6533b7d4fe1ef96bd1262802
RESEARCH PRODUCT
Azo-Dyes Photocatalytic Degradation in Aqueous Suspension of TiO2 Under Solar Irradiation
Vittorio LoddoGiuseppe MarcìAlessandra Bianco PrevotVincenzo AugugliaroMarco PazziLeonardo PalmisanoElisa I. García-lópezClaudio BaiocchiSixto MalatoEdmondo Pramaurosubject
Environmental EngineeringPhotochemistryHealth Toxicology and MutagenesisPhotochemistryHeterogeneous catalysisCatalysisCatalysischemistry.chemical_compoundMethyl orangeEnvironmental ChemistryIrradiationColoring AgentsPhotodegradationTitaniumAqueous solutionBenzenesulfonatesPublic Health Environmental and Occupational HealthGeneral MedicineGeneral ChemistryPollutionchemistryTitanium dioxideSunlightPhotocatalysisIndicators and ReagentsAzo CompoundsOxidation-ReductionWater Pollutants Chemicaldescription
Abstract The photodegradation of two common and very stable azo-dyes, i.e. methyl-orange (C14H14N3SO3Na) and orange II (C16H11N2SO4Na), is reported. The photocatalytic oxidation was carried out in aqueous suspensions of polycrystalline TiO2 irradiated by sunlight. Compound parabolic collectors, installed at the “Plataforma Solar de Almeria” (PSA, Spain) were used as the photoreactors and two identical reacting systems allowed to perform photoreactivity runs for the two dyes at the same time and under the same irradiation conditions. The disappearance of colour and substrates together with the abatement of total organic carbon content was monitored. The main sulfonate-containing intermediates were found to be in lower number in respect to those obtained under artificial irradiation. In particular there were no more evidence of the presence of hydroxylated transients. The dependence of dye photooxidation rate on: (i) substrate concentration; (ii) catalyst amount; and (iii) initial pH was investigated. The influence of the presence of strong oxidant species (H2O2, S2O82−) and some ions (Cl−, SO42−) on the process was also studied.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2002-12-01 |