High resolution imaging and image analysis in porous media

Yalçın, Özge Hande
Flow and mass transfer in porous media are intimately coupled to their microstructure. Advances in computational capabilities have brought about the possibility of modeling these materials by employing the high-resolution 3D topography in flow and mass transfer simulations. This work investigates and analyzes the microstructure and adsorbate localization behavior of porous media. Specifically, high- resolution microscopy techniques were implemented to obtain morphology information for porous media. Gigacap Q-650M and HALOTM were chosen as adsorbents and α-lactalbumin was used as staining protein. Microstructures of Gigacap Q-650M and HALOTM were imaged by using Scanning Electron Microscopy (SEM). The crosslinking structure of Gigacap Q-650M was observed, and the core-shell structure of HALOTM particle was also investigated by using SEM. Gigacap Q-650M with and without adsorbed protein were characterized by Transmission Electron Microscopy (TEM). Contrast in the protein-loaded adsorbent was much better than the sample without adsorbed protein. In TEM images, protein localization on the adsorbent was investigated. It can be surmised that the protein on Gigacap Q-650M remains confined to polymethyl methacrylate (PMMA) base and aldehyde fixation itself results in extensive cross-linking of proteins (and presumably functional groups), thus potentially resulting in the contiguous solid-phase observed. Characterizations of Gigacap Q-650M and HALOTM were also done by using Focus Ion Beam (FIB). HALOTM particle structure composed of core and the shell part was investigated and 2-D images of HALOTM were used to construct 3-D topography of it by using FIB whereas FIB images of Gigacap Q-650M could not be used to form 3-D structure because of the low resolution of images.
Citation Formats
Ö. H. Yalçın, “High resolution imaging and image analysis in porous media,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Chemical Engineering., Middle East Technical University, 2019.