Insights into solar photo-Fenton reaction parameters in the oxidation of a sanitary landfill leachate at lab-scale

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Tânia F. C. V. Silva (Author) FEUP; Rui Ferreira (Author) FEUP; Petrick A. Soares (Author) FEUP; Diego R. Manenti (Author) FEUP; Amélia Fonseca (Author) Other; Isabel Saraiva (Author) Other; Rui A. R. Boaventura (Author) FEUP; Vítor J. P. Vilar (Author) FEUP

Journal

Title: Journal of Environmental Management

Vol. 164

Pages: 32-40

ISSN: 0301-4797

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 23 Citations

ISI Web of Science

Scopus - 33 Citations

Scientific classification

FOS: Engineering and technology > Environmental engineering

CORDIS: Technological sciences > Technology > Environmental technology

Associated Projects

LSRE/LCM LA - RL1_P3 - Environmental Technologies

LSRE-LCM - Laboratório de Processos de Separação e Reação - Laboratório de Catálise e Materiais

Other information

Authenticus ID: P-00G-KS1

DOI: 10.1016/j.jenvman.2015.08.030

Abstract (EN): This work evaluates the effect of the main photo-Fenton (PF) reaction variables on the treatment of a sanitary landfill leachate collected at the outlet of a leachate treatment plant, which includes aerated lagooning followed by aerated activated sludge and a final coagulation-flocculation step. The PF experiments were performed in a lab-scale compound parabolic collector (CPC) photoreactor using artificial solar radiation. The photocatalytic reaction rate was determined while varying the total dissolved iron concentration (20-100 mg Fe2+/L), solution pH (2.0-3.6), operating temperature (10-50 degrees C), type of acid used for acidification (H2SO4, HCl and H2SO4 + HCl) and UV irradiance (22-68 W/m(2)). This work also tries to elucidate the role of ferric hydroxides, ferric sulphate and ferric chloride species, by taking advantage of ferric speciation diagrams, in the efficiency of the PF reaction when applied to leachate oxidation. The molar fraction of the most photoactive ferric species, FeOH2+, was linearly correlated with the PF pseudo-first order kinetic constants obtained at different solution pH and temperature values. Ferric ion speciation diagrams also showed that the presence of high amounts of chloride ions negatively affected the PF reaction, due to the decrease of ferric ions solubility and scavenging of hydroxyl radicals for chlorine radical formation. The increment of the PF reaction rates with temperature was mainly associated with the increase of the molar fraction of FeOH2+. The optimal parameters for the photo-Fenton reaction were: pH = 2.8 (acidification agent: H2SO4); T = 30 degrees C; [Fe2+] = 60 mg/L and UV irradiance = 44 Wuv/m(2), achieving 72% mineralization after 25 kJuv/L of accumulated UV energy and 149 mM of H2O2 consumed.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9