Transient distributions of composition and temperature in a gas–solid packed bed reactor by near-infrared tomography

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 189-190; pp. 383 - 392
• Main Authors: tSaoir, Méabh Nic An, Fernandes, Daniel Luis Abreu, McMaster, Michael, Kitagawa, Kuniyuki, Hardacre, Christopher, Aiouache, Farid
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.05.2012; Elsevier
• Subjects: Applied sciences; benzene; Chemical engineering; Composition effects; Deuteration; Dynamics; Exact sciences and technology; hydrogen; hydrophobicity; Isotopic exchange; Near-infrared tomography; Packed bed; platinum; porosity; Porous media; Reactors; styrene; temperature; Three dimensional; Tomography; Transport processes; Vapour; Visualization; Walls; water vapor; Porous media; Visualization; Packed bed; Transport processes; Isotopic exchange; Near-infrared tomography; Cartography; Porous medium; Fixed bed reactor; Exchange reaction; Aspect ratio; Convection; Transport process; Non isothermal condition; Tomography; Gas solid; Porosity; Wall effect
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2012.02.037

[Display omitted] ► 3D profiles of vapours and temperature in packed reactors by NIR diffuse tomography. ► The design includes a tunable diode laser, array detector and Pt-resin packing. ► Porosity driven-dynamic lags between water and deuterated water were observed. ► Deviation in H2O composition of 16.1% between mass-spectrometry and tomography data. ► Deviation of 18.3% in temperature between thermocouple and tomography data. Near-infrared diffuse tomography was used in order to observe dynamic behaviour of flowing gases by measuring the 3D distributions of composition and temperature in a weakly scattering packed bed reactor, subject to wall effects and non-isothermal conditions. The technique was applied to the vapour phase hydrogen isotopic exchange reaction in a hydrophobic packing of low aspect ratio made of platinum on styrene divinyl benzene sulphonate copolymer resin. The results of tomography revealed uneven temperature and composition maps of water and deuterated water vapours in the core-packed bed and in the vicinity of the wall owing to flow maldistribution. The dynamic lag between the near-wall water vapour and deuterated water vapour compositions were observed suggesting that the convective transfer which was significant near the wall at the start, owing to high porosity, was also effective at large conversions.