dc.description.abstract | The textile industry in Taiwan has been developed over 50 years, and it created high economic value for many years. Textiles plays an important role in apparel industry, because of the ability for moving towards high value-added products. Unfortunately, human appealing and wear glamorous clothes have ended up causing harm to the environment. The textile industry is one of the most pollutants releasing industries of the world. Most of primary and secondary treatment processes can deal with wastewaters. However, textile dyeing wastewater which containing versatile components, including many aerosols, high chroma, high BOD and COD, it lead difficult to remove textile dyeing wastewater only by use primary and secondary treatment. Therefore, it’s important to create a novel way to treat textile dyeing wastewater.
In this study we use Fenton-like reaction to create hydroxyl radicals which are among the strongest oxidizing agents and are able to decolourise a wide range of dyes. For Fenton-like reactions we selected Chungli laterite as the iron source, which has been recognized that Fe(OH)2+ can lead to the formation of hydroxyl radical (HO∙) and Fe(Ⅱ) through a ligand-to-metal charge transfer pathway. Our investigation reveals that dye in water not only decolourisation by Fenton-like reaction but also adsorption by laterite. Meanwhile, it was observed that dyes adsorped by laterite result in low Fenton-like reaction efficiency. Additional experiments were carried out using calcination laterite by 400 degrees Celsius and 700 degrees Celsius, where Fenton-like reactions were characterized with different pH, H2O2 dosage and reaction time. Results demonstrated that the 400 degrees Celsius calcination laterite was the most effective matrix for Fenton-like reaction. It’s also show that the most effective to dyes decolourise was crystal violet. We also pressed laterite as a cake for the re-use of Fenton-like reaction, and the effective to decolourise crystal violet is still more than 75% after four times reused. Our study may offer the possibility of the great potential applications of the calcination laterite in wastewater treatment areas especially for those containing compounds which are not easy to remove by traditional treatment processes. | en_US |