title: An in situ spatially resolved analytical technique to simultaneously probe gas phase reactions and temperature within the packed bed of a plug flow reactor.
abstract: This paper reports the detailed description and validation of a fully automated, computer controlled analytical method to spatially probe the gas composition and thermal characteristics in packed bed systems. As an exemplar, we have examined a heterogeneously catalysed gas phase reaction within the bed of a powdered oxide supported metal catalyst. The design of the gas sampling and the temperature recording systems are disclosed. A stationary capillary with holes drilled in its wall and a moveable reactor coupled with a mass spectrometer are used to enable sampling and analysis. This method has been designed to limit the invasiveness of the probe on the reactor by using the smallest combination of thermocouple and capillary which can be employed practically. An 80 μm (O.D.) thermocouple has been inserted in a 250 μm (O.D.) capillary. The thermocouple is aligned with the sampling holes to enable both the gas composition and temperature profiles to be simultaneously measured at equivalent spatially resolved positions. This analysis technique has been validated by studying CO oxidation over a 1% Pt/Al2O3 catalyst and the spatial resolution profiles of chemical species concentrations and temperature as a function of the axial position within the catalyst bed are reported.
authors.affiliation: CenTACat, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast, BT9 5AG, Northern Ireland, UK.
authors.forename: Jamal
authors.initials: J
authors.lastname: Touitou
authors.forename: Robbie
authors.initials: R
authors.lastname: Burch
authors.forename: Christopher
authors.initials: C
authors.lastname: Hardacre
authors.forename: Colin
authors.initials: C
authors.lastname: McManus
authors.forename: Kevin
authors.initials: K
authors.lastname: Morgan
authors.forename: Jacinto
authors.initials: J
authors.lastname: Sá
authors.forename: Alexandre
authors.initials: A
authors.lastname: Goguet
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry; D002245:Carbon Dioxide / Q000138:chemical synthesis* / Q000737:chemistry; D002248:Carbon Monoxide / Q000737:chemistry*; D002384:Catalysis; D013058:Mass Spectrometry / Q000295:instrumentation; D010984:Platinum / Q000737:chemistry; D013696:Temperature
chemical_list: D002245:Carbon Dioxide; D010984:Platinum; D002248:Carbon Monoxide; D000537:Aluminum Oxide