超滤操作条件对酸性红染料提纯过程的影响

Effect of UF operating conditions on purification process of Acid Red

采用超滤膜技术对染料酸性红的提纯过程进行研究.分别考察操作压力、料液流量及料液浓度对超滤膜分离行为的影响.实验过程选用截留相对分子质量分别为5 000和10 000的两种超滤膜,结果表明,在0.15～0.4MPa的操作压力范围内,随着操作压力的增加,两种超滤膜的透过液通量增大,对杂质截留率增大,而对染料的截留能力略有下降;在10～30m3/s的料液流量范围内,随着料液流量的增大,截留相对分子质量5 000的超滤膜透过液通量增大,杂质截留率增大,对染料的截留能力则变化不大,而截留相对分子质量为10 000的超滤膜的透过液通量、杂质截留率和染料截留能力均与料液流量关系不大;在质量分数0.5%～4%的料液浓度范围内,随着料液浓度的增大,两种超滤膜的透过液通量、杂质截留率和染料截留率均下降.研究认为,对截留相对分子质量10 000的超滤膜,膜孔堵塞是影响膜性能的主要因素因素;而对截留分子量5 000的超滤膜,膜面产生的凝胶层则是影响其性能的主要因素.

A soluble dye Acid Red was purified by a UF process. The effects of operating pressure, flux of feed solution and feed concentration on the separation process of UF membranes were studied. Two kinds of UF membranes with molecular weight cut-off value 5 000 and 10 000 respectively were selected in the experiments, and the results showed that the permeation flux and impurities rejection of two UF membranes increased with the increase of operating pressure in the range of 0. 15 MPa to 0. 4 MPa, while the dye rejection of two UF membranes decreased slightly at the same time. The permeation flux and impurities rejection of UF membrane MWCO 5 000 increased with the increase of feed flux in the range of 10 m^3/ s to 30 m^3/s, while the dye rejection of UF membrane MWCO 5 000, the permeation flux, impurities and dye rejection 0f UF membrane MWCO 10 000 were unchangeable. The permeation flux, impurities and dye rejection of two UF membranes decreased with the increase of feed concentration in the range of 0. 5% to 4 %. In addition, the pore-clogging was the main factor affecting the performance of UF membrane MWCO 10 000, while the gel layer formation on the membrane surface was the main factor affecting performance of UF membrane MWCO 15 000.