Synthesis, Characterization And Testing Of Titanium (iv) Oxide Tungsten (vi) Oxide Compound As Potential Catalysts For Water Purification
Abstract
The objective of this study was to synthesize Titanium (IV) Oxides tungsten (VI) oxide
compound and subsequently test them for use as photo catalysts in water purification. The synthesized compound was calcined at 575DC. An X-Ray Diffraction was taken for structure determination, at 2theta angles at a range of ODC- 80DC. The results showed particle size
diameter of 18.99 nm using Copper k-alpha X-Rays of 1.54060nm and Scherrer constant of 0.89.
The the compound was then tested for efficacy in photodecomposition and deactivation of chemical and microbial loads in water. Using Methyl Orange and Methylene blue dyes, the best photo catalytic efficiency on exposure to visible light and solar radiation was achieved with
synthesized compound at room temperature at a ratio of 1: I Ti: Wand 0.5g/L photo catalyst amount. The Photo catalytic decomposition of methylene blue was found to follow first order
kinetics with a t1l2of 45minutes and a reaction rate constant, k, 0.0 154 at pH 2. Reaction kinetics
fitted the Langrnuir-Hinshelwood model for pseudo first order rates.
Results on heavy metals showed a 98.77% efficiency removal of Copper (II) ions and 97.48%
removal efficiency of Lead (II) ions from water. Solid Phase Extraction was used for the analysis
of the following organochlorine pesticides; a-HCH, ~-Lindane, BHC and b-HCH. Irradiation
was done using an 8W Blacklight Blue (BLB) low pressure mercury vapor lamp from Philips
and gave results that indicated degradation for a-HCH, ~-Lindane, BHC, and b-HCH to be 95%,
91%, 98% and Below Detection Limit respectively. Results on inactivation of Escherichia Coli showed a log reduction of 3.415 corresponding to 99.9615% E.coli removal. Photo killing of total coliforms was carried out under solar illumination and the results indicated a log 2.4559 reduction corresponding to 99.6499% total coliform removal.
Citation
Master Of Science Degree In Environmental Chemistry, University Of Nairobi, 2013Publisher
University of Nairobi