Summary: | 碩士 === 國立中興大學 === 化學工程學系所 === 101 === In this study, a mixture of 30 wt% plant waste particles (e.g. tea leaves, banana peel, shaddock peel, and water bamboo husk) with polymer (e.g. polyethersulfone or polyethylene terephthalate) was blended to prepare the porous mixed matrix membranes (MMMs) for the removal of dyes from water. The plant waste particles had the diameter of 45-100 μm and zeta potential of banana peel and water bamboo husk were 1.5 and 2.5, the other particles(tea leaves and shaddock peel) were bring negative charge at any pH values. The prepared MMMs had the pore size of 0.5-3 μm, water content of 45-55%, and ion exchange capacity of 600-620 μmol/g membrane. The batch adsorption process of cationic dyes (methylene blue and methyl violet 2B) was conducted at room temperature and pH 4. The MMMs achieved an adsorption equilibrium after 8 hr, with the maximum adsorption capacities for methylene blue and methyl violet 2B at 300-340 mg/g membrane (1000-1130 mg/g particles) and 300-370 mg/g membrane (1000-1230 mg/g particles), respectively. In batch desorption, 1 N KSCN in 80% methanol was selected as the optimal desorption solution and the desorption efficiencies for MMMs were about 95%. In the flow process with 1 mL/min, the cycle of adsorption, washing, and elution was repeated to test the membrane efficiency. The loading dye concentration was 5 ppm, and one piece of MMM (bed volume of 0.07 mL) was placed in the 25 mm disc holder. The results showed that the breakthrough volumes were 5-10 mL (70-140 bed volume) and the ratios of adsorption and desorption were about 90%. The whole process could be repeated three times successfully, without any deterioration on the performance.
Keyword:Polyethersulfone、Polyethylene terephthalate、Plant waste particle、Mixed Matrix Membrane、Cationic dyes.
|