College of Environment, Nanjing University of Technology, Nanjing, Jiangsu, China.
Water Sci Technol. 2012;65(5):816-22. doi: 10.2166/wst.2012.808.
Nanofiltration separation of glyphosate simulated wastewater was investigated using a DK membrane. The effects of operating parameters and the addition of impurities on membrane performance were studied in detail. It was found that at 20 °C, with a glyphosate concentration of 500 mg/L and pH of 2.96, the glyphosate retention rate and the membrane permeate flux increased slightly with increasing transmembrane pressure. With an increase in operating temperature, the permeate flux increased linearly while the retention rate decreased. The permeate flux and glyphosate retention rate decreased with increasing feed concentration. Within the pH range of 3-5, the glyphosate retention rate decreases with increasing pH and reaches a minimum at the isoelectric point of the membrane, while the permeate flux reaches a maximum level at this point. In the pH range of 5-11, with the increases of pH, the glyphosate retention rate increases and the permeate flux decreases. Glyphosate retention decreases slightly with increasing NaCl and phosphite concentrations. This can be explained in terms of the shielding phenomenon.
采用 DK 膜对草甘膦模拟废水进行纳滤分离，详细研究了操作参数和杂质添加对膜性能的影响。结果表明，在 20°C、草甘膦浓度为 500mg/L、pH 值为 2.96 时，随着跨膜压力的增加，草甘膦截留率和膜渗透通量略有增加。随着操作温度的升高，渗透通量呈线性增加，而截留率降低。随着进料浓度的增加，渗透通量和草甘膦截留率降低。在 3-5 的 pH 范围内，草甘膦截留率随 pH 的增加而降低，并在膜等电点达到最低，而此时渗透通量达到最高水平。在 pH 5-11 范围内，随着 pH 的增加，草甘膦截留率增加，渗透通量降低。草甘膦的截留率随 NaCl 和亚磷酸盐浓度的增加略有降低。这可以用屏蔽现象来解释。
