The total annual production of synthetic dye is more than 7 × 105 tons. Annually, through only textile waste effluents, around one thousand tons of non-biodegradable textile dyes are discharged into natural streams and water bodies. Therefore, with growing environmental concerns and environmental awareness there is a need for the removal of dyes from local and industrial water effluents with a cost effective technology. In general, these dyes have been found to be resistant to biological as well as physical treatment technologies. In this regard, heterogeneous advanced oxidation processes (AOPs), involving photo-catalyzed degradation of dyes using semiconductor nanoparticles is considered as an efficient cure for dye pollution. In the last two decades TiO2 has received considerable interest because of its high potential as a photocatalyst to degrade a wide range of organic material including dyes. This review starts with (i) a brief overview on dye pollution, dye classification and dye decolourization/degradation strategies; (ii) focuses on the mechanisms involved in comparatively well understood TiO2 photocatalysts and (iii) discusses recent advancements to enhance TiO2 photocatalytic efficiency by (a) doping with metals, non-metals, transition metals, noble metals and lanthanide ions, (b) structural modifications of TiO2 and (c) immobilization of TiO2 by using various supports to make it a flexible and cost-effective commercial dye treatment technology.

https://pubs.rsc.org/EN/content/articlepdf/2014/ra/c4ra06658h

Principles and mechanisms of photocatalytic dye degradation on TiO 2 based photocatalysts: a comparative overview

Fundamental principles and application of heterogeneous photocatalytic degradation of dyes in solution

An overview on the photocatalytic degradation of azo dyes in the presence of TiO2 doped with selective transition metals

There are number of water purification techniques but the adsorption is one of the most simplest, effective and economical method for wastewater purification. In this article a large number of solid adsorbents such as Natural adsorbents, Agricultural Wastes, Industrial wastes, Biomass, Nanoadsorbents: Carbon based nanomaterials, Nobel metal based nanomaterials, Metal oxide based nanomaterials, Spinel ferrite based nanomaterials, Nanocomposites, Dendritic polymers; Geopolymer cement have been discussed for the removal of different pollutants from waste water. Removal of Fluoride, Phosphate, Nitrate and Radionuclides from wastewater has also been reviewed in this article. Adsorption isotherm models, kinetic models, thermodynamic parameters and adsorption mechanism have also been discussed. The present article lists different type of adsorbents and reviews state-of-the-art of the removal of different pollutants from water. The efforts have been made to discuss the sources of contamination and toxicities of pollutants. Adsorption mechanisms responsible for pollutants removal by different adsorbents have been reviewed. Attempts have also been made to point out the advantages and drawbacks of adsorbents and the future research needs in the area of water purification by adsorbents.

Water purification by using Adsorbents: A Review

Adsorption of dyes by nanomaterials: Recent developments and adsorption mechanisms

Photocatalytic degradation of C.I. Basic Violet 10 using TiO2 catalysts supported by Y zeolite: An investigation of the effects of operational parameters

http://dns2.asia.edu.tw/~ysho/Truth/PDF/J%20Haz%20Mat147,%20997.pdf

Meng-Du Lyu

Papers

Photocatalytic degradation of C.I. Basic Violet 10 using TiO2 catalysts supported by Y zeolite: An investigation of the effects of operational parameters

Application of MCM-41 for dyes removal from wastewater.

Effects of sodium content and calcination temperature on the morphology, structure and photocatalytic activity of nanotubular titanates

Effects of synthesis temperature on the microstructures and basic dyes adsorption of titanate nanotubes.

Application of titanate nanotubes for dyes adsorptive removal from aqueous solution.