Duangta KitkaewAthit PhetrakSumate AmpawongRachaneekorn MingkhwanDoungkamon PhihusutKamolnetr OkanurakChongrak PolprasertMahidol University. Faculty of Public Health. Department of Sanitary EngineeringMahidol University. Center of Excellence on Environmental Health and Toxicology (EHT)Mahidol University. Faculty of Tropical Medicine. Department of Social and Environmental MedicineMahidol University. Faculty of Tropical Medicine. Department of Tropical PathologyChulalongkorn University. Environmental Research InstituteThammasat University. Faculty of Engineering. Department of Civil Engineering2019-01-312019-01-312019-01-312018Environment and Natural Resources Journal. Vol. 16, No. 1 (2018), 91-100https://repository.li.mahidol.ac.th/handle/20.500.14594/40499Iron oxide particles (IOPs) were synthesized by chemical co-precipitation technique and further used as an adsorbent in removing hexavalent chromium (Cr(VI)) from aqueous solutions during batch adsorption. The IOP adsorbent had specific surface area of 65 m2/g, total pore volume of 0.25 cm3/g and mostly contained a mesoporous structure. The analysis of scanning and transmission electron microscopy indicated that the adsorbent contained a substantial amount of iron oxide of about 66%, which was well distributed throughout the adsorbent. The IOP adsorbent showed a rapid and efficient Cr(VI) removal that followed Langmuir adsorption isotherm model with maximum adsorption capacity of 2.39 mg-Cr(VI)/g-IOP, demonstrating a monolayer formation on the adsorptive sites of IOP. The kinetic adsorption of Cr(VI) on the IOP followed the pseudo-second-order model, suggesting chemisorption. Thus, the IOP adsorbent provides a potentially effective technology in eliminating of Cr(VI) from water since it can remove appreciable amounts of Cr(VI) with a relatively short contact time of 30 min.engMahidol UniversityHexavalent chromiumIron oxide particlesAdsorptionPseudo-second order modelResearch Article10.14456/ennrj.2018.9