%0 Journal Article %J Water Research %D 2012 %T Kinetics and efficiency of H 2O 2 activation by iron-containing minerals and aquifer materials %A Pham, A.L.T. %A Doyle, F.M. %A Sedlak, D.L. %K Advanced Oxidation Processes %K aquifer %K Aquifer materials %K Aquifers %K Article %K bicarbonate %K catalyst %K Chemical %K chemical reaction %K chemistry %K citric acid %K clay %K decomposition %K Dissolved silica %K dithionite %K ecosystem restoration %K Efficiency %K Environmental Remediation %K Fenton reactions %K Ferric Compounds %K ferric ion %K ferric oxide %K Gain insight %K ground water %K Groundwater %K Groundwater resources %K Groundwater treatment %K Hydrogen peroxide %K Hydrogen-Ion Concentration %K hydroxyl radical %K in situ measurement %K Iron %K iron oxide %K Iron oxides %K Iron-containing catalyst %K Iron-containing clays %K Iron-containing minerals %K Kinetics %K Manganese %K Manganese Compounds %K manganese derivative %K Manganese oxide %K Manganese oxide coating %K Materials %K methodology %K mineral %K Minerals %K Mn content %K Oh yields %K Oxidation %K oxidation reduction reaction %K Oxidation-Reduction %K oxide %K Oxides %K pH %K phenol %K phenol derivative %K Phenols %K pollutant removal %K priority journal %K process optimization %K Protective coatings %K reaction kinetics %K Silica %K silicon dioxide %K Situ chemical oxidation %K soil pollutant %K Soil Pollutants %K stoichiometry %K United States %K waste component removal %K water pollutant %K Water Pollutants %K Water treatment %X To gain insight into factors that control H 2O 2 persistence and OH yield in H 2O 2-based in situ chemical oxidation systems, the decomposition of H 2O 2 and transformation of phenol were investigated in the presence of iron-containing minerals and aquifer materials. Under conditions expected during remediation of soil and groundwater, the stoichiometric efficiency, defined as the amount of phenol transformed per mole of H 2O 2 decomposed, varied from 0.005 to 0.28%. Among the iron-containing minerals, iron oxides were 2-10 times less efficient in transforming phenol than iron-containing clays and synthetic iron-containing catalysts. In both iron-containing mineral and aquifer materials systems, the stoichiometric efficiency was inversely correlated with the rate of H 2O 2 decomposition. In aquifer materials systems, the stoichiometric efficiency was also inversely correlated with the Mn content, consistent with the fact that the decomposition of H 2O 2 on manganese oxides does not produce OH. Removal of iron and manganese oxide coatings from the surface of aquifer materials by extraction with citrate-bicarbonate-dithionite slowed the rate of H 2O 2 decomposition on aquifer materials and increased the stoichiometric efficiency. In addition, the presence of 2 mM of dissolved SiO 2 slowed the rate of H 2O 2 decomposition on aquifer materials by over 80% without affecting the stoichiometric efficiency. © 2012 Elsevier Ltd. %B Water Research %V 46 %P 6454-6462 %G eng %U https://www.scopus.com/inward/record.uri?eid=2-s2.0-84868303803&doi=10.1016%2fj.watres.2012.09.020&partnerID=40&md5=de296bdabf6181c9d7c93b936e0fe754 %R 10.1016/j.watres.2012.09.020