Exploring the intensifying effect of periodate/hydroxylamine oxidation process for the effective mineralization of textile dyes effluents with consideration of environmental matrices

Abstract

This study delved into the potential of periodate/hydroxylamine process (PI/HA) as an efficient method for the degradation and mineralization of textile dyes. The PI/HA process generates a range of reactive oxygen species (ROS), which can degrade organic pollutants. The effects of processing conditions, common minerals, organic components, including humic acid and surfactants, and various real environmental matrices, i.e. deionized water, seawater, natural mineral water and treated wastewater effluent, on the PI/HA process efficiency were examined. The results showed that the PI/HA process could remove over 50% of initial dyes concentration in just 10 s, with 80% removal achieved at 10 min using a PI/HA molar ratio of 1 (1.5/1.5 mM). Further adjustments could result in 100% removal in less than 5 min. The process efficiently abated organic matter, with total organic carbon (TOC) reductions exceeding 80% at 60 min and ~90% at 120 min. Radical scavengers showed that •OH played a dominant role (~76%), while 1O2 contributed to a lesser extent (~8.5%). The degradation was more efficient at lower pH, a higher PI to HA molar ratio. The process was unaffected by low concentrations of common mineral anions and surfactants. Higher degradation levels were observed in natural mineral water and seawater.