Article Metrics


Online attention

4D in-situ microscopy of aerosol filtration in a wall flow filter

DOI: 10.3390/ma13245676 DOI Help

Authors: Matthew P. Jones (University of Manchester; University of Manchester at Harwell; UK Catalysis Hub, Research Complex at Harwell) , Malte Storm (Diamond Light Source) , Andrew P. E. York (Johnson Matthey Technology Centre) , Timothy I. Hyde (Johnson Matthey Technology Centre) , Gareth Hatton (Johnson Matthey Technology Centre) , Alex G. Greenaway (University of Manchester at Harwell) , Sarah J. Haigh (University of Manchester) , David S. Eastwood (University of Manchester at Harwell; University of Manchester)
Co-authored by industrial partner: Yes

Type: Journal Paper
Journal: Materials , VOL 13

State: Published (Approved)
Published: December 2020
Diamond Proposal Number(s): 23490

Open Access Open Access

Abstract: The transient nature of the internal pore structure of particulate wall flow filters, caused by the continuous deposition of particulate matter, makes studying their flow and filtration characteristics challenging. In this article we present a new methodology and first experimental demonstration of time resolved in-situ synchrotron micro X-ray computed tomography (micro-CT) to study aerosol filtration. We directly imaged in 4D (3D plus time) pore scale deposits of TiO2 nanoparticles (nominal mean primary diameter of 25 nm) with a pixel resolution of 1.6 μ m. We obtained 3D tomograms at a rate of ∼1 per minute. The combined spatial and temporal resolution allows us to observe pore blocking and filling phenomena as they occur in the filter’s pore space. We quantified the reduction in filter porosity over time, from an initial porosity of 0.60 to a final porosity of 0.56 after 20 min. Furthermore, the penetration depth of particulate deposits and filtration rate was quantified. This novel image-based method offers valuable and statistically relevant insights into how the pore structure and function evolves during particulate filtration. Our data set will allow validation of simulations of automotive wall flow filters. Evolutions of this experimental design have potential for the study of a wide range of dry aerosol filters and could be directly applied to catalysed automotive wall flow filters.

Journal Keywords: X-ray micro-CT; synchrotron imaging; novel methods; in-situ; aerosol; filtration; porous media; particulate filter; particulate matter

Subject Areas: Materials

Instruments: I13-2-Diamond Manchester Imaging