聚乙烯醇微球预涂动态膜的制备及表征 |
摘要点击 2710 全文点击 2473 投稿时间:2008-08-08 修订日期:2008-11-13 |
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中文关键词 预涂动态膜 清水过滤阻力 亲水性 Zeta电位 抗污染性 |
英文关键词 pre-coated dynamic membrane pure water permeation resistance hydrophilicity Zeta potential anti-fouling characteristics |
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中文摘要 |
为了提高微滤膜的抗污染性和降低膜组件的价格,利用循环预涂工艺制备出新型聚乙烯醇微球预涂动态膜(PVA-MS/PCDMs).对不同聚乙烯醇微球预涂量的动态膜进行了系统表征,结果显示,PVA-MS/PCDMs的清水过滤阻力介于0.64×1010~3.84×1010 m-1, 渗透性良好;当预涂量≥23.9 g·m-2时,可达到微滤分离水平;亲水性随预涂量的增加而增强,动态接触角由基膜的118.25°降低到预涂量为61.9 g·m-2时的61.52°;利用流动电位法在20℃,pH为8.0±0.2,0.01 mol·L-1 KCl溶液的测试条件下,测得当预涂量为15.7 g·m-2时膜面相对Zeta电位值可达-36.4 mV.并且,通过PVA-MS/PCDMs在SMBR中的短期通量衰减变化(恒压)和对EPS的扩散实验发现,预涂量为23.9~61.9 g·m-2时,增加了对EPS的扩散渗透性能,且膜通量衰减趋于稳定时仍为基膜的3.5~4.8倍,即提高了抗污染性. |
英文摘要 |
To alleviate membrane fouling and reduce the price of membrane module, polyvinyl alcohol microsphere pre-coated dynamic membranes (PVA-MS/PCDMs) were investigated detailedly. It was prepared when the polyvinyl alcohol microsphere of the pre-coated reagent deposited on the surface and entered the pores of porous substrate common filter cloth which was low-cost by means of circulatory filtration. The morphology and structure of PVA-MS/PCDMs were examined using scanning electron microscope (SEM), and approximate maximal separated aperture, water contact angle, pure water permeation resistance and relative Zeta potential of the membrance surface were also determined. The results showed that pure water permeation resistance of PVA-MS/PCDMs was between 0.64×1010 m-1 and 3.84×1010 m-1 and the approximate maximal separated aperture reached microfiltration level. The hydrophilicity of PVA-MS/PCDMs increased with increasing PVA-MS pre-coated mass. The relative Zeta potential of the PVA-MS/PCDMs, which were measured using 0.01 mol·L-1 KCl solution, pH 8.0±0.2 and at 20℃, reached a peak value of -36.4 mV with pre-coated mass of 15.7 g·m-2 PVA-MS on the membrance surface. In addition, evolutions of PVA-MS/ PCDMs flux versus time were investigated using a 4 hours short-term filtration experiment at 9.5 kPa in an SMBR and the permeability coefficient of PVA-MS/PCDMs were measured by the extracellular polymeric substances (EPS) diffusion experiments. Results indicated that the PVA-MS/PCDMs presented dramatically high anti-fouling characteristics when the pre-coated mass of PVA-MS was 23.9-61.9 g·m-2. |