Monitoring of pH, Oxidation-Reduction Potential and Dissolved Oxygen to Improve the Performance of Dimethyl Phthalate Removal From Aqueous Solutions

Since the process of heterogeneous Fenton is more complex and dynamic than the common Fenton process, control and onlinemonitoring is entirely vital for optimum operation of this system. This study was aimed to investigate the effects of pH, oxidationreductionpotential (ORP) and dissolved oxygen (DO) variations on dimethyl phthalate (DMP) removal from aqueous solutions usingthe heterogeneous Fenton process with nano zero-valent iron (nZVI). Parameters affecting the process like contact time (۵ - ۱۲۰minutes), pH (۲ - ۱۰), H۲O۲ concentration (۰.۰۱ - ۱ mmol/L) nZVI content (۰.۰۱ - ۰.۵ g/L) and initial DMP concentration (۲ - ۵۰ mg/L)were also studied. It was found that, at optimum amounts (pH = ۴, H۲O۲ concentration = ۰.۱ mmol/L, nZVI = ۰.۰۵ g/L, initial DMPconcentration = ۲ mg/L, and contact time = ۶۰ minutes), approximately ۹۸% of the pollutant was removed. This process could treatDMP well from aqueous environments and can be introduced as a cheap and effective method.