Nanofiber Filter Performance Improvement: Nanofiber Layer Uniformity and Branched Nanofiber

We developed two types of high performance nanofiber filters by increasing the uniformity of the fiber layer's deposition on the substrate media and by fabricating nanofiber with a branched morphology, in which additional fibers were spun to radiate from the main fibers. We subsequently compared them with conventional and beaded nanofiber filters in terms of particle removal efficiency, filter pressure drop, and particle loading capacity. First, the uniformity of the nanofiber's deposition, which was visually evaluated using optical and electron microscopes, was increased by removing the substrate surface charge during electrospinning. The uniform nanofiber filters demonstrated a higher filtration efficiency with a lower pressure drop than their conventionally electrospun counterparts, which exhibited irregular fiber layers. Second, branched nanofiber was fabricated by adjusting the viscosity of the polymer solution. The performance of the nanofiber filters was dramatically improved by the decrease in air flow resistance, which resulted from (1) a longer distance streamwise between the fibers and (2) a smaller diameter for the fibers. The enhanced efficiency was also due to (3) the additional fibers branching out from the main fibers.

我们通过增加纤维层在基材介质上沉积的均匀性并通过制造具有分支形态的纳米纤维来开发两种高性能的纳米纤维过滤器，其中纺出了额外的纤维以从主纤维中辐射出来。随后，我们在颗粒去除效率，过滤器压降和颗粒负载能力方面将它们与常规和串珠纳米纤维过滤器进行了比较。首先，通过去除静电纺丝过程中的基板表面电荷，提高了纳米纤维沉积的均匀性，这种均匀性是使用光学和电子显微镜目测评估的。均匀的纳米纤维过滤器比常规电纺丝过滤器表现出不规则的纤维层，显示出更高的过滤效率和更低的压降。第二，通过调节聚合物溶液的粘度来制备支化纳米纤维。纳米纤维过滤器的性能通过降低空气流动阻力而得到显着改善，这是由于（1）纤维之间的流向距离较长以及（2）纤维的直径较小。效率的提高还归因于（3）其他纤维从主纤维分支出来。

Published: 2020

Journal ：Aerosol and Air Quality Research

Impact Factor：2.735

Paper link: https://aaqr.org/articles/aaqr-19-07-oa-0343