http://publicationslist.org/data/meng.chong/ref-18/sdarticle.pdf

Recent Developments in Photocatalytic Water Treatment Technology: A Review

Photoinduced reactivity of titanium dioxide

Titanium dioxide, TiO2, is an important photocatalytic material that exists as two main polymorphs, anatase and rutile. The presence of either or both of these phases impacts on the photocatalytic performance of the material. The present work reviews the anatase to rutile phase transformation. The synthesis and properties of anatase and rutile are examined, followed by a discussion of the thermodynamics of the phase transformation and the factors affecting its observation. A comprehensive analysis of the reported effects of dopants on the anatase to rutile phase transformation and the mechanisms by which these effects are brought about is presented in this review, yielding a plot of the cationic radius versus the valence characterised by a distinct boundary between inhibitors and promoters of the phase transformation. Further, the likely effects of dopant elements, including those for which experimental data are unavailable, on the phase transformation are deduced and presented on the basis of this analysis.

https://link.springer.com/content/pdf/10.1007%2Fs10853-010-5113-0.pdf

Review of the anatase to rutile phase transformation

http://repository.ias.ac.in/39608/1/49_pub.pdf

A review of imperative technologies for wastewater treatment I: oxidation technologies at ambient conditions

The need to design low-cost adsorbents for the detoxification of industrial effluents has been a growing concern for most environmental researchers. So modelling of experimental data from adsorption processes is a very important means of predicting the mechanisms of various adsorption systems. Therefore, this paper presents an overall review of the applications of adsorption isotherms, the use of linear regression analysis, nonlinear regression analysis, and error functions for optimum adsorption data analysis.

https://downloads.hindawi.com/journals/jchem/2017/3039817.pdf

Modelling and Interpretation of Adsorption Isotherms

The photocatalytic decomposition of phenol in oxygenated aqueous suspensions of lightly-reduced anatase TiO2, being the most satisfactory among the semiconductors investigated from the standpoint of the photocatalytic activity and stability, has been investigated at the optimum pH 3.5. The products at the initial stage of the reaction were hydroquinone, pyrocatechol, 1,2,4-benzenetriol, pyrogallol, and 2-hydroxy-1,4-benzoquinone. These intermediates underwent further photocatalytic oxidation via acids and/or aldehydes finally into CO2 and H2O. A reaction scheme involving hydroxyl radicals as real reactive species has been proposed. Although H2O2 was formed via O2\ewdot produced by electron trapping of adsorbed oxygen, its concentration remained constant at a low value during the reaction. About 0.7 mole of O2 was consumed for the consumption of one mole of phenol at the initial stage of the reaction. These results indicated that hydroxyl radicals were formed not only via holes but also via H2O2 from O2\ew...

Heterogeneous Photocatalytic Decomposition of Phenol over TiO2 Powder

Laser photochemistry of poly(N-vinylcarbazole) in solution

Magnetic field effect on the photoconductivity of poly-n-vinylcarbazole

The dye-sensitized photodegradation of aqueous phenol using rose bengal was carried out batchwise in the chemical region by using an annular bubble-column photoreactor, to evaluate the use of sunlight in wastewater treatment. Effects of both the partial pressure of oxygen and the initial concentration of phenol, [A]0, on the initial reaction rate were analyzed according to the reaction scheme including the quenching reaction of triplet dye 3D* with phenol, in order to determine the kinetic parameters. The reaction rate constant of phenol with singlet oxygen increased with increasing pH and was 2.66 ×108 dm3/mol-s at pH 10.3. The reaction quantum yield at pH 10.3 was limited to a maximum of 0.29 at [A]0=3 ×10-3 mol/dm3 for O2-bubbling and 0.13 at [A]0=1.4 ×10-3 mol/dm3 for air-bubbling by the quenching reaction of 3D* with phenol, of which the rate constant was 4.0×108 dm3/mol• s. p-Benzoquinone, the primary main product, underwent further degradation with both alkaline and ground-state oxygen to yield final products such as carboxylic acids. The reaction curves were simulated closely up to high conversions by taking account of the quenching effect of both phenol and the quinone-type intermediate products on 3D*.

Akira Itaya

Papers

Heterogeneous Photocatalytic Decomposition of Phenol over TiO2 Powder

Laser photochemistry of poly(N-vinylcarbazole) in solution

Magnetic field effect on the photoconductivity of poly-n-vinylcarbazole

Kinetics of dye-sensitized photo-degradation of aqueous phenol

Ionic photodissociation of some polymers quenched with electron donor or acceptor in solution