Photodegradation of acid red 114 dissolved using a photo-Fenton process with TiO_2

摘要

A dye acid red 114 (C.I.23635) was photochemically removed by adding ferric ion (Fe~(3+)), TiO_2 particvles, and H_2O_2 in the presence of the UV radiation. The removal rates of the acid red 114 (C.I. 23635) dye were 0.183, 0.210, and 0.233 mg/l/min when the ocncentrations of Fe~(3+) were 50,100, and 130 mg/l. The removal rate of the dye increased from 0.173, through 0.200, 0.210 to 0.260 mg/l/min when the H_2O_2 concentrations were 10,50,100, and 150 mg/l, respectively. The removal rates were 0.200, 0.207, 0.210, 0.273, and 0.293 mg/l/min when the concentrations of TiO_2 were 40, 60,100,500, and 1000 mg/l, respectively. The removal rate at pH 2.5 was higher than any other; pH 3.5, 5.5, and 8.5 and the phtoodegradation efficiency increased with the flow rate of air in the range from 1 to 10 l/min. From these results, relationships between the removal rate and the concentration of added Fe~(3+), H_2O_2, and TiO_2 could be expressed as the following second-order equations, respectively, R_(removal) = 3 X 10~(-6) X (C_(Fe~(3+)))~2 + 5 X 10~(-5) X (C_(Fe~(3+))) + 0.1729; R_(removal) = 2 X 10~(-6) X (C_(H_2O_2))~2 + 2 X 10~(-3) X (C_(H_2O_2)) + 0.1759; and R_(removal) = -1 X 10~(-7) X (C_(TiO_2))~2 + 2 X 10~(-4) X (C_(TiO_2)) + 0.1867.