Dobosz Kerianne M, Kuo-Leblanc Christopher A, Bowden Jared W, Schiffman Jessica D
Department of Chemical Engineering University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States.
Ind Eng Chem Res. 2021 Jun 30;60(25):9179-9188. doi: 10.1021/acs.iecr.1c01332. Epub 2021 Jun 17.
In this study, we systematically investigated the flux performance of ultrafiltration (UF) membranes functionalized with randomly-accumulated nanofibers. By electrospinning nanofibers from hydrophobic polysulfone (PSf) and hydrophilic cellulose (CL), we were able to explore the role that bulk nanofiber (NF) layer thickness, individual NF diameter, and intrinsic chemistry have on composite membrane flux. Additional parameters that we systematically tested include the molecular weight cut-off (MWCO) of the base membrane (10, 100, and 200 kDa), flow orientation (cross-flow versus dead-end), and the feed solution (hydrophilic water versus hydrophobic oil). Structurally, the crosslinked PSf nanofibers were more robust than the CL nanofibers, which lead to the PSfNF-UF membranes having a greater flux performance. To decouple the structural robustness from the water affinity of the fibers, we chemically modified the PSf fibers to be hydrophilic and indeed, the flux of these new composite membranes featuring hydrophilic crosslinked nanofibers were superior. In summary, the greatest increase in flux performance arises from the smallest diameter, hydrophilic nanofibers that are mechanically robust (crosslinked). We have demonstrated that electrospun nanofiber layers improve the flux performance of ultrafiltration membranes.
在本研究中，我们系统地研究了用随机堆积的纳米纤维功能化的超滤（UF）膜的通量性能。通过从疏水性聚砜（PSf）和亲水性纤维素（CL）静电纺丝纳米纤维，我们能够探究整体纳米纤维（NF）层厚度、单个NF直径和固有化学性质对复合膜通量的作用。我们系统测试的其他参数包括基膜的截留分子量（MWCO）（10、100和200 kDa）、流动方向（错流与死端）以及进料溶液（亲水性水与疏水性油）。在结构上，交联的PSf纳米纤维比CL纳米纤维更坚固，这导致PSfNF-UF膜具有更高的通量性能。为了将结构坚固性与纤维的水亲和力解耦，我们将PSf纤维化学改性为亲水性，实际上，这些具有亲水性交联纳米纤维的新型复合膜的通量更高。总之，通量性能的最大提升来自于直径最小、亲水性且机械坚固（交联）的纳米纤维。我们已经证明，静电纺丝纳米纤维层可提高超滤膜的通量性能。
