The transformation of hexabromocyclododecane using zerovalent iron nanoparticle aggregates
Journal
Journal of Hazardous Materials
Journal Volume
277
Pages
76-83
Date Issued
2014
Author(s)
Tso, C. P.
Abstract
Hexabromocyclododecane (HBCD), an emerging contaminant, is a brominated flame retardant that has been widely detected in the environment. In this study, nanoscale zerovalent iron (NZVI) aggregates are firstly used to treat HBCD and its removal under different geochemical conditions is evaluated. HBCD is almost removed from solutions by NZVI, with a kSA of 4.22×10-3Lm-2min-1. An increase in the iron dosage and temperature increases the removal rate. The activation energy for the removal of HBCD by NZVI is 30.2kJmol-1, which suggests that a surface-chemical reaction occurs on NZVI. HBCD is adsorbed on the NZVI surface, where electrons were transferred to HBCD, and consequently forms byproducts with less bromide. Three common groundwater anions decrease the reaction kinetics and efficiency of NZVI. The kobs of HBCD in the presence of anions is in the order: pure water >Cl->NO3-≒HCO3-. The inhibitory effect of these anions may be a result of the possible complexation of anions with the oxidized iron surface. The oxidized sites on NZVI and oxidized species of iron also contribute to the removal of HBCD by adsorption on NZVI from solutions. © 2014 Elsevier B.V.
Subjects
Adsorption; Debromination; Hexabromocyclododecane; Ions; Nanoscale zerovalent iron aggregates
SDGs
Other Subjects
Activation energy; Adsorption; Byproducts; Groundwater; Ions; Iron; Iron compounds; Nanotechnology; Reaction kinetics; Brominated flame retardants; Debromination; Emerging contaminant; Geochemical conditions; Hexabromocyclododecanes; Nanoscale zero-valent iron; Temperature increase; Zero-valent iron nanoparticles; Aggregates; anion; bromide; ground water; hexabromocyclododecane; nanoparticle; nanoscale zerovalent iron; unclassified drug; brominated hydrocarbon; flame retardant; hexabromocyclododecane; iron; metal nanoparticle; water pollutant; activation energy; adsorption; aggregate; anion; bromine compound; complexation; iron; organic pollutant; pollutant removal; reaction kinetics; transformation; adsorption; analytic method; aqueous solution; article; chemical reaction kinetics; chemical structure; debromination; electron transport; morphology; synthesis; waste component removal; chemistry; ecosystem restoration; isolation and purification; kinetics; oxidation reduction reaction; particle size; pH; procedures; surface property; time; water management; water pollutant; Kobus; Environmental Restoration and Remediation; Flame Retardants; Hydrocarbons, Brominated; Hydrogen-Ion Concentration; Iron; Kinetics; Metal Nanoparticles; Oxidation-Reduction; Particle Size; Surface Properties; Time Factors; Water Pollutants, Chemical; Water Purification
Type
journal article