10th International Aerosol Conference
September 2 - September 7, 2018
America's Center Convention Complex
St. Louis, Missouri, USA

Abstract View


Adsorption Characteristics of Sub-10nm Nanoparticles on Porous Materials

ZIYI LI, Yingshu Liu, Chuen-Jinn Tsai, Yi Xing, Pei Lu, Likun Yin, Ralph Yang, University of Science and Technology Beijing

     Abstract Number: 331
     Working Group: Control and Mitigation

Abstract
Adsorption of tiny nanoparticles with sizes close to gases on porous materials, such as activated carbons and zeolites, has been a long-existed and unrevealed issue in the gas separation field. Several recent studies dealing with PM2.5 using activated carbons (Kim et al., 2016), MOFs-coated filters (Chen et al., 2017), and nanofiber-coated window screens (Khalid et al., 2017) have shown functions of porous structure in trapping particles, and thus the lack of consideration on filter material effects for predicting filtration efficiency at nanometer range based on traditional theory. On the other hand, nanoparticles behaving like gas molecules are able to easily diffuse deep into porous networks, which would influence the utilization of adsorbents in practical gas separation (Kim et al., 2017), and needs theoretical directions for protection.

Herein, we demonstrate this particular phenomenon by conducting the removal efficiency test for sub-10 nanoparticles filtered by mesoporous adsorbents with different morphologies, including CMK-3, CMK-5, KIT-6, and a series of SBA-15 with the primary pore size range of 5.8-17.8 nm, and by FAU zeolites ion-exchanged with different cations such as Li+, Na+, K+, Mg2+, Ca2+ and Sr2+. The results show efficiency curves different from those predicted by Brownian diffusion filtration theory which always get close to 100% below 10nm, and varied in a regular manner with adsorbent properties. The effects of morphologies, pore size distributions and ion exchange properties on nanoparticle capture will be explored in details based on material characterizations, adsorption theories, and molecular simulations.

Keywords: nanoparticles, porous materials, adsorption, removal efficiency test, molecular simulation

Reference:

Chen, Y., Zhang, S., Cao, S., Li, S., Chen, F., Yuan, S., Xu, C., Zhou, J., Feng, X., Ma, X., & Wang, B. (2017). Roll‐to‐Roll Production of Metal‐Organic Framework Coatings for Particulate Matter Removal. Advanced Materials, 29(15).

Khalid, B., Bai, X., Wei, H., Huang, Y., Wu, H., & Cui, Y. (2017). Direct blow-spinning of nanofibers on a window screen for highly efficient PM2. 5 removal. Nano letters, 17(2), 1140-1148.

Kim, C., Kang, S., & Pui, D. Y. (2016). Removal of airborne sub-3 nm particles using fibrous filters and granular activated carbons. Carbon, 104, 125-132.

Kim, C., Lee, H., Juelfs, A., Haynes, C. L., & Pui, D. Y. (2017). The effect of filtered nanoparticles on gas filtration efficiency of granular activated carbons. Carbon, 121, 63-71.