Importance of reagent addition order in contaminant degradation in an Fe(ii)/PMS system

Abstract

Reagent addition order has a significant effect on the contaminant degradation process in an Fe(II)/PMS system.

Using Pre-Oxidation Technique to Minimize Disinfection by-Products in Surface Water Treatment

“…Our findings are compatible with (Huang et al, 2016) who expressed that in acidic conditions, the degradation rate was enhanced markedly as the solution pH in the range 3.5 -5 while decreased considerably as the pH of the solution between 6 -8.4 (Huang et al, 2016). Farren, (2003) stated that THMs formation depends on several factors.…”

Both degradation and AOX accumulation are significantly enhanced in UV/peroxymonosulfate/4-chlorophenol/Cl− system: two sides of the same coin?

“…Recently sulfate radical-based Advanced Oxidation Processes (AOPs) are attracting much attention in degrading recalcitrant organic pollutants due to its strong oxidizing capacity (E ¼ 2.5-3.1 V versus NHE) and longer half-time (30-40 ps) of sulfate radical (SO 4 c À ). 1 Peroxymonosulfate (PMS) is known as an efficient precursor of SO 4 c À production, with assistance of transition metals, [2][3][4][5] heat, 6,7 base, 8,9 ultrasound, 10 carbon catalysts, 11,12 microwave 13 and ultraviolet (UV). [14][15][16] Upon the cleavage of the peroxo bond, PMS photolyzed by UV was suggested to produce SO 4 c À and cOH in a benign and economic way.…”

Efficient Degradation of Refractory Organics Using Sulfate Radicals Generated Directly from WO3 Photoelectrode and the Catalytic Reaction of Sulfate

“…Active species resulting in the catalytic oxidation of MO was identified. In addition, the practical ability of the photoelectrochemical system to yield active persulfate (S 2 …”

“…A reasonable schematic mechanism for efficiently removing MO using a WO 3 electrode in a PEC system is shown in Figure 6. The production of S 2 (8) and (9) HSO4 − in the case of low pH, which accelerates the reaction between sulfate radical and organic compounds.…”

“…Recently, S 2 O 8 2− has received intense scrutiny in water purification and soil remediation since the activation of S 2 O 8 2− is one of the most effective methods of producing sulfate radical (SO 4 − •) for the degradation of organic waste [2]. SO 4 − • with one unpaired electron has a high oxidation potential of 2.6~3.2 V vs. the normal hydrogen electrode (NHE), and more importantly has a longer lifetime (30-40 µs) than hydroxyl radical (HO•), so it is highly active to react with various contaminant, causing either partial or complete mineralization [3][4][5].…”