TY - JOUR
T1 - Adsorptive removal of arsenic using a novel akhtenskite coated waste Goethite
AU - Shih, Yu Jen
AU - Huang, Re Lin
AU - Huang, Yao Hui
N1 - Funding Information:
The authors would like to thank the National Science Council of Taiwan , for financially supporting this research under Contract No. NSC 102-2917-I-564 -028 . Ted Knoy is appreciated for his editorial assistance.
Publisher Copyright:
© 2014 Elsevier Ltd. All rights reserved.
PY - 2015
Y1 - 2015
N2 - In recent years, the synthesis of manganese-based mixed oxides that can promote both the oxidation and the adsorption of arsenic has aroused great interest among those who are involved in management of arsenic wastewater. In this work, waste goethite, BT9 (α-FeOOH, 0.25-1 mm, 232 m2 g-1), which was recycled from industrial fluidized-bed Fenton equipment, was combined with akhtenskite (ε-MnO2), called MnBT9, for use in the adsorptive removal of arsenic (As(III) and As(V)) from solution. MnBT9 was prepared using a fluidized-bed reactor (FBR) in which ε-MnO2, formed by oxidizing Mn2 with sodium hypochlorite (NaOCl), was uniformly deposited onto BT9 support particles. Langmuir isotherms suggested that BT9 effectively adsorbed As(V) (28.25 mg g-1) but was mostly ineffective in adsorbing As(III) (8.03 mg g1). Nevertheless, the deposition of MnO2 on MnBT9 markedly increased its capacity to adsorb As(III) (34.36 mg g-1) without significantly influencing the retention of As(V) by the BT9 substrate. Kedge XANES (X-ray absorption near edge structure) analysis revealed that As(III) was totally oxidized to As(V) on MnBT9. A pseudo-second-order model was used to elucidate the kinetics of adsorption; at pH 3.5, MnBT9 removed As(III) at a higher rate than it removed As(V), proving that oxidation was a limiting step of arsenic removal when the BT9 substrate dominated the adsorption of As(V) in either its native form or formed by the oxidation of As(III).
AB - In recent years, the synthesis of manganese-based mixed oxides that can promote both the oxidation and the adsorption of arsenic has aroused great interest among those who are involved in management of arsenic wastewater. In this work, waste goethite, BT9 (α-FeOOH, 0.25-1 mm, 232 m2 g-1), which was recycled from industrial fluidized-bed Fenton equipment, was combined with akhtenskite (ε-MnO2), called MnBT9, for use in the adsorptive removal of arsenic (As(III) and As(V)) from solution. MnBT9 was prepared using a fluidized-bed reactor (FBR) in which ε-MnO2, formed by oxidizing Mn2 with sodium hypochlorite (NaOCl), was uniformly deposited onto BT9 support particles. Langmuir isotherms suggested that BT9 effectively adsorbed As(V) (28.25 mg g-1) but was mostly ineffective in adsorbing As(III) (8.03 mg g1). Nevertheless, the deposition of MnO2 on MnBT9 markedly increased its capacity to adsorb As(III) (34.36 mg g-1) without significantly influencing the retention of As(V) by the BT9 substrate. Kedge XANES (X-ray absorption near edge structure) analysis revealed that As(III) was totally oxidized to As(V) on MnBT9. A pseudo-second-order model was used to elucidate the kinetics of adsorption; at pH 3.5, MnBT9 removed As(III) at a higher rate than it removed As(V), proving that oxidation was a limiting step of arsenic removal when the BT9 substrate dominated the adsorption of As(V) in either its native form or formed by the oxidation of As(III).
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U2 - 10.1016/j.jclepro.2014.10.065
DO - 10.1016/j.jclepro.2014.10.065
M3 - Article
AN - SCOPUS:84923997487
VL - 87
SP - 897
EP - 905
JO - Journal of Cleaner Production
JF - Journal of Cleaner Production
SN - 0959-6526
IS - 1
ER -