Adsorption and catalytic oxidation of organic pollutants using Fe-zeolite

• Published in: Water science and technology Vol. 77; no. 3-4; pp. 939 - 947
• Main Authors: Russo, Analia V, Andrade, Cesar Velasco, De Angelis, Laura E, Jacobo, Silvia E
• Format: Journal Article
• Language: English
• Published: England IWA Publishing 01.02.2018
• Subjects: Adsorption; Aqueous solutions; Aromatic compounds; Aromatic hydrocarbons; Batch reactors; Benzene; Benzene - chemistry; Carbon; Catalysis; Catalysts; Catalytic oxidation; Experiments; Groundwater; Groundwater - chemistry; Groundwater treatment; Hazardous materials; Hydrocarbons; Hydrogen peroxide; Hydrogen Peroxide - chemistry; Hydrogen-Ion Concentration; Iron; Iron - chemistry; Kinetics; Leaching; Materials science; Nanoparticles; Oxidation; Oxidation-Reduction; Oxidizing agents; Permeable reactive barriers; pH effects; Phenols; Pollutants; Pollution prevention; Removal; Solutions; Surfactants; Toluene; Toluene - chemistry; Water Pollutants, Chemical - chemistry; Water Purification - methods; Xylene; Xylenes - chemistry; Zeolites; Zeolites - chemistry
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2017.611

In this work, a natural zeolite, modified and loaded with iron (NZ-A-Fe) as a heterogeneous catalyst, was characterized for its suitability as a permeable reactive barrier (PRB) material for treatment of aromatic hydrocarbons in groundwater. Adsorption and oxidation processes were analyzed. Batch adsorption tests for benzene, toluene and xylene (BTX) aqueous concentrated solutions were performed at neutral pH. Kinetic adsorption was described with the pseudo-second-order model. Experiments were performed using a stirred batch reactor with near 11 mM initial BTX concentration applying NZ-A-Fe as solid catalyst and H O as an oxidant. BTX removal reached 80% in 600 min in these experimental conditions. Catalytic oxidation was described with a pseudo-first-order kinetic model. No significant iron leaching was detected during all the experiences. These investigations show that coupling adsorption with catalytic oxidation with this novel system is a promising procedure to simultaneously remove BTX from moderately concentrated aqueous solution at neutral pH in groundwater.