A new low-cost method for the removal of agricultural pesticides from water by titanium dioxide photocatalyst was introduced by Iranian researchers at University of Tabriz.
"We synthesized titanium dioxide nanoparticles of 6 to 11 nanometers by controlled hydrolysis of TiCl4 solution in both anatase and rutile phases. We studied the removal of Bentazon herbicide in the presence of TiO2 nanoparticles as photocatalyst and under UV-C irradiation and analyzed a number of determining factors in this process," Dr. Alireza Khataee, one of the researchers, said in an interview with the news service of Iran Nanotechnology Initiative Council.
"We also elaborated the kinetics of Bentazon herbicide removal by Langmuir-Hinshelwood model", Khataee added.
Noting that in the controlled hydrolysis method, it is possible to synthesize TiO2 nanoparticles in anatase, rutile, or amorphous form by controlling the conditions, he reiterated that the Anatase form of TiO2 has better photocatalytic properties than rutile one and calcinating its nanoparticles enhances photocatalytic properties through improving crystals quality.
"The results imply that using synthesized nanocatalysts shows better performance than their commercial type in removing Bentazon herbicide from contaminated waters," Khataee said.
He also mentioned that the organic derivatives of titanium have been used for the synthesis of TiO2 nanoparticles in most of the previous works whereas in the present study "we used TiCl4 as raw material".
Considering the high price of titanium organic derivatives and the fact that TiCl4 is one of the intermediate components in industrial production of TiO2 by chloride method, it seems promising to industrialize the present method with no problem.
The details of this research are published at Desalination, volume 249, pages 301-307, 2009.