Heterogeneous Fenton Reaction

Fujihira M, Satoh Y, OsaT. Heterogeneous photocatalytic reactions on semiconductor materials. III. Effect of pH and Cu2+ ions on the photo-Fenton type reaction. Bull Chem Soc Jpn 1982 55 666-71. 

Rusevova, K., Koferstein, R., Rosell, M., Richnow, H.H., Kopinke, F.D., and Georgi, A. (2014) LaFeOs and BiFeOs perovsldtes as nanocatalysts for contaminant degradation in heterogeneous Fenton-like reactions. Chem. Eng. / 239, 322-331. 

LaFeOs perovskites were also used as nanocatalysts for the heterogeneous Fenton-like reactions of phenol and methyl tert-butyl ether as model contaminants and H2O2 as oxidant [47]. The collected experimental results suggested that the performances of the AFeOs perovskite catalysts are influenced by the intrinsic properties of the perovskite (crystal structure, A site cation, or structural impurities) and processes that occur under the Fenton conditions. 

To determine the stability of the Fe-B nanocomposite as a heterogeneous photo Fenton catalyst, the Fe concentrations in solution after 120 minutes were measured by ICP. The results obtained indicate that the Fe concentration in solution after 20 minutes reaction is less than 1 mg/L, which is negligible. 

Spacek, W., Bauer, R., and Heisler, G. Heterogeneous and homogeneous wastewater treatment - Comparison between photodegradation with TiOz and photo-Fenton reaction, Chemosphere, 30(3) 477-484, 1995. 

In this chapter, the main mechanisms of the homogeneous catalysis of the Fenton s reagent are discussed and special attention is paid in their main drawback as an effective oxidant. Indeed, the catalytic activity ceases after a critical time because iron ions undergoes a chemical speciation during the Fenton process. In order to maintain for a longer time the catalytic activity of the iron ions, a heterogeneous catalyst is proposed. This approach is better because the control over iron ions during the oxidation reaction is improved. 

Costa, RCC Lelis, MFF Oliveira, LCA Fabris, JD Ardisson, JD Rios, RRVA Silva, CN Lago, RM. Novel active heterogeneous Fenton system based on Fe3-xMx04 (Fe, Co, Mn, Ni) The role of species on the reactivity towards H2O2 reactions. Journal of Hazardous Materials, 2006 129, 171-178. 

Fig. 5.8 Examples of oxidative water treatment technologies used in industry, research and development [adapted from FIGAWA (1997), and supplemented by novel methods]. The numbers 1 to 9 refer to the generalized reaction sequences presented in Figure 5-9. a) Oxidation at elevated temperatures between 220°C < T <300°C or supercritical water oxidation at AT >374°C, Ap >221 bar (221000 kPa) (cf Chapter 1) b) oxidation in the presence of bimetallics Fe°/Ni° or Zn°/Ni° (Cheng and Wu, 2001) or heterogeneous oxidation in supercritical water catalyzed by metals Me = Cu, Ag, Au/Ag-alloy c) Fenton reaction at pH <5 d) photo-assisted Fenton reaction, irradiation in the UV-B/VIS range e) the mixture of oxidants O3/H2O2 is called PEROXONE f) ozonation using solid-bed catalysts with conditioned activated carbon (AC) g) vacuum-UV photolysis of water.

Photo-initiated AOPs are subdivided into VUV and UV oxidation that are operated in a homogeneous phase, and in photocatalysis (Fig. 5-15). The latter can be conducted in a homogeneous aqueous phase (photo-enhanced Fenton reaction) or in a heterogeneous aqueous or gaseous phase (titanium dioxide and certain other metal oxide catalysts). These techniques apply UV-A lamps or solar UV/VIS radiation and they are in pre-pilot or pilot status. According to Mukhetjee and Ray (1999) the development of a viable and practical reactor system for water treatment with heterogeneous photocatalysis on industrial scales has not yet been successfully achieved. This is mainly related to difficulties with the efficient distribution of electromagnetic radiation (UV/VIS) to the phase of the nominal catalyst. 

Oxidation of oxalate with OH radicals (formed, e.g. through the Fenton reaction) in addition to the heterogeneous photochemical oxidation may account for the higher rate of oxalate disappearance in an oxygen-saturated suspension, compared to the rate in a deaerated suspension. 

H]-(m/z113) Scheme 3.29 A reaction view for phenol degradation by a heterogeneous Fenton system based on ESI-MS(/MS) data. 

Perovskites with the general elemental composition of ABO3, where B is Fe, also attracted the attention because of their application as catalysts in liquid-phase oxidation reactions. They revealed high catalytic activities in heterogeneous Fenton-like oxidation at neutral conditions [46,47,55,56]. BiFeOs and... 

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