View in EDS

Particle size influence on the pore development of nanopores in coal gasification chars: From micron to millimeter particles.

Saved in:
Bibliographic Details
Title: Particle size influence on the pore development of nanopores in coal gasification chars: From micron to millimeter particles.
Authors: Coetzee, G. Hennie1, Sakurovs, Richard2, Neomagus, Hein W.J.P.1 hein.neomagus@nwu.ac.za, Everson, Raymond C.1, Mathews, Jonathan P.1,3, Bunt, John R.1
Source: Carbon. Feb2017, Vol. 112, p37-46. 10p.
Subjects: Coal gasification, Nanopores, Particle size distribution, Mass transfer, Small-angle X-ray scattering, South Africans
Abstract: The influence of particle size on the growth of nanopores arising from gasification of a South African coal-char was investigated using small angle X-ray scattering. Three different char sizes (75 μm, 2 and 20 mm) were gasified between 800 and 1000 °C to specific conversions up to 50% and the pore development during CO 2 and steam gasification was compared. For the CO 2 gasified chars studied here, particle size influenced the rates of individual pore growth for all pore sizes and an increased development of micro-, and macropores was observed as particle size increased. For the steam gasified chars studied here, particle size only influenced the rates of individual pore growth for larger pores, with prevalence of macropore development. A novel application of monitoring pore development as a function of distance from the surface was applied to the 20 mm gasified char, spanning the surface to the interior of the spherical particle. The portion closest to the surface, showed the greatest pore development over the entire pore range, followed by the interior and centre. The radial changes in growth rate for individual pore sizes demonstrated intra-particle mass transfer limitations for the 20 mm particle studied here under these conditions. [ABSTRACT FROM AUTHOR]
Copyright of Carbon is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:The influence of particle size on the growth of nanopores arising from gasification of a South African coal-char was investigated using small angle X-ray scattering. Three different char sizes (75 μm, 2 and 20 mm) were gasified between 800 and 1000 °C to specific conversions up to 50% and the pore development during CO 2 and steam gasification was compared. For the CO 2 gasified chars studied here, particle size influenced the rates of individual pore growth for all pore sizes and an increased development of micro-, and macropores was observed as particle size increased. For the steam gasified chars studied here, particle size only influenced the rates of individual pore growth for larger pores, with prevalence of macropore development. A novel application of monitoring pore development as a function of distance from the surface was applied to the 20 mm gasified char, spanning the surface to the interior of the spherical particle. The portion closest to the surface, showed the greatest pore development over the entire pore range, followed by the interior and centre. The radial changes in growth rate for individual pore sizes demonstrated intra-particle mass transfer limitations for the 20 mm particle studied here under these conditions. [ABSTRACT FROM AUTHOR]
ISSN:00086223
DOI:10.1016/j.carbon.2016.10.088