title: Removal of As(V) and As(III) by reclaimed iron-oxide coated sands.
abstract: This paper aims at the feasibility of arsenate and arsenite removal by reclaimed iron-oxide coated sands (IOCS). Batch experiments were performed to examine the adsorption isotherm and removal performance of arsenic systems by using the IOCS. The results show that the pH(zpc) of IOCS was about 7.0 +/- 0.4, favoring the adsorption of As(V) of anion form onto the IOCS surface. As the adsorbent dosage and initial arsenic concentration were fixed, both the As(V) and As(III) removals decrease with increasing initial solution pH. Under the same initial solution pH and adsorbent dosage, the removal efficiencies of total arsenic (As(V) and As(III)) were in the order as follows: As(V)>As(V)+As(III)>As(III). Moreover, adsorption isotherms of As(V) and As(III) fit the Langmuir model satisfactorily for the four different initial pH conditions as well as for the studied range of initial arsenic concentrations. It is concluded that the reclaimed IOCS can be considered as a feasible and economical adsorbent for arsenic removal.
authors.affiliation: Institute of Engineering Science and Technology, Department of Safety Health and Environ. Eng., Kaohsiung First University of Science and Technology, Kaohsiung, Taiwan.
authors.forename: Jia-Chin
authors.initials: JC
authors.lastname: Hsu
authors.forename: Chien-Jung
authors.initials: CJ
authors.lastname: Lin
authors.forename: Chih-Hsiang
authors.initials: CH
authors.lastname: Liao
authors.forename: Shyi-Tien
authors.initials: ST
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D001151:Arsenic / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D011791:Quartz / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D005290:Ferric Compounds; D014874:Water Pollutants, Chemical; D011791:Quartz; C000499:ferric oxide; D001151:Arsenic