Simultaneous photoreductive removal of copper (II) and selenium (IV) under visible light over spherical binary oxide photocatalyst

Aman, Noor; Mishra, Trilochan; Hait, Jhumki; Jana, Rajkumar

doi:10.1016/j.jhazmat.2010.11.001

Cited by 56 publications

(16 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In this regard, an earlier work on TiO 2 photocatalytic reduction of selenium oxyanions was carried out by Kikuchi et al [23] Since then, these systems have been examined by several other groups. [24][25][26][27][28][29][30][31][32][33][34][35][36] Many of these studies have also investigated the role of hole (h + ) scavengers such as formic acid during TiO 2 -assisted photocatalytic reduction of selenite and selenate and report significant removal of selenium contamination from the aqueous phase. [24][25][26][27][28] Recently, Aman et al [36] also reported using a modified Ti-Zrbased photocatalyst and EDTA (as a hole scavenger) for selenite/selenate removal from the aqueous phase.…”

Section: Introductionmentioning

confidence: 99%

Photocatalytic removal of selenite and selenate species: effect of EDTA and other process variables

Labaran

Vohra

2013

Environmental Technology

View full text Add to dashboard Cite

TiO2-assisted photocatalysis was employed for the removal of aqueous phase selenite and selenate species in conjunction with EDTA as a hole (h+) scavenger. Findings from the binary selenite/EDTA and selenate/EDTA systems showed high selenite and selenate removal at pH 4 and pH 6, with faster removal kinetics noted for the selenite species compared with the selenate species that showed a gradual change over the reaction course. The noted removal of selenite and selenate was attributed to their reduction by the conduction band electrons (e-). The effect of pH studies indicated high selenite, selenate, and EDTA removal in the acidic pH range, with the following specific trend: pH 4 > pH 6 > pH 12. Different from the EDTA studies, the use of thiocyanate alone did not initiate reduction of selenium oxyanions, and hence, its role as a hole scavenger in the present systems was not evident. However, the addition of EDTA to respective selenite/selenate/thiocyanate system at pH 4 did yield near complete removal of selenite and selenate species. The marginal role of thiocyanate as a hole scavenger was attributed to its negligible adsorption onto TiO2 surface. Furthermore, at pH 4 and within 3 h reaction time, enhanced selenate removal was noted with an increase in its initial concentration from 20 to 100 ppm, with near complete selenate removal noted for both cases. In general, findings from the present work indicate that both selenite and selenate can be successfully removed from the aqueous phase employing the TiO2-mediated photocatalysis and h(+)-scavenging agent EDTA.

show abstract

Section: Introductionmentioning

confidence: 99%

Photocatalytic removal of selenite and selenate species: effect of EDTA and other process variables

Labaran

Vohra

2013

Environmental Technology

View full text Add to dashboard Cite

show abstract

“…The powder and thin film properties were characterized in terms of: the Fourier transform infra-red (FTIR), the X-ray diffraction (XRD), UV-vis spectroscopy, atomic force microscopy (AFM).The secmiconductors association and the films homogeneity limit the electron-hole recombination, resulting in good efficiency in dyes photo degradation even under vsisible light irradiation. Aman and coworkers 8 studied waste water of copper mines and copper processing plant. Simultaneous photoreductive removal of copper (II) and selenium (IV) is studied for the first time using spherical binary oxide photocatalysts under visible light from a single contaminant, EDTA is found to be the best for Cu(II) reduction whereas formic acid is the best for Se(IV) reduction.…”

Section: Photocatalystmentioning

confidence: 99%

“…Byproducts and other inorganic ions were transfered into resin phase. Nano-ZnO photocatalyst can be regenerated and reused.Aman et al 26 …”

Section: Photocatalystmentioning

confidence: 99%

“…They were found to be active photocatalysts for evolution of hydrogen energy from water in the presence of sacrificial agent under visible light illumination. The textual properties (high surface area, narrow pore size, large pore volume and mesoprosity), visible light active band gap energy 1.90 eV and small practical size (47.95nm) collectively contribute for high hydrogen production ability.Aman et al 33 studied waste water of copper mines and copper processing plant contains both copper and selenium ions with other contaminants. In this paper simultaneous photoreductive removal of copper (II) and selenium (IV) is studied for the first time using spherical binary oxide pohotocatalyst under visible light.…”

Section: Photocatalystmentioning

confidence: 99%

See 1 more Smart Citation

Applications of Metal/Mixed Metal Oxides as Photocatalyst: A Review

Arora¹,

Jaswal²,

Singh³

et al. 2016

Orient. J. Chem

View full text Add to dashboard Cite

show abstract

“…Hence considering the adverse effects posed by selenium pollution and respective stringent regulatory limits, there is a need for a suitable treatment method. Several innovative technologies including photocatalytic degradation (PCD) process have been investigated for this purpose . For example, Kikuchi carried out an earlier work on TiO 2 photocatalytic reduction of selenate employing UV lamp as the energy source , and since then many studies have reported successful removal of aqueous phase selenite and selenate species by utilizing various ( h + ) scavengers using the above mentioned technology .…”

Section: Introductionmentioning

confidence: 99%

Solar Photocatalytic Removal of Selenite, Selenate, and Selenocyanate Species

Labaran

Vohra

2017

CLEAN Soil Air Water

View full text Add to dashboard Cite

Selenium release into aqueous environment because of increased anthropogenic activities and its adverse effects onto human and animal health have initiated stringent selenium drinking water and wastewater discharge regulations. Though typically selenite (SeO 3 2À ) and selenate (SeO 4 2À ) account for most selenium species in selenium contaminated water bodies however selenocyanate (SeCN À ) is another dominant selenium form in specific industrial effluents including those from petroleum refineries, mining, and power plants using fossil fuels. The present study investigated the potential of solar photocatalytic degradation (SPCD) process employing titanium dioxide (TiO 2 ) as photocatalyst and ethylenediaminetetraacetic acid (EDTA) as a hole scavenging agent, for the removal of selenite, selenate, and selenocyanate species from aqueous phase. The experimental results indicated pH 4 to be the optimum for highest selenium removal. Furthermore, solar energized photocatalytic removal of selenite, selenate, and selenocyanate increased with an increase in both initial selenium and initial EDTA concentrations. Though selenite and selenate can be reduced directly to elemental selenium, selenocyanate is removed via a two steps process, i.e., SeCNcomplex destruction followed by stepwise oxidation to selenite/selenate and then reduction to elemental selenium. Furthermore modeling results for selenocyanate removal using the response surface methodology and Box-Behnken design method are also presented. In general, solar photocatalysis is a promising technology that can successfully remove the aforementioned selenium species from aqueous phase with a careful adjustment of process variables.

show abstract

Simultaneous photoreductive removal of copper (II) and selenium (IV) under visible light over spherical binary oxide photocatalyst

Cited by 56 publications

References 33 publications

Photocatalytic removal of selenite and selenate species: effect of EDTA and other process variables

Photocatalytic removal of selenite and selenate species: effect of EDTA and other process variables

Applications of Metal/Mixed Metal Oxides as Photocatalyst: A Review

Solar Photocatalytic Removal of Selenite, Selenate, and Selenocyanate Species

Contact Info

Product

Resources

About