Hamadan University of Medical Sciences Avicenna Journal of Environmental Health Engineering 2423-4583 2 2 2015 04 01 Monitoring of pH, Oxidation-Reduction Potential and Dissolved Oxygen to Improve the Performance of Dimethyl Phthalate Removal From Aqueous Solutions 4206 4206 10.17795/ajehe-4206 EN Ali Reza Rahmani Mohammad Taghi Samadi Reza Shokoohi Hassan Zolghadr Nasab Journal Article 10.17795/ajehe-4206 2015 09 30 2015 12 07 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 (5 - 120minutes), pH (2 - 10), H2O2 concentration (0.01 - 1 mmol/L) nZVI content (0.01 - 0.5 g/L) and initial DMP concentration (2 - 50 mg/L)were also studied. It was found that, at optimum amounts (pH = 4, H2O2 concentration = 0.1 mmol/L, nZVI = 0.05 g/L, initial DMPconcentration = 2 mg/L, and contact time = 60 minutes), approximately 98% of the pollutant was removed. This process could treatDMP well from aqueous environments and can be introduced as a cheap and effective method.