A study of mechanism and factors for Iron to activate persulfate in pollutant degradation

• Main Authors: Ting-Ru Chen, 陳亭如
• Other Authors: Jao-Jia Horng
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/23735654027712969294

碩士 === 國立雲林科技大學 === 環境與安全衛生工程系 === 102 === Chemical oxidation methods was commonly used in soil and groundwater remediation traditionally, mostly Fenton was the most common one. The use of ferrous ions reacted with hydrogen peroxide to generate strong oxidizing hydroxyl radicals to degrade pollutants. But, Fenton application need to be at low pH conditions. Therefore, this study added another oxidizer, persulfate, to degrade pollutants Acid Orange 7 (AO7) dyes and oil-like to study their enhancing effects & influence factors. In this study, hydrogen peroxide, persulfate and Ferrous ions were combined to study their reaction mechanisms. Using electron paramagnetic resonance spectroscopy (ESR) with DMPO (5,5-Dimethyl-1-pyrroline N-oxide) to detect the generatation of the radical, the Taguchi method was used to find the optimal conditions. At temperature 20℃, pH5, the conditions of hydrogen peroxide 1 × 10-4 M, persulfate 10 × 10-4 M and ferrous 8 × 10-4 M were tested to be the best for AO7 degradation of 80%. All types of catalyst means (UV > Ferrous > Ferrous+Ultrasonic > TiO2+UV > Ultrasound > TiO2) coukd degrade various dyes well. Finally, the optimum condition that were used for toluene pollutant in the soil also showed good degradation effects. This study showed that the addition of persulfate not only yielded good degradation but also exceed the traditional Fenton method which required low pH.