Kinetics and mechanisms of As(III) oxidation by free available chlorine (FAC-the sum of HOCl and OCl-), ozone (O3), and monochloramine (NH2Cl) were investigated in buffered reagent solutions. Each reaction was found to be first order in oxidant and in As(III), with 1:1 stoichiometry. FAC-As(III) and O3-As(III) reactions were extremely fast, with pH-dependent, apparent second-order rate constant...

Photocatalytic oxidation/ozonation of a mixture eight pharmaceuticals added to secondary effluent, SE, an urban wastewater treatment plant has been studied using TiO2 supported on commercial Al2O3/SiO2 ceramic foams. As radiation source UVA LEDs (365 nm) or solar was used. Pharmaceuticals were at high (1 mg L−1 each) relatively low (50 μg concentration, contributing 25% and 1.5% the initial TOC...

A study was conducted on the efficacy of the system based on the simultaneous use of ozone and powdered activated carbon (PAC) in removing sodium dodecylbenzenesulphonate (SDBS) from drinking waters and on the influence of operational parameters (PAC dose, ozone dose and presence of radical scavengers [HCO3-]) on this process. Results obtained showed that low doses of PAC during SDBS ozonation ...

Four pharmaceuticals (ranitidine, nizatidine, doxylamine, and carbinoxamine) were selected as model compounds to assess the efficiency of four oxidants (ozone (O3), chlorine (Cl2), chlorine dioxide (ClO2) and potassium permanganate (KMnO4)) on the removal of amine-based pharmaceutical and personal care products (PPCPs), as well as the reduction of their N-Nitrosodimethylamine formation potentia...

Using sludge obtained from municipal sewage treatment plants, the response of viable bacterial populations during the sludge ozonation process was investigated by a combination of adenosine triphosphate (ATP) assay and propidium monoazide (PMA)-Miseq sequencing. The ATP assay was first optimized for application on sludge samples by adjusting the sludge solid contents and reaction time. PMA-modi...

Seven volatile organic chemicals (VOCs) on the EPA Contaminant Candidate List together with 1,1-dichloropropane were studied for their reaction kinetics and mechanisms with ozone and OH radicals during ozonation and the ozone/ hydrogen peroxide advanced oxidation process (O3/H2O2 AOP) using batch reactors. The three aromatic VOCs demonstrated high reactivity during ozonation and were eliminated...

The batik industry generates large amounts of highly colored wastewater. Azo dyes in wastewater can cause environmental pollution. In this study, synthetic containing 32 mg/L Reactive Black 5 (RB5) and Orange 16 (RO16) was treated by ozonation a 2 L batch reactor. color unit reduced from 4240 to 70 after 10 min below 50 15 (7.3 g O3/m3, 4 L/min). first-order decay constant for determined be 1.1...

The elimimation of mefenamic acid has been carried out by photolysis, ozonation, adsorption onto activated carbon (AC) and combinations of the previous single systems (O3+AC and O3+UV). The results obtained indicate that mefenamic acid is not photo-reactive, showing a relatively low quantum yield of the order of 6 x 10 mol Einstein. Application of ozone to mefenamic aqueous solutions instantane...

Activated carbon from pine cone (PCAC) was used as a precursor to prepare Fe3O4/magnetic activated carbon (MPCAC). Here, the removal of linear alkylbenzene sulfonate (LAS) was studied using catalytic ozonation process (COP) in exposure to MPCAC. Subsequently, it was compared with PCAC. Moreover, the effects of solution's initial pH, catalyst dosage, and the time of ozonati...