysis process. The research findings reveal that the reaction flowdirectly impacts the removal efficiency of p-nitrophenol (PNP), while the initial concentration ofthe pollutant and the pH of the solution have opposite effects. PNP decomposition is moreefficient in an acidic environment compared to alkaline and neutral conditions. The increasedefficiency in acidic conditions can be attributed to the enhanced production of H+ ions, resultingin the formation of H۲SO۴, a strong acid that improves pollutant decomposition. Conversely, athigher pH levels, the formation of polymer intermediate products hampers PNP degradation dueto interactions with the hydroxyl group.In conclusion, this study highlights the potential of electrolysis as an efficient technology forwastewater treatment. The findings contribute to a better understanding of nitrophenol removaland offer insights for the development of optimized treatment systems.

Keywords:

Electrolysis , Graphit , p-nitrophenol