Application of microfibrillated fibers in robust and reusable air filters with long service time in the ambient with high oily aerosols concentration

There are two challenges in the application of dual-layer structured nanofibers composite filters (1) they tend to deteriorate easily during the air cleaning process for reuse; (2) their service time under the condition with high oily aerosol concentration is only half of that under the condition with pure solid particles. In this study, fibrillated fibers are used to fabricate robust dual-layer structured air filters. The influence of the content of fibrillated fibers in the filters on their performance is studied. Their performance is compared with a kind of commercial electrospinning nanofibers composite filters that had similar initial filtration efficiency. They have longer service time than the commercial filters contributing to their longer duration and lower residual pressure drop of the cleaning cycles. They are more robust than the commercial filters. Their dust holding capacity against the diisooctyl sebacate (DEHS)-A2 dust mixture with different DEHS content is 1.6 to 5.1 times that of the commercial filters. This study indicates that fibrillated fibers can be utilized to develop robust and reusable filters with a long service time, especially in harsh conditions with abundant oily aerosols.