| Summary: | 碩士 === 國立臺灣大學 === 環境工程學研究所 === 89 === The objective of this study is to remove 2-Naphthalenesulfonic acid sodium (2-NSAS) by ozone (O3) or ozone/ultraviolet (UV) in the aqueous solution and acid-based electroplating solution of printed circuit board (PCB) industry. The substrates (the major chemical species) of the electroplating solution recipe are inorganics, such as sulfuric acid, copper sulfate, etc., which will not be reacted by O3 or O3/UV. Ozonation will only destroy the minor organic additives (2-NSAS, for example).
The study establishes the kinetic expression of O3 mass transfer, O3 self decomposition , and O3/UV decomposition in deionized water by batch and semi-batch experiments. The results indicate that the O3 surface mass transfer coefficient = 0.000537 s-1, and the O3 bubble mass transfer coefficient = 0.0201 s-1, and the self-decomposition rate of O3 = 0.00014 s-1 CALb, and the self-decomposition rate of O3 with UV = 0.0108 m2W-1s-1[ Iuv ]CALb. The study uses a two-step reaction mechanism to simulate the kinetic of ozonation of 2-NSAS in the deionized water. Besides, the kinetic of ozonation of 2-NSAS in the deionized water of semi-batch system can be simulated in terms of CALb, CBLb, CTOC ,and SO42-. The rate constants are estimated by comparing the simulation results with the experiment data. The trial-and-error and fourth-order Runge-Kutta methods whih C program are used. The employed UV light intensity [ Iuv ] in the O3/UV reaction are 27.01, 33.46, 35.96, and 62.98 W/m2. The initial concentration of 2-NSAS is 200.0 mg/L, which is equivalent to TOC of 104.2 mg/L.
The obtained kinetic parameter (rate constants and reaction orders) from above are used in predication of ozonation of 2-NSAS for semi-batch experiments. In the semi-batch O3/2-NSAS experiments in deionized water, the percentile of TOC removal is about 94 % as the ozone dosage in each liter of deionized water (mO3) = 23.1 mg/min．L and ozonation time ( t ) = 180 min. As for the semi-batch O3/UV/2-NSAS experiments in deionized water, the percentile of TOC removal raises to 100 % when [ Iuv ] = 62.98 W/m2, as the ozone dosage in each liter of deionized water (mO3) = 21.0 mg/min．L and ozonation time ( t ) = 60 min. In the semi-batch O3/2-NSAS experiments in acid-based electroplating solution, the percentile of TOC removal is about 89.6 % as the ozone dosage in each liter of electroplating solution (mO3) = 21.0 mg/min．L and ozonation time ( t ) = 180 min. As for the semi-batch O3/UV/2-NSAS experiments in acid-based electroplating solution, the percentile of TOC removal can raise 10 % averagely when [ Iuv ] = 62.98 W/m2, as the ozone dosage in each liter of electroplating solution (mO3) = 21.0 mg/min．L and ozonation time ( t ) = 180 min.
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