Back to Search
Start Over
Photocatalytic degradation of industrial pulp and paper mill effluent using synthesized magnetic Fe 2 O 3 -TiO 2 : Treatment efficiency and characterizations of reused photocatalyst.
- Source :
-
Journal of environmental management [J Environ Manage] 2017 Feb 01; Vol. 187, pp. 298-310. Date of Electronic Publication: 2016 Dec 01. - Publication Year :
- 2017
-
Abstract
- In this work, heterogeneous photocatalysis was used to treat pulp and paper mill effluent (PPME). Magnetically retrievable Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> was fabricated by employing a solvent-free mechanochemical process under ambient conditions. Findings elucidated the successful incorporation of Fe <subscript>2</subscript> O <subscript>3</subscript> into the TiO <subscript>2</subscript> lattice. Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> was found to be an irregular and slightly agglomerated surface morphology. In comparison to commercial P25, Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> exhibited higher ferromagnetism and better catalyst properties with improvements in surface area (58.40 m <superscript>2</superscript> /g), pore volume (0.29 cm <superscript>3</superscript> /g), pore size (18.52 nm), and band gap (2.95 eV). Besides, reusability study revealed that Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> was chemically stable and could be reused successively (five cycles) without significant changes in its photoactivity and intrinsic properties. Additionally, this study demonstrated the potential recovery of Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> from an aqueous suspension by using an applied magnetic field or sedimentation. Interactive effects of photocatalytic conditions (initial effluent pH, Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> dosage, and air flow-rate), reaction mechanism, and the presence of chemical oxidants (H <subscript>2</subscript> O <subscript>2</subscript> , BrO <subscript>3</subscript> <superscript>-</superscript> , and HOCl) during the treatment process of PPME were also investigated. Under optimal conditions (initial effluent pH = 3.88, [Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> ] = 1.3 g/L, and air flow-rate = 2.28 L/min), the treatment efficiency of Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> was 98.5% higher than the P25. Based on Langmuir-Hinshelwood kinetic model, apparent rate constants of Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> and P25 were 9.2 × 10 <superscript>-3</superscript> and 2.7 × 10 <superscript>-3</superscript> min <superscript>-1</superscript> , respectively. The present study revealed not only the potential of using magnetic Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> in PPME treatment but also demonstrated high reusability and easy separation of Fe <subscript>2</subscript> O <subscript>3</subscript> -TiO <subscript>2</subscript> from the wastewater.<br /> (Copyright © 2016 Elsevier Ltd. All rights reserved.)
Details
- Language :
- English
- ISSN :
- 1095-8630
- Volume :
- 187
- Database :
- MEDLINE
- Journal :
- Journal of environmental management
- Publication Type :
- Academic Journal
- Accession number :
- 27914351
- Full Text :
- https://doi.org/10.1016/j.jenvman.2016.10.024