对纳滤膜分离净化湿法磷酸溶液影响因素的研究

Study on the Influence Factors of Separation and Purification of Wet-Process Phosphoric Acid Solution by Nanofiltration Membrane

选择NP010和NP030两种纳滤膜对含MgSO_(4)、Fe_(2)(SO_(4))_(3)、Al_(2)(SO_(4))_(3)的磷酸溶液进行分离净化试验,考察了盐含量、操作压力、料液温度等对纳滤膜分离性能的影响。结果表明:随盐含量的增大,纳滤膜的通量减小,其对盐的截留率亦下降;随操作压力的增大,纳滤膜的通量增大,截留率也随之增大,但在压力较高时,截留率增大趋势不明显;料液温度上升,纳滤膜的通量上升,截留率下降;在不同盐含量、操作压力、料液温度的条件下,两种纳滤膜对P_(2)O_(5)的截留率均在5%以内。

Two nanofiltration membranes,NP010 and NP030,are selected for separation and purification experiment on phosphoric acid solutions containing MgSO_(4)、Fe_(2)(SO_(4))_(3) and Al_(2)(SO_(4))_(3).The effects of salt content,operating pressure,and material liquid temperature on separation performance of the nanofiltration membrane are investigated.The results show that the flux of the nanofiltration membrane decreases with the increase of salt content,and the rejection rate of salt also decreases;as the operating pressure increases,the flux of the nanofiltration membrane increases,and the rejection rate also increases,but when the pressure is higher,the increase trend of the rejection rate is not obvious;as the temperature of the material liquid rises,the flux of the nanofiltration membrane increase,the rejection rate decreases;under the conditions of different salt content,operating pressure and material liquid temperature,the rejection rates of the two nanofiltration membranes for P_(2)O_(5) are both within 5%.