title: Sulfurized limonite as material for fast decomposition of organic compounds by heterogeneous Fenton reaction.
abstract: Rapid decomposition of wastewater contaminants using sulfurized limonite (S-limonite) was investigated. Limonite is used for desulfurization of biogases, and S-limonite is obtained from desulfurization plants as solid waste. In this work, the profitable use of S-limonite in water treatment was examined. The divalent Fe in S-limonite was expected to produce OH radicals, as Fe(2+) ions and limonite thermally treated with H2 do. Methylene blue was used for batch-wise monitoring of the decomposition performance. The decomposition rate was fast and the methylene blue solution color disappeared in only 10s when a small amount of H2O2 was added (1mM in the sample solution) in the presence of S-limonite. The OH radicals were formed by a heterogeneous reaction on the S-limonite surface and Fenton reaction with dissolved Fe(2+). The decomposition of pentachlorophenol was also examined; it was successfully decomposed in batch-wise tests. The surfaces of limonite before sulfurization, S-limonite, and S-limonite after use for water treatment were performed using scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that S-limonite reverted to limonite after being used for water treatment.
authors.affiliation: Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan. Electronic address: todakei@sci.kumamoto-u.ac.jp.
authors.forename: Kei
authors.initials: K
authors.lastname: Toda
authors.affiliation: Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Tsuda
authors.affiliation: Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ban
authors.affiliation: Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Edwin P
authors.initials: EP
authors.lastname: Koveke
authors.affiliation: Department of Chemistry and Biochemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Koinuma
authors.affiliation: Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Ohira
mesh_terms: D004396:Coloring Agents / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006862:Hydrogen Sulfide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008751:Methylene Blue / Q000737:chemistry*; D010416:Pentachlorophenol / Q000737:chemistry; D013455:Sulfur / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; D005290:Ferric Compounds; D014874:Water Pollutants, Chemical; C021024:ferric hydroxide; D013455:Sulfur; D006861:Hydrogen Peroxide; D010416:Pentachlorophenol; D008751:Methylene Blue; D006862:Hydrogen Sulfide
keywords: Heterogeneous Fenton reaction; Hydrogen sulfide; Limonite; Methylene blue; Pentachlorophenol