Nanofiltration separation process of model glyphosate wastewater

Key words: 
• glyphosate /
• model wastewater /
• nanofiltration separation

Abstract: The nanofiltration separation of model glyphosate wastewater was investigated using DK membrane in order to study the influencing factors and variation laws. The experimental results showed that under the condition of 20℃, concentration of glyphosate 500 mg/L, pH value 2.96, glyphosate retention rate increased slightly with the increase of transmembrane pressure, while its permeate flux linearly increased with the increase of transmembrane pressure. Permeate flux increased with the increase of operation temperature, while its retention rate decreased.With feed concentration increasing, both permeate flux and glyphosate retention rate decreased. In the pH range of 3～5, glyphosate retention rate decreased with pH increasing, and reached its lowest retention rate at isoelectric point, while its permeate flux reached the highest point. And in the pH range of 5～11, glyphosate retention increased with pH increasing, and permeate flux decreased with the increase of pH. Due to the shielding phenomenon, glyphosate retention decreased with the increase of NaCl concentration.