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Ordered nanocrystalline titania-mesoporous silica nanotube structures are synthesized by hydrolysis of the titania precursor inside pours silica shell. Silica coating surrounding carbon nanotubes was further removed by thermal reduction. The proposed method of functionalization silica channels with the titania nanoparticles preclude aggregation of TiO2 nanoparticles. The nanocrystalline silica/titania (mt-SiO2/TiO2) nanotubes were prepared according to the describe method has high specific surface area and possesses excellent photocatalytic properties capable of decomposing phenol and methylene blue in a short time. Since the nanocrystalline TiO2 is produced in the wall of the mesoporous silica tube, phenol or dye molecules can react with TiO2 nanoparticles from both the inside and outside.

Titanium dioxide thin films doped with the same amount of neodymium were prepared using two different magnetron sputtering methods. Thin films of anatase structure were deposited with the aid of Low Pressure Hot Target Magnetron Sputtering, while rutile coatings were manufactured using High Energy Reactive Magnetron Sputtering process. The thin films composition was determined by energy dispersive spectroscopy and the amount of the dopant was equal to 1 at. %. Structural properties were evaluated using transmission electron microscopy and revealed that anatase films had fibrous structure, while rutile had densely packed columnar structure. Atomic force microscopy investigations showed that the surface of both films was homogenous and consisted of nanocrystalline grains. Photocatalytic activity was assessed based on the phenol decomposition. Results showed that both thin films were photocatalytically active, however coating with anatase phase decomposed higher amount of phenol. The transparency of both thin films was high and equal to ca. 80% in the visible wavelength range. The photoluminescence intensity was much higher in case of the coating with rutile structure.

The present work focused on application of ZnO-NPs@bentonite, as a catalyst, for disposal of different pollutants such as dyes, phenol compounds and Cr(VI) ions from water. The prepared ZnO–bentonite nanocomposite was characterized by using FT-IR, X-ray powder diffraction, and Scanning electron microscopy analysis. The results showed that the amount of zinc oxide influenced the catalytic performance of ZnO–bentonite nanocomposite. Small amounts of zinc oxide on bentonite have a positive effect whereas increase in weight ratios has a negative effect. [ABSTRACT FROM AUTHOR]

Composite photocatalysts containing TiO 2 nanoparticles grown on nanosheet-structured graphitic carbon nitride (g-C 3 N 4 ) were synthesized using a facile calcination approach. A series of g-C 3 N 4 /TiO 2 nanocomposites was prepared by varying the amount of the urea precursor from 1 g to 5 g. The as-prepared catalysts were characterized by X-ray diffraction; scanning electron microscopy; N 2 adsorption-desorption isotherm analysis; and Fourier transform infrared, X-ray photoelectron, and UV–Vis spectroscopies. The results revealed that small TiO 2 particles were well dispersed on the surface of the g-C 3 N 4 nanosheets. Compared with pure TiO 2 nanoparticles, the obtained g-C 3 N 4 /TiO 2 nanocomposites showed enhanced photocatalytic activity toward the degradation of phenol as a result of improved separation of photogenerated electrons and holes derived from the synergistic interaction of TiO 2 and g-C 3 N 4 . The g-C 3 N 4 /TiO 2 composite prepared with 4 g of urea precursor showed the best photocatalytic performance toward phenol decomposition with a degradation rate of 99.4%. It was found that during the degradation process, p -benzoquinone, catechol, and hydroquinone were generated; hydroquinone was identified as the main intermediate product. Furthermore, mechanisms were proposed to explain the electron-hole separation and transport over the g-C 3 N 4 /TiO 2 photocatalyst as well as phenol degradation under ultraviolet light irradiation. [ABSTRACT FROM AUTHOR]

In this work, the synergetic effect of TiO 2 and Fe 3+ in pulsed discharge plasma has systematically investigated using phenol as the probe molecule. The dominant effects of TiO 2 and Fe 3+ dosage were firstly studied, and then phenol degradation was investigated in four parallel experiments including plasma alone, plasma/Fe 3+ , plasma/TiO 2 and plasma/Fe 3+ /TiO 2 . The experimental results showed that the phenol removal efficiency in plasma/Fe 3+ /TiO 2 system increased by 25% in comparison with plasma alone, which were only 9% and 10% in plasma/TiO 2 and plasma/Fe 3+ system, indicating a significantly synergistic effect between Fe 3+ and TiO 2 . To illustrate the synergetic effect of TiO 2 and Fe 3+ ions, the TiO 2 structural characterization was analyzed by XPS, UV–vis spectra and XRD, and Fe 2+ and OH concentration was also determined during discharge process. The Fe 3+ ions and excited nitrogen from plasma discharge were doped on TiO 2 particles, which narrowed the band gap of TiO 2 from 3.0 eV to 2.0 eV and enlarged the absorption edge at around 600 nm, and therefore enhanced the photocatalytic activity in the visible light. The co-doping of Fe 3+ and nitrogen significantly increased the separation rate of photo-generated electrons and holes and prolonged their lifetime. The photoelectron-transfer pathway was blocked by Fe 3+ , the Fe 3+ ions could be changed to Fe 2+ ions using photoelectron on TiO 2 surface, inducing Fenton-like reaction for the enhancement of the OH formation rate in the plasma/TiO 2 /Fe 3+ system. The concentration of OH increased from 14.8 × 10 −5 mol L −1 in the plasma/TiO 2 system to 20.6 × 10 −5 mol L −1 in the plasma/TiO 2 /Fe 3+ system. [ABSTRACT FROM AUTHOR]

In this present work, high specific surface area and strong visible light absorption nitrogen doped TiO2-SiO2 photocatalyst was synthesized by using sol-gel coupled with hydrothermal treatment method. Nitrogen was found to improve the specific surface area while it also distorted the crystal phase of the resulting N-TiO2-SiO2 catalyst. As the N/ (TiO2-SiO2) molar ratio was more than 10%, the derived catalyst presented the superior specific surface area up to 260 m2/g. Nevertheless, its photoactivity towards phenol removal was observed to significantly decrease, which could results from the too low crystallinity. The nitrogen content in N-TiO2-SiO2 catalyst was therefore necessary to be optimized in terms of phenol removal efficiency and found at ca. 5%. Under UVA light and natural sunlight irradiation of 80 min, N(5%)-TiO2-SiO2 catalyst presented the phenol decomposition efficiencies of 68 and 100%, respectively. It was also interestingly found in this study that the reaction rate was successfully expressed using a Langmuir-Hinshelwood (L-H) model, indicating the L-H nature of photocatalytic phenol decomposition reaction on the N-TiO2-SiO2 catalyst.

Highlights: [•] Carbon nanotubes can generate SO4 −• from peroxymonosulfate and peroxydisulfate. [•] Nitrogen doping increases the catalytic performance in activating peroxymonosulfate. [•] Pristine and N-modified carbon nanotubes are green catalysts for organic decomposition. [Copyright &y& Elsevier]

Ultrasound energy has been successfully employed to synthesize CdSe/TiO nanocatalysts for the photocatalytic degradation of phenol under solar light irradiation. The photocatalytic performance test was carried out using TiO as well as synthesized CdSe/TiO nanocatalysts. Nanocatalyst characterization was accomplished using XRD, SEM, FTIR, BET and UV-vis spectroscopy. It was shown that the synthesized nanocatalysts have crystal characteristics and are in nano-scale size range. The coupled nanocatalyst has shown a shift in the absorption spectrum from the UV range to the visible range. The results of photocatalytic tests showed that the CdSe/TiO coupled nanocatalyst could remove phenol from wastewater under solar light irradiation, while TiO did not have enough activity in this process. It is also shown that the CdSe nanoparticles act as photosensitizers, not only extending the spectral response of TiO to the visible region but also reducing the electron-hole recombination. Furthermore, the CdSe/TiO synthesized samples provided more photomineralization efficiency than that of TiO in terms of total organic carbon analysis. [ABSTRACT FROM AUTHOR]

Abstract: The decomposition mechanism of high concentration of phenol solution in water plasmas at atmospheric pressure was investigated at different arc currents. The results showed that the removal efficiencies of phenol, total organic carbon, and chemical oxygen demand were increased with the increase in arc current. The concentration of phenol was reduced from 52.8gL−1 down to 1.0×10−5 gL−1 at an arc current of 8A with the energy yield of 8.12gkWh−1. Major gaseous compounds were H2, CO2, CO, and CH4. However, at a low arc current, trace levels of benzene (C6H6), and cyclopentadiene (C5H6) were detected in effluent gas, and formic acid (HCOOH) and formaldehyde (HCHO) were observed in liquid effluent. By the analysis of reaction intermediates and a calculation of carbon balance, the main reaction pathways were proposed as follows: firstly, electron dissociation in arc region to generate phenoxy (C6H5O) radical; second, chemical oxidation or reduction in plasma flame region to form C6H5O and C6H6. After phenol decomposition, the generated intermediate species would undergo complex reactions to form stable compounds in plasma flame region. The most favorable mechanism is the formation of CO, which is conducted by the ring open step of C6H5O and C6H6 by thermal decomposition or the attachment of active radicals such as O, H, and OH with respect to CO generation. In downstream region, the generated intermediate species were easily recombined with H or oxidized by OH to form unwanted products, such as HCOOH, HCHO, and H2O2. [Copyright &y& Elsevier]

Abstract: Bare TiO2 photocatalysts made up of polyhedral nanoparticles have been prepared by flame hydrolysis. In order to obtain deeper understanding of the interplay between the properties determining the photocatalytic performance, surface, aggregation and photocatalytic properties have been analyzed and compared. The aggregation of nanoparticles in aqueous solution of NaCl was determined by dynamic light scattering (DLS) technique. The average hydrodynamic diameters of the aggregates investigated under environmentally relevant conditions do not differ significantly in the pH range of 5–6. Zeta potential measurements were also done during DLS analysis, which revealed remarkably low pHIEP values for our flame made samples comparing to the commercial titanias. Furthermore an explicit correlation between the isoelectric points and the synthesis parameters was revealed. O 1s XP spectra for the high activity samples were also recorded and interpreted. Oxygen consumption experiments were used to test the photocatalytic activity in suspensions. The method was found to be not only rapid and inexpensive but also reasonably reproducible. Normalizing the oxygen consumption rate with the specific surface area of the sample and the concentration of the suspension, a good correlation could have been found with the traditionally determined photocatalytic activity. HPLC measurements were used to study the degradation mechanism of phenol via determining the concentration profile of various dihydroxy intermediates, i.e., hydroquinone (HQ) and pyrocatechol (PC). The quality of the photocatalyst strongly affects the maximum ratio of HQ:PC during the photocatalytic degradation process. For our catalysts higher pyrocatechol concentrations were measured than for Degussa P25. TOC measurements were used to follow the complete mineralization. Using our best photocatalysts (e.g., anatase:rutil ratio of 82:18 and mostly polyhedral particles, with 21m2/g BET surface area), phenol concentration decreased faster than for P25, however, the mineralization rate was somewhat lower. This can be attributed to the lower adsorption capacity of our polyhedral particles against PC and carboxylate containing intermediates formed during the more advanced stages of decomposition. These data elucidate, that hydrophilicity, O2-consumption properties and adsorption/complexation of the target compounds and their degradation products are equally important parameters in determining the photocatalytic performance of catalysts, which otherwise possess similar material properties. [Copyright &y& Elsevier]

Abstract: Nanosized TiO2 photocatalysts were synthesized via hydrogen–air flame hydrolysis by using two slightly different, home made diffusion flame burners (Burners A and B). Titanium(IV) chloride vapor was introduced into the flame via bubbling dry air throughout the precursor liquid. X-ray diffraction (XRD) measurements revealed that the particles are anatase–rutile mixtures with a phase composition ranging from 98:2 to 57:43 anatase to rutile weight ratio. The hydrogen–oxygen molar ratio in the flame, as well as the precursor vapor feeding rate were found to be the key parameters which determine both particle structure and morphology. Spherical and polyhedral particles with significantly varying photocatalytic activity were produced in Burner A by increasing the precursor vapor feeding rate at a constant hydrogen–oxygen molar ratio, the photocatalytic activity increased for samples synthesized. The differences in particle size, specific surface area and anatase–rutile composition were found to be marginal but the particle shape changed from spherical to polyhedral by increasing that parameter. From this, it was concluded that particle shape plays an important role in photocatalytic activity, the faceted particles are better photocatalysts than spherical ones. With Burner B, predominantly polyhedral particles were obtained, some of them with further improved photocatalytic activity. Synthesis parameters for obtaining maximum activity have been established for both burners. Our results prove, that bare (undoped) TiO2 photocatalysts with photocatalytic activity significantly better than that of P25 can routinely be prepared and their performance optimized via the fine-tuning of the synthesis parameters employed. [Copyright &y& Elsevier]

Dielectric barrier discharge (DBD) plasma technology combined with Ag/TiO 2 composites for phenol degradation was investigated. The TEM, XRD, XPS results showed that Ag was successfully doped on TiO 2. PL results indicated that the doped Ag on TiO 2 obviously decreased the recombination rate of electron-hole pairs. The effect of silver loading, Ag/TiO 2 introduction dosages, initial phenol concentration, applied voltage on Ag/TiO 2 catalytic performance were also studied and analyzed. With introduction of 0.2 g L−1 0.5 wt% Ag/TiO 2 , the phenol removal efficiency was enhanced by 6% at 17 kV and 20 kV, the addition of Ag/TiO 2 has slightly inhibiting effect on phenol degradation at 22 kV. The NO 2 − and NO 3 − concentrations were also measured by IC. The results showed that NO 3 −-N concentration reached 37 mg L−1 at 22 kV, and NO 3 −-N obviously decreased from 37 mg L−1 to 25 mg L−1 and NO 2 −-N increased from 0.10 mg L−1 to 0.24 mg L−1 with adding Ag/TiO 2. The reason of inhibiting effect of Ag/TiO 2 at 22 kV could be that the NO 3 − from discharge was involved in Ag/TiO 2 catalytic reaction, and the reduction of NO 3 − could inhibit the electrons transfer from the Ag metal to O 2 , resulting in the lower phenol removal efficiency. • The process of introducing Ag/TiO 2 to promote the degradation of phenol was explored in dielectric barrier discharge (DBD) plasma system. • The influence of nitrate produced from discharge on catalytic reaction in the presence of Ag/TiO 2 was studied. • The interactions between reactive oxygen species (ROS), nitrate and Ag/TiO 2 were deduced. [ABSTRACT FROM AUTHOR]

New WO x–TiO2 photocatalysts were prepared via sol–gel method from tetraisopropyl orthotitanate and WO2. For comparison TiO2 was also prepared by the same method. These photocatalysts were tested for phenol degradation in an aqueous solution under UV irradiation. Experimentally measured OH radicals formation on WO x–TiO2 photocatalysts was quantitatively much higher than on TiO2, what increased their photocatalytic activity towards phenol decomposition. Band gap of the prepared photocatalysts was calculated from the obtained derivatives of UV–Vis/DR spectra and it was observed that Eg decreased with increasing calcination temperature in both, TiO2 and WO x–TiO2. This was caused by the improving crystallinity of anatase phase and formation of rutile, which had a lower value of Eg than anatase. In general the presence of WO x in TiO2 suppressed transformation of anatase to rutile. [ABSTRACT FROM AUTHOR]

Abstract: Nanosized TiO2 photocatalysts were synthesized via hydrogen–air flame hydrolysis. X-ray diffraction (XRD) measurements revealed that the TiO2 samples thus prepared consisted mainly of anatase (79–98wt%) and the rest is rutile. Average particle diameters from TEM measurements were found to vary between 48 and 63nm. The specific surface area of the samples was found to be practically independent of the synthesis parameters employed (20–32m2 g−1). Photocatalytic activity of the catalysts was studied by using various model compounds. In spite of their very similar properties, the initial decomposition rate of phenol and methanol showed up to threefold variations within the series of the samples, and it was significantly higher for the best catalyst than that determined for Degussa P25. Our TEM measurements demonstrated that in the less active catalysts the dominant morphology of the particles is spherical, while polyhedral (cubic or hexagonal) shapes predominate in the samples with superior photocatalytic activity. From these observations, we concluded, that the shape of the primary particles (both in the case of our home made ones and in various batches of Degussa P25) strongly influence the photocatalytic activity of titania nanoparticles. [Copyright &y& Elsevier]

Decomposition of environmental contaminants such as phenol contained in water was investigated using a pulsed high-voltage gas-phase discharge on the water surface (water surface plasma). The discharge consists of streamer channels that spread out over the water surface. Discharge characteristics were dependent upon the distance between the needle-tip electrode and the water surface, the shape of the submerged ground electrode, and the composition of the gas enveloping the electrode. When the electrode-water distance was decreased, the discharge mode changed from corona to streamer, and then, finally, to a water surface discharge when the distance was small. Argon gas was the most effective enveloping gas for decomposing phenol in water (compared to oxygen or air). When the gas flow rate was increased to carry away the active species formed in the gas phase; the decomposition rate did not change in argon, but decreased in oxygen. The shape of the submerged ground electrode influenced the discharge state and the phenol decomposition rate. A ring-shaped ground electrode was more effective for decomposition of phenol than straight or semicircular shapes. Experiments were performed to identify the mechanism(s) responsible for the decomposition of organic materials in water. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 and Fe–C–TiO2 photocatalysts have been immobilized on the cotton material and used in a flow photocatalytic reactor for phenol decomposition. The cotton material has been applied as a support for photocatalyst, because can be easily removed and replaced in a reactor, what facilitates the performance of the photocatalytic process. Fe–C–TiO2 photocatalyst has been prepared by modification of TiO2 fine particles of anatase structure with FeC2O4 through heating in Ar at 500°C. The immobilized photocatalysts could efficiently decompose phenol in multiple use, Fe–C–TiO2 showed higher photocatalytic activity than TiO2, around 15–18mg and 15–16mg of phenol have been decomposed after 5h of UV irradiation on Fe–C–TiO2 and TiO2, respectively. After addition of H2O2 the phenol decomposition and the mineralization degree have been accelerated, especially with immobilized Fe–C–TiO2 photocatalyst, in case of that the photo-Fenton reaction occurred. In the presence of H2O2 around 26–28mg and 21–24mg of phenol have been decomposed on Fe–C–TiO2 and TiO2 respectively, after 5h of UV irradiation. [Copyright &y& Elsevier]

Abstract: Fe–C–TiO2 photocatalysts which contained the residue carbon (0.2–3.3mass%) were prepared from a mixture of TiO2 and FeC2O4 through the heating at 673–1173K in Ar. These photocatalysts did not show a high adsorption of phenol, but they were active in photo-Fenton reactions during decomposition of phenol under UV irradiation with addition of H2O2. It was proved that Fe2+ governed the photoactivity of Fe–C–TiO2 photocatalysts, it decreased with heat-treatment temperature above 773K. For comparison, Fe–TiO2 photocatalyst was prepared by heating TiO2 and FeC2O4 at 823K in air for 3h. Phenol decomposition was going much slower on Fe–TiO2 photocatalyst in comparison with Fe–C–TiO2, of which mechanism was different, on the former phenol was decomposed by the radical reaction, on the latter through a complex reaction with iron and intermediates of phenol decomposition. Therefore carbon-coating TiO2 was found to be advantageous for mounting iron and its application for the phenol decomposition via photo-Fenton process. [Copyright &y& Elsevier]

Abstract: H2O2 used in the photo-Fenton reaction with iron catalyst can accelerate the oxidation of Fe2+ to Fe3+ under UV irradiation and in the dark (in the so called dark Fenton process). It was proved that conversion of phenol under UV irradiation in the presence of H2O2 predominantly produces highly hydrophilic products and catechol, which can accelerate the rate of phenol decomposition. However, while H2O2 under UV irradiation could decompose phenol to highly hydrophilic products and dihydroxybenzenes in a very short time, complete mineralisation proceeded rather slowly. When H2O2 is used for phenol decomposition in the presence of TiO2 and Fe-TiO2, decrease of OH formed on the surface of TiO2 and Fe-TiO2 has been observed and photodecomposition of phenol is slowed down. In case of phenol decomposition under UV irradiation on Fe-C-TiO2 photocatalyst in the presence of H2O2, marked acceleration of the decomposition rate is observed due to the photo-Fenton reactions: Fe2+ is likely oxidized to Fe3+, which is then efficiently recycled to Fe2+ by the intermediate products formed during phenol decomposition, such as hydroquinone (HQ) and catechol. [Copyright &y& Elsevier]

Abstract: The preparation of mesoporous titanium dioxide by using the sol–gel method is described. For the syntheses a triblock copolymer (P-123) surfactant as structure directing agent and titanium isopropoxide as Ti source was employed. In earlier studies the critical synthesis step was found to be the removal of the organic template from the catalyst, which often destroyed the mesostructure and resulted in significant decrease in the specific surface area of the product. Therefore, novel low-temperature surfactant elimination procedures such as ozone treatment at 150°C or solvent extraction combined with ozone treatment have been systematically tested and compared to find how the textural properties of the product can be preserved ensuring the total removal of the block copolymer. The products were characterized by transmission electron microscopic (TEM), Fourier transform infrared (FT-IR), X-ray powder diffraction (XRD), thermogravimetry/derivative thermogravimetry/differential thermoanalysis (TG/DTG/DTA) and BET methods. Specific surface areas of over 500m2/g were achieved in the template free materials, and both the pore size and the anatase content were found to depend on the method of template removal and thermal treatment. The subsequent calcination applied to get higher crystallinity and higher photocatalytic activity resulted in structure collapse and surface area reduction. The catalytic performance of the samples was characterized by determining the apparent rate constant of the heterogeneous photocatalytic degradation of phenol and was found to depend not only on the anatase content, but also on the conditions of the synthesis. The characteristics of the samples prepared by us were compared with those of the commercially available Hombikat TiO2 photocatalyst. [Copyright &y& Elsevier]

Photoactivity of TiO2 photocatalyst for phenol decomposition was enhanced through its modification by the mounting of iron. Two types of Fe-C-TiO2 photocatalysts were prepared, the one having the high content of carbon, around 7.5–15.5 mass% (obtained from carbonization of poly(ethylene terephthalate) (PET)), and the other, contained the residual carbon, 0.2–3.3 mass% (obtained from the carbonization of oxalate). Photodecomposition of phenol on these Fe-C-TiO2 photocatalysts proceeded through the photo-Fenton reactions and was faster on the photocatalysts with the residual carbon, which had high content of iron. The adsorption of phenol was higher on the photocatalysts having the high content of carbon. On Fe-TiO2, the phenol decomposition was accelerated insignificantly by comparison with the pristine TiO2. It was proved that different mechanisms of phenol decomposition occurred on Fe-TiO2 and Fe-C-TiO2, on the former the phenol was decomposed by the radical reaction and on the latter by the complex reaction with the iron and intermediates of phenol decomposition. The radical reaction on Fe-TiO2 photocatalyst is not selective for phenol decomposition, therefore phenol has been decomposed slowly. By the complex reactions of phenol oxidation on Fe-C-TiO2 photocatalysts, the rate of phenol decomposition is sped up significantly, resulting in the complete mineralization of phenol in a very short time. [Copyright &y& Elsevier]

The degradation of phenol and its chlorinated derivatives with ozone is studied. The studied compounds are phenol (Ph), 4-chlorophenol (4-CPh) and 2,4-dichlorophenol (2,4-DCPh). The kinetic performances of each phenolic compound and their model mixture are examined. The pH influence on the decomposition dynamics for different phenolic compounds in the range 2–12 is investigated. The increase of the decomposition rate under increasing pH was observed. In the pH range studied, phenol and chlorophenols ozonation proceeds rapidly. The UV absorbency is used for the preliminary control of the degree of decomposition. The HPLC analysis is used to identify intermediates and final products formed during ozonation. It is shown that the basic intermediates are muconic and fumaric acids, malonic and maleic acids, catechol and hydroquinone. The final products are oxalic acid and formic acid. In the case of alkaline media, the principal final product is oxalic acid. Furthermore, intermediates and final decomposition products obtained at different pH are compared. According to the results obtained, the possible mechanism of ozonation by the reaction of hydroxylation and dechloration in the early stage is proposed. The BOD 5 /COD ratio is used as a biodegradability measure for the comparison of biodegradability of initial compounds and final products composition. [ABSTRACT FROM AUTHOR]

Untreated industrial effluents invariably contain large amounts of heavy metals and organics. This paper reports the electrochemical oxidation of synthetic water containing 200 ppm of phenol. Studies have been carried out in a compartmentalized cell using platinum (cathode) and graphite (anode). Electrolysis has been done for 40 h at constant applied potential of 5 V in different electrolytes, such as, NaCl (aq), NaOH (aq) and a mixture containing both NaCl (aq) and NaOH (aq) as the anolyte and acid as the catholyte. Phenol concentration decreased from the initial value of 200 to about 10 ppm.; the corresponding COD values, respectively, are ∼400 to ∼100 ppm. The reaction goes through chloro-compounds as intermediates before being mineralized. The carbon anode seems to be passivated with a thin layer of poly-phenol. A concomitant amount of hydrogen is generated during the electrolytic degradation of phenol. [ABSTRACT FROM AUTHOR]

• Study of appearance for TiO 2 nanoparticles possessing rutile phase. • X-ray structure analysis of TiO 2 nanoparticles possessing rutile phase. • Investigation of the light absorption and radiation of TiO 2 nanoparticles possessing rutile phase. • Study of the dependence of pH on photochemical dissociation in phenol + TiO 2 system. In this article, photochemical dissolution of phenol solution was carried out by ALDKIT001 reactor in the presence of TiO 2 nanoparticles possessing rutile phase, the physical and chemical properties of these nanoparticles have been investigated. Photochemical dissociation in the UV field was performed using a Varian device. Photochemical decomposition of phenol was confirmed by gas chromatographic mass spectroscopy. Therefore, we carried out the decomposition of phenol by photochemical reactions using rutile phase TiO 2 nanoparticles to purify phenol from wastewater. After photolysis process, 99% phenol decomposition has been occurred. Image, graphical abstract [ABSTRACT FROM AUTHOR]