A new approach for statistical optimization in synthesis of titanium dioxide nano particles and evaluating the environmental application of optimized product

Amir Bagheri Garmarudi^1,2[*], Mohammadreza Khanmohammadi¹ , Nafiseh Khoddami¹

1-      Chemistry Department, Faculty of Science, IKIU, Qazvin, Iran

2-      Department of Chemistry & Polymer Laboratories, Engineering Research Institute, Tehran, Iran

Email: a.bagheri@ikiu.ac.ir

The use of semiconductor oxide particles as photocatalysts is well established and has shown great utility in the complete mineralization of organic pollutants. Among these photocatalysts, TiO₂ nano structure has been proved to be an excellent catalyst in the photocatalytic degradation of organic pollutants, because it is an effective, photo stable, reusable, inexpensive, non-toxic and easily available catalyst.

Different forms of TiO₂, such as thin and thick film coatings, powders, and membranes have been utilized to make this catalyst more efficient and more applicable. Previous studies have indicated that the method of TiO₂ photocatalyst production and its physical form are among the most determining parameters influencing the overall photo-efficiency. There are several routes, introduced for synthesis of titanium dioxide nano particles and sol-gel is one of the main researched techniques. Sol–gel processing is a common chemical approach to produce high purity materials shaped as powders, coatings, fibers, monoliths, and self-supported bulk structures. The main issues, affecting the particle size and catalytic efficiency would be the stoichiometric portions of chemical, aging condition and sintering. Through controlled hydrolysis and polycondensation reactions of a precursor (e.g. metal alkoxide) a three dimensional network structure can be developed in the form of a gel. Subsequent drying and calcinations steps may result in an oxide structure, which consolidates at sintering temperatures much lower than that of materials derived from conventional methods. It was tried to optimize the effective parameters in synthesis of nano TiO₂ in order to achieve the best results in particle size. Analysis of variance (ANOVA) was applied for this aim. ANOVA is a useful technique for comparing more than two methods or treatments. The variation in the sample responses (treatments) is used to decide whether the sample treatment effect is significant. Analysis of variance ANOVA is similar to regression in that it is used to investigate and model the relationship between a response variable and one or more independent variables. Finally the photocatalytic activity and efficiency of the optimized nano structure was also investigated via degradation monitoring of organic pollutant in environmental samples e.g. waste water.   

Keywords: optmization, environmental, analysis of variance, titanium dioxide