Summary: | 碩士 === 國立清華大學 === 生醫工程與環境科學系 === 101 === In recent years, industrial wastewater is a major source of metal polluting in the environment. However, there is still no effective way to remove heavy metal in the wastewater. In addition, pretreatment processes such as ion exchange and solvent extraction suffer from the secondary pollution caused by the spent resins/solvent. In this study, membrane filtration techniques to remove trace metals and spent resins/solvent in the simulated wastewater Co, Sr and Cs are selected to evaluate the chelating ability of APDC. The results show that the selectivity of APDC is in the following order: Co >> Sr> Cs. Through the LA-ICP-MS and α-step profilometer measurement, the obtained results are consistent with fouling mechanisms based on Hermia model and reveal that the chelating complex could be used as a tracer to demonstrate the phenomenon of organic fouling in the membrane filteration.. Thus Co is chosen to explore the complexation ability of different organics (APDC, LAS, SDS and CTAB) as well as a tracer to present the spatial distribution of organics on the membrane surface. The results show that the distribution of S and Co in the APDC-Co sample has high correlation (R2 = 0.9402) and reveals strong affinity between APDC and Co. The ultrasonic imaging system is also conducted to investigate the depth/ roughness of membrane surface before and after the foulant removing by different chemical agents (water, 2% HCl and 1M NaOH)).
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