Photocatalytic decolorization of methyl orange solution with potassium peroxydisulfate

Increasing environmental pollution caused by toxic dyes due to their hazardous nature is a matter of great concern. It has been generally agreed that methyl orange (MO) can be effectively degraded in aerated K₂S₂O₈ homogeneous reaction system using near-UV irradiation. In this paper photocatalytic degradation of MO solutions with K₂S₂O₈ was investigated, with particular attention on the possible underlying mechanisms. This report has shown decolorization efficiency of MO increases with the increasing of the dosage of the catalyst. There is no optimal amount of catalyst in our case, where special attention was paid on the nature of the photocatalyst itself. The current research revealed that the decolorization reaction is a pseudo first-order reaction when the concentration of MO is below 20 mg L⁻¹ and the decolorization reaction is zero-order reaction when the concentration of MO is above 100 mg L⁻¹, but the Langmuir-Hinshewood kinetic model does not describe this. The influence of IO₄⁻, BrO₃⁻ and H₂O₂ were investigated in detailed. Several observations indicate that the mechanism is not involved in hydroxyl radical attacks in MO degradation with K₂S₂O₈ by UV irradiation. The possible underlying mechanisms are direct oxidation of the MO by S₂O₈²⁻ and hydrogen attraction by SO₄^•−.      

Oxidation of fast green FCF by the solar photo-Fenton process

This study was conducted to assess the removal efficiency of fast green FCF (a dye) from aqueous medium using the photo-Fenton process. Fenton’s reagent, a mixture of hydrogen peroxide (H₂O₂) and ferric ions (Fe^3t+), used to generate hydroxyl radicals (·OH), was used to attack the target contaminant and degrade it. A visible light source was used to provide the radiation needed in the photo-Fenton method (i.e. H₂O₂/Fe³⁺). The effects of varying the parameters of ferric ion, fast green FCF and hydrogen peroxide concentrations, as well as pH, and light intensity on the reaction rate were determined. More effective and faster than Fenton’s reagent in removing fast green FCF, the results show that the photo-Fenton method completely oxidizes and degrades fast green FCF into CO₂ and H₂O. A tentative mechanism for photobleaching of the dye is proposed.     

Electronic structure of products of interaction between Fe<Subscript>3</Subscript>O<Subscript>4</Subscript> cluster and water and its association with the corrosion behavior of magnetite

Electronic structure of Fe₃O₄ cluster and the products of its interaction with water molecule hydrates H₄O₂ and H₅O₂⁺ and H₃O₂⁻ ions is calculated by the quantum-chemical method DFT B3LYP/6-31G**. The expected behavior of magnetite in the acidic, neutral, and alkaline media is analyzed in the approximation of parameters of their electronic structure (the effective charges, binding and free valences of iron and oxygen atoms). In the interaction between Fe₃O₄ and H₅O₂⁺ (acidic medium), a hydride bond Fe-H forms, and the remainder of magnetite cluster becomes more susceptible to the attack of reagents. By contrast, the interaction of Fe₃O₄ with H₃O₂⁻ (alkaline medium) yields an oxide structure with low chemical activity of both iron and oxygen atoms. The calculated data are in agreement with the experimental data on the corrosion behavior of magnetite.     

UV light-assisted mineralisation and biodetoxification of Ponceau S with hydroxyl and sulfate radicals

The present study reports simultaneous mineralisation and biodetoxification of Ponceau S (3-hydroxy-4-(2-sulfo-4-[4-sulfophenylazo]phenylazo)-2,7-naphthalenedisulfonic acid sodium salt), an azo dye, by UV light assisted oxidation with hydroxyl and sulfate radicals. Metal ion catalysts used in the work were: Fe²⁺ and Ag⁺, and the oxidants used were: hydrogen peroxide and S₂O₈^2?. Strategies adopted to make the processes environmentally benign and economically viable by achieving maximum mineralisation in the shortest possible time are described. Mineralisation efficiency (Em) of various systems was found to follow the order: E_m(Fe²⁺/H₂O₂/UV) > E_m(Fe²⁺/S₂O₈^2?/UV) > E_m(Ag⁺/H₂O₂/UV) ≈ E_m(Ag⁺/S₂O₈^2?/UV). Thus, Fe²⁺ and HP are the most suitable metal ion catalyst and oxidant respectively, showing higher efficiency at pH 3 followed by that at pH 6.6. It is possible to enhance the Fe²⁺/H₂O₂/UV process electrical energy efficiency by maintaining the concentration of Fe at either 0.05 mM or 0.03 mM and that of the oxidant at 2.5 mM. The bioassay study revealed that the Fe²⁺/S₂O₈^2?/UV process biodetoxification efficiency is higher at pH 3 (93.7 %) followed by that at pH 6.6 (80.1 %) at the concentration of Fe ²⁺ and S₂O₈^2? of 0.03 mM and 2.5 mM, respectively. Thus, not only the concentration of Fe²⁺, but also the nature of the oxidant and pH play an important role in the biodetoxification process and S₂O₈^2? possesses higher biodetoxification efficiency than H₂O₂.     

Ferric ion-ascorbic acid complex catalyzed calcium peroxide for organic wastewater treatment: Optimized by response surface method

Hydrogen peroxide (H₂O₂) disproportionation, iron precipitation, and narrow pH range are the drawbacks of traditional Fenton process. To surmount these barriers, we proposed a ferric ion (Fe³⁺)-ascorbic acid (AA) complex catalyzed calcium peroxide (CaO₂) Fenton-like system to remove organic dyes in water. This collaborative Fe³⁺/AA/CaO₂ system presented an obvious improvement in the methyl orange (MO) decolorization, and also effectively eliminated other dyes. Response surface method was employed to optimize the running parameters for this coupling process. Under the optimized arguments (2.76 mmol/L Fe³⁺, 0.68 mmol/L AA, and 4 mmol/L CaO₂), the MO removal achieved 98.90% after 15 min at pH 6.50, which was close to the computed outcome of 99.30%. Furthermore, this Fenton-like system could perform well in a wide range of pH (3–11), and enhance the H₂O₂ decomposition and Fe ions recycle. The scavenger experiment result indicated that hydroxyl radical, superoxide anion free radical, and singlet oxygen were acted on the dye elimination. Moreover, electron spin resonance analysis corroborated that the existences of these active species in the Fe³⁺/AA/CaO₂ system. This study could advance the development of Fenton-like technique in organic effluent disposal.     

Röntgenographische Untersuchungen zum Ablauf einer Redoxreaktion im Bereich ternärer Eisensulfide

X‐ray Diffraction Analysis of a Redox Process Concerning Ternary Iron Sulfides The mixed‐valent ternary iron sulfide Cs₃Fe₂S₄ reacts with water to the structurally related sulfide CsFeS₂. Hydrogen arises during this reaction. Moreover hydroxide and cesium ions were detected in the aqueous phase. Using X‐ray diffraction, the process was followed up by a time lag reaction of Cs₃Fe₂S₄ in an argon atmosphere with defined content of water. Here, cesium hydoxide monohydrate was found as an intermediate product: Cs₃Fe₂S₄ + 2 H₂O → 2 CsFeS₂ + CsH₃O₂ + ¹/₂ H₂.     

Photochemical degradation of typical halogenated herbicide 2,4-D in drinking water with UV/H<Subscript>2</Subscript>O<Subscript>2</Subscript>/micro-aeration

UV/H₂O₂/micro-aeration is a newly developed process based on UV/H₂O₂. Halogenated pesticide 2,4-dichlorophenoxyacetic acid (2,4-D) photochemical degradation in aqueous solution was studied under various solution conditions. The UV intensity, initial 2,4-D concentrations and solution temperature varied from 183.6 to 1048.7 μW·cm⁻², from 59.2 to 300.0 μg·L⁻¹ and from 15 to 30°C, respectively. The concentration of hydrogen peroxide (H₂O₂) and pH ranged from 0 to 50 mg·L⁻¹ and 5 to 9, and different water quality solutions (tap water, distilled water and deionized water) were examined in this study. With initial concentration of about 100 μg·L⁻¹, more than 95.6% of 2,4-D can be removed in 90 min at intensity of UV radiation of 843.9 μW·cm⁻², H₂O₂ dosage of 20 mg·L⁻¹, pH 7 and room temperature. The removal efficiency of 2,4-D by UV/H₂O₂/micro-aeration process is better than UV/H₂O₂ process. The photodecomposition of 2,4-D in aqueous solution follows pseudo-first-order kinetics. 2,4-D is greatly affected by UV irradation intensity, H₂O₂ dosage, initial 2,4-D concentration and water quality solutions, but it appears to be slightly influenced by pH and temperature. There is a linear relationship between rate constant k and UV intensity and initial H₂O₂ concentration, which indicates that higher removal capacity can be achieved by the improvement of these factors. Finally, a preliminary cost analysis reveals that UV/H₂O₂/micro-aeration process is more cost-effective than the UV/H₂O₂ process in the removal of 2,4-D from drinking water.     

Kinetics and mechanism of the formation of (1,8)bis(2-hydroxybenzamido)3,6-diazaoctaneiron(III) and its reactions with thiocyanate, azide, acetate, sulfur(IV) and ascorbic acid in solution, and the synthesis and characterization of a novel oxo bridged diiron(III) complex. The role of phenol–amide–amine coordination

The interaction of (1,8)bis(2-hydroxybenzamido)3,6-diazaoctane (LH₂) with iron(III) in acidic medium resulted in the formation of a mononuclear complex, Fe(LH₃)⁴⁺ which further yielded, [Fe(LH₂)]³⁺, [Fe(LH)]²⁺, and [FeL]⁺ due to protolytic equilibria. The formation of [Fe(LH₃)]⁴⁺ was investigated under varying [H⁺]_T (0.01–0.10 mol dm⁻³) and [Fe³⁺]_T (1.00 × 10⁻³–1.70 × 10⁻², [L]_T = 1.0 × 10⁻⁴ mol dm⁻³) (I = 0.3 mol dm⁻³, 10% MeOH + H₂O, 25.0 °C). The reaction was reversible and displayed monophasic kinetics; the dominant path involved Fe(OH)(OH₂) ₅ ²⁺ and LH ₄ ²⁺ . The mechanism is essentially a dissociative interchange (I _d) and the dissociation of the aqua ligand from the encounter complex, [Fe(OH₂)₅OH²⁺, H₄L²⁺] is rate limiting. The ligand binds iron(III) in a bidentate ([Fe(H₃L)]⁴⁺), tetradentate ([Fe(H₂L)]³⁺), pentadentate ([Fe(HL)]²⁺) and hexadentate fashion ([FeL]⁺) under varying pH conditions. Iron(III) promoted deprotonation of the amide and phenol moieties and chelation driven deprotonation of the sec-NH ₂ ⁺ of the trien spacer unit are in tune with the above proposition. The mixed ligand complexes, [Fe^III(LH)(X)] (X = N ₃ ⁻ , NCS⁻, ACO⁻) are also reversibly formed in solution thus indicating that there is a replaceable aqua ligand in the complex conforming to its octahedral coordination, [Fe(LH)(OH₂)]²⁺, the bound ligand is protonated at the sec-NH site. Despite the multidentate nature of the ligand the Fe^III complexes are prone to reduction by sulfur(IV) and ascorbic acid. The redox reactions of different iron(III) species, Fe^III(LH_i) which involved ternary complex formation with the reductants have been investigated kinetically as a function of pH, [S^IV]_T and [ascorbic acid]_T. The substantial pK perturbation of the bound ascorbate in [Fe(LH)(HAsc/Asc)]^+/0 (ΔpK _{{[Fe(LH)(HAsc)] − HAsc − }} > 6) is considered to be compelling evidence for chelation of HAsc⁻/Asc²⁻ leading to hepta coordination of iron(III) in the ascorbate complexes. A novel binuclear complex with composition, [Fe^III ₂C₂₀N₄H₃₅O₁₁ (NO₃)] has been synthesized and characterized by i.r., u.v.–vis, e.s.r., e.s.i.-Mass, ⁵⁷Fe Mossbauer spectroscopy and magnetic moment measurements. The complex was isolated as a mixture of two forms C ₁ and C ₂ with 75.3 and 24.7%, respectively as computed from Mossbauer data. The isomer shift (δ) (quadrupole splitting, ΔE _Q) are 0.32 mm s⁻¹ (0.75 mm s⁻¹) and 0.19 mm s⁻¹ (0.68 mm s⁻¹) for C ₁ and C ₂, respectively. The variable temperature magnetic moment measurements (10–300 K) of the sample showed that C ₁ is an oxo dimer exhibiting antiferromagnetic interaction between the iron(III) atoms (S ₁ = S ₂ = 5/2, J = − 120 cm⁻¹) while the dimer C ₂ is a high spin species (S ₁ = S ₂ = 5/2) and exhibits normal paramagnetism obeying the Curie law. The cyclic voltametry response of the sample (DMF, [TEAP] = 0.1 mol dm⁻³) displayed quasi-reversible responses at − 0.577 V and − 1.451 V (versus SCE). This is in tune with the fact that the C ₂ species reverts rapidly in solution to the relatively more stable oxo-bridged dimer (C ₁) which is reduced in two sequential steps: C₁ + e⁻ → [FeL]⁺ + Fe^II; [FeL]⁺ + e⁻ → Fe^IIL, the high labilility of the Fe^II complex is attributed to the irreversibility. The X-band e.s.r. spectrum of the polycrystalline sample at room temperature displayed a weak (unresolved) band at g = 4.2 and a strong band at g = 2.0 with hyperfine splitting due to the coordinated nitrogen (I = 1). At 77 K the band at g = 4.2 is intensified while that at g = 2 is broadened to the extent of near disappearance in agreement with the presence of the exchange coupled iron(III) centres. Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users. An erratum to this article is available at .     

Distribution and reaction dynamics of iron(III) hydrolytic cationic species

Studying hydrolysis of iron(III) ions contained in the concentration 0.01 mol/L in the Fe³⁺-NO₃⁻H₂O system as a function of increasing pH, we determined the regions of the dominance of various complex species and their interconversions. The reaction dynamics of transformations of various hydroxo complex species is represented.     

Photooxidation of carbonyl sulfide in the presence of the typical oxides in atmospheric aerosol

Carbonyl sulfide (COS) is one of the most abun-dant sulfur containing gases in the troposphere andlower stratosphere[1,2]. It is relatively inert in the tro-posphere and can be transported into the stratosphere,where it dissociates under the solar ultravi…     

Synthesis, structure, and properties of a binuclear Fe(III) complex with N-(1-propanol)-N,N-bis(3-tert-butyl-5-methyl-2-hydroxybenxyl)amine

Mannich reaction of 2-Amino propanol, 2-tert-butyl-4-methylphenol, and formaldehyde in the ratio of 1:2:2 provides a new compound, N-(1-propanol)-N,N-bis(3-tert-butyl-5-methyl-2-hydroxybenxyl)amine (H₃L), which has been characterized by X-ray crystallography and elemental analysis. In the presence of Et₃N, the reaction of H₃L and FeCl₃·6H₂O gives a dinuclear Fe(III) complex [Fe₂L₂] 1, which has been characterized by X-ray crystallography, magnetic measurement, and cyclic voltammetry. The value of μ_eff at room temperature (5.97 μ_B) is much less than the expected spin-only value (8.37 μ_B) of two high spin (hs) Fe³⁺ (S = 5/2) ions [μ = g[∑ZS(S + 1)]^1/2], indicating there are strong coupling interactions between Fe³⁺ ions. The magnetic behavior of 1 denotes the occurrence of intramolecular antiferromagnetic interactions (J = −13.35 cm⁻¹ ). CV of 1 reveals two reversible waves at 0.433 and 1.227 V versus AgCl/Ag, which can be ascribed to the successive redox coupling of Fe^IIFe^II/Fe^IIIFe^II and Fe^IIIFe^II/Fe^IIIFe^III, respectively.     

Catalytic and inhibition functions of iron ions in the chain oxidation of acrylic acid

The kinetics of acrylic acid oxidation in the presence of iron ions $ (T = 333K,_{P_{O_2 } } = 1 atm) $ (T = 333K,_{P_{O_2 } } = 1 atm) has been investigated by measuring the oxygen uptake. The reaction has an induction period τ, after which the O₂ uptake is described by the parabolic kinetic law δ[O₂]^0.5 = b(t − τ). The parameter b characterizing the catalytic oxidation of acrylic acid has been calculated. Upon the introduction of an initiator (azobisisobutyronitrile), the oxidation has no induction period, but the autoacceleration of the reaction is still observed. A mechanism is suggested for the process. This mechanism includes initiation due to the interaction of the resulting peroxide and hydroperoxide groups with Fe²⁺ and Fe³⁺ ions and chain termination via the reaction R^· + Fe³⁺, where R^· is an acrylic acid macroradical.     

Nature of the silver precipitation obtained by cementation from thiosulphate solutions

The morphology and composition of the deposits formed on the surface of magnesium disk during cementation from thiosulphate solutions (0.0025–0.1M) [Ag(S₂O₃)₂]³⁻ + 0.5M S₂O₃ ²⁻ have been studied. A porous deposit with low adhesion is formed on the surface of the magnesium metal substrate. Within a wide range of [Ag(S₂O₃)₂]³⁻ ion concentrations, sulfur as well as silver are constituents of the deposit at the initial stages of cementation and at the end of the reaction. This is attributed to the electrochemical behaviour of magnesium in thiosulphate solutions resulting in the exceeding of current limit on cathode for pure silver reduction. Hence, parallel electrochemical reactions take place that are very close in their values to the standard redox potentials of reduction of [Ag(S₂O₃)₂]³⁻ ions to Ag⁰ and S₂O₃2− ions to S²⁻. Sulfur content in the cement deposits increases with the decrease in [Ag(S₂O₃)₂]³⁻ ion concentration and increase in cementation time. This tendency is also observed with the decreasing solution temperature.     

Photochemical synthesis of cadmium sulfide nanoparticles

The formation of cadmium sulfide nanoparticles upon UV irradiation of aqueous solutions of cadmium thiosulfates was established on the basis of spectroscopic and macroscopic data. The yield and size of the cadmium sulfide nanoparticles depend on the ratio of cadmium to thiosulfate ions in solution, the concentration of the solution, and the irradiation duration. The cadmium sulfide nanoparticles with a diameter of 4 nm were obtained by the photolysis of solutions with a concentration of 10⁻³ mol L⁻¹ at the ratio S₂O₃ ²⁻: Cd²⁺ = 2: 1.     

Engineering FeS2 nanoparticles on tubular g-C3N4 for photo-Fenton treatment of paint wastewater

An efficient photo-Fenton catalyst （Fe S₂@HTCN） was designed by maximizing the synergistic effect of Fe S₂nanoparticles and hollow tubular g-C₃N₄（HTCN）.Molecule self-assembly and molten salts-assisted calcination were used to engineering the hollow structured g-C₃N₄before anchoring Fe S₂nanoparticles on the walls of HTCN via reflux method.Compared to bulk g-C₃N₄,the unique structure of HTCN and het...     

BiOBr/g-C3N4 S型异质结无H2O2光-自芬顿高效催化降解RhB

通过焙烧-超声混合法成功地制备了BiOBr/g-C₃N₄ S型异质结复合光催化剂。采用多种表征手段对样品物理属性进行了表征,包括X射线多晶粉末衍射仪(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、紫外可见漫反射光谱(UV-VisDRS)。研究了所制备样品有/无Fe³⁺的光-自芬顿催化/光催化降解罗丹明B (RhB)性能。通过捕获实验确定了光催化反应中的主要活性物种,提出了光-自芬顿反应的降解机理。研究结果表明,BiOBr/g-C₃N₄ S型异质结能原位生成H₂O₂,添加Fe³⁺后,H₂O₂被原位活化成活性物种且光生电流和载流子分离效率获得显著提高。该光-自芬顿过程能高效降解RhB,其反应速率常数为0.208 min^-1,约为无Fe³⁺光催化反应速率常数的5.3倍,在光-自芬顿循环使用过程中表现出良好的稳定性。Fe³⁺的加入促进了光生电荷的分离和H₂O₂的活化,超氧阴离子自由基(·O₂^-)、空穴和羟基是光-自芬顿催化过程中的主要活性物种,且·O₂^-作用更大。     

Conversion of Chromium(III) Propionate to Chromate/dichromate(VI) by the Advanced Oxidation Process. Pretreatment of a Biomimetic Complex for Metal Analysis

The use of H₂O₂ and UV irradiation to remove organic ligands in a chromium(III) complex for the subsequent chromium analysis is reported. The Advanced Oxidation Process (AOP) using a 5.5-W UV lamp, H₂O₂ and Fe²⁺/Fe³⁺ as catalyst (photo Fenton process) was found to give complete and quantitative Cr(III) → Cr(VI) conversion and removal of ligands in chromium(III) propionate [Cr₃O(O₂CCH₂CH₃)₆(H₂O)₃]NO₃, a biomimetic chromium species, as subsequent chromium analyses by the 1,5-diphenylcarbazide method and atomic absorption revealed. The current process eliminates the need for mineralization and/or dissolution of the matrix in order to remove the organic ligand, the traditional pretreatments of a sample for metal analysis. Studies to optimize the conditions for the oxidation processes, including the use of Fe²⁺/Fe³⁺ catalyst, length of UV irradiation, H₂O₂ concentration, pH, power of UV lamp, and reactor size, are reported.     

Effect of various oxidants in a photocatalysis/filtration system for the treatment of contaminants

This study was conducted to investigate the effect of a photocatalysis/oxidant system for the treatment of humic acid and hazardous heavy metals in aqueous solutions. Hydrogen peroxide, ozone, and potassium peroxodisulfate were tested as oxidants. The effect of oxidant concentration was conducted with a pH of 7, a UV intensity of 64 W, and a TiO₂ dosage of 0.3 g L⁻¹. The oxidant addition in the UV/TiO₂ system enhanced the degradation efficiency of humic acid and hazardous heavy metals compared to no addition of an oxidant. The addition of oxidants over the amounts of H₂O₂ 50 mg L⁻¹, O₃ 20 g m⁻³, and K₂S₂O₈ 50 mg L⁻¹ inhibits the system efficiency. The negative effect of higher oxidant concentrations likely results from OH radical quenching caused by the excess oxidant. Therefore, the optimal dosages of oxidants such as a hydrogen peroxide, ozone, and potassium peroxodisulfate were found to be 50 mg L⁻¹, 20 g m⁻³, and 50 mg L⁻¹, respectively. The degradation efficiency of UV/TiO₂/oxidant systems for the removal of humic acid and hazardous heavy metals was much greater in the UV/TiO₂/H₂O₂ system using H₂O₂ as an oxidant.     

Spectral characteristics of water clusters upon interaction with oxygen molecules and chlorine ions

The interactions of a 6O₂ + (H₂O)₅₀ system with two, four, or six Cl⁻ ions are studied by the molecular dynamics method. The integral intensity of IR and Raman spectra decreases with an increase in the number of Cl⁻ ions surrounding the system. The values of real and imaginary parts of dielectric permittivity increase with the rise in the frequency reaching maxima in the 850 ≤ ω ≤ 950 cm⁻¹. As a result of interactions between ions and the formed (O₂)₆ (H₂O)₅₀ cluster, the pattern of the reflection spectrum of IR radiation becomes smoother. The interaction between 6O₂ + (H₂O)₅₀ system and Cl⁻ ions leads to the substantial increase in the power of emitted radiation. With time, Cl⁻ ions gradually leave the interaction zone with the system. Maximum residence time of the last ion near the system boundary does not exceed 3 ps. Cl⁻ ions located closer to O₂ molecules do not penetrate into the depth of an (O₂)₆ (H₂O)₅₀ cluster.     

Photo-Fenton degradation of resorcinol mediated by catalysts based on iron species supported on polymers

Novel Fe supported catalysts were prepared by immobilizing iron species on commercial polyethylene via three different methods: (1) acidic pre-treatment of the polyethylene followed by impregnation in aqueous Fe(NO₃)₃, (2) TiO₂ photo-catalytic pre-treatment of the polyethylene followed by forced hydrolysis of Fe(NO₃)₃, and (3) direct photo-Fenton attack with concomitant iron deposition on the polyethylene surface. The last method required soft conditions and led to the most photo-active Fe–polyethylene film. With this material, at a non-adjusted initial pH of 5.6 in the presence of H₂O₂, total degradation and 50% of resorcinol mineralization were observed in 40 and 60 min, respectively. Photo-Fenton functionalization/Fe-deposition process was also applied to polypropylene, high-impact polystyrene, and polymethylmethacrylate films. The efficiencies of all the prepared heterogeneous photo-catalysts were similar to that of an homogeneous photo-Fenton system containing the same amount of Fe^3+/2+ that leached during “heterogeneous” processes. That demonstrated than in our systems mainly homogeneous photo-Fenton reactions were responsible for the resorcinol degradation. The photo-catalytic activity observed for the Fe/polymer was a function of the specific polymer capacity to release the initially deposited iron into the solution.