Degradation of formaldehyde by UV/Titanium dioxide process

Abstract

Photocatalysis by UV/Titanium dioxide process was evaluated for the degradation of the synthetic formaldehyde solution using a lab scale-batch reactor. The effects of titanium dioxide dosage, pH of mixture solution, and initial concentration of formaldehyde were systemically studied. The highest efficiency of formaldehyde degradation was achieved with the dosage of titanium dioxide 0.1 g/l. At the larger dosage, an excess amount would inhibit the transimission of light and furtherly caused decreasing in removal efficiency. Additionally, both pH and the initial concentration of formaldehyde in mixture solution affected the efficiecy removal. The photocatalytic of formaldehyde degradation was favored under an acidic condition at pH 3 and decreased with increasing initial formaldehyde concentration. The reduction of toxicity and Total Organic Carbon were also investigated because the total mineralization is an important criteria in assessing the feasibility of this process for formaldehyde degradation. The toxicity reduction below EC50 was only attained when the initial concentration was less than 3,000 mg/l