title: Ferrate(VI) as a greener oxidant: Electrochemical generation and treatment of phenol.
abstract: Ferrate(VI) (Fe(VI)O4(2-), Fe(VI)) is a greener oxidant in the treatment of drinking water and wastewater. The electrochemical synthesis of Fe(VI) may be considered environmentally friendly because it involves one-step process to convert Fe(0) to Fe(VI) without using harmful chemicals. Electrolysis was performed by using a sponge iron as an anode in NaOH solution at different ionic strengths. The cyclic voltammetric (CV) curves showed that the sponge iron had higher electrical activity than the grey cast iron. The optimum current density was 0.054mAcm(-2) in 10M NaOH solution, which is much lower than the electrolyte concentrations used in other electrode materials. A comparison of current efficiency and energy consumption was conducted and is briefly discussed. The generated ferrate solution was applied to degrade phenol in water at two levels (2mgL(-1) and 5mgL(-1)). The maximum removal efficiency was ∼70% and the optimum pH for phenol treatment was 9.0. Experiments on phenol removal using conventional coagulants (ferric chloride (FeCl3) and polyaluminium chloride (PAC)) were performed independently to demonstrate that removal of phenol by Fe(VI) occurred mainly by oxidative transformation. A combination of Fe(VI) and coagulant may be advantageous in enhancing removal efficiency, adjusting pH, and facilitating flocculation.
authors.affiliation: Chemical Engineering College, Northeast Dianli University, Jilin City 132012, People's Republic of China.
authors.forename: Xuhui
authors.initials: X
authors.lastname: Sun
authors.affiliation: Chemical Engineering College, Northeast Dianli University, Jilin City 132012, People's Republic of China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Chemical Engineering College, Northeast Dianli University, Jilin City 132012, People's Republic of China.
authors.forename: He
authors.initials: H
authors.lastname: Liang
authors.affiliation: Chemical Engineering College, Northeast Dianli University, Jilin City 132012, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Ying
authors.affiliation: Chemical Engineering College, Northeast Dianli University, Jilin City 132012, People's Republic of China.
authors.forename: Meng
authors.initials: M
authors.lastname: Xiangxu
authors.affiliation: Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, 1266 TAMU, College Station, TX 77843, USA. Electronic address: vsharma@sph.tamhsc.edu.
authors.forename: Virender K
authors.initials: VK
authors.lastname: Sharma
keywords: Coagulation; Ferrate; Oxidation; Removal; Sponge iron