초록
본 연구에서는 methylene blue의 오존 산화하는 동안 BOD, COD, TOC, 흡광도 그리고 탈색 비율을 분석하였으며, 오존산화반응은 methylene blue가 충진되어 있는 원형모양의 반응기에서 수행한 결과 다음과 같은 결론을 얻었다. 탈색도는 최대파장(${\lambda}_{max}$, 660 nm)에서 흡광도를 측정하였다. 오존농도는 $50{\pm}10mg/L$를 사용하였으며 40 min 후 거의 오존산화반응이 끝났다. 그 결과로 $30^{\circ}C$에서 오존산화 반응 후 $TOC/TOC_0$ 비율은 83.8%로 나타났고, COD는 초기값보다 44.0% 감소하였다. 그리고 $BOD_5/COD$ 비율은 64.2%에서 90.8%로 오존산화 반응 후 생분해도가 증가하는 것으로 나타났다. 반응속도상수는 $3.30{\times}10^{-2}min^{-1}$로 나타났으며, 활성화 에너지는 $3.01kcal{\cdot}mol^{-1}$로 나타났다.
In this study treatment efficiencies of methylene blue were evaluated in term of BOD, COD, TOC, absorbance and initial decolorization rates. Ozonation of the dye in distilled water was performed in a laboratory scale cylindrical batch reactor. The decolorization process of methylene blue was carried out by bubbling ozone at the bottom of a bubble column reactor containing the dye solution. Decolorization, determined by measuring the light absorbance at the maximum wavelength in the (${\lambda}_{max}$, 660 nm), was almost complete after 40 min with an ozone concentration of $50{\pm}10mg/L$. The $TOC/TOC_0$ ratio after ozonation was about 83.8%, the COD was diminished to 44.0% of the initial value. The $BOD_5/COD$ ratio was increased from 64.2% to about 90.8%, indicating an enhancement of biodegradable compounds in the ozonated solutions. The pseudo first-order rate constants of the ozonation was $3.30{\times}10^{-2}min^{-1}$ and the activation energy was $3.01kcal{\cdot}mol^{-1}$ at $30^{\circ}C$.