Thermography catalyst library

Array microreactors and mass spectrometry were used to find the best composition of Pt-Pd-Ir for the dehydrogenation of cyclohexane to benzene.210,211 A catalyst library of 37 binary alloys composed of transition metals, Cu, Zn, and Ti or Si, was screened by IR thermography in the hydrogenation of 1-hexyne, and the oxidation of isooctane and toluene.212... 

Another approach that allows parallel screening to be conducted using IR thermography has been investigated as an alternate to the use of mass spectroscopy [33-35]. This meftod monitors the heat changes that occur as a result of the heat of reaction on the catalyst library surfaces. One of the claimed advantages of this method is that the activity of the catalyst library is monitored as a function of time-on-stream in parallel. However, no information on reactant conversion or product selectivity is obtained so that ranking is based upon... 

IR-thermography and combinatorial library design (doping and composition spread) lead in a few generations to new, noble-metal-free catalysts for the low-temperature oxidation of CO in air. Activity patterns could be derived from the emissivity-corrected IR thermographic image of a catalyst library. 

Holzwarth, A. and Maier, W.F. (2000) Catalytic phenomena in combinatorial libraries of heterogeneous catalysts detection of activation and deactivation by emissivity-corrected IR thermography. Platinum Met. Rev., 44, 16. 

Taylor and Morken extended the use of IR-thermography to the monitoring of the change in the heat of reaction on and in the surroundings of a bead carrying an active catalyst (Figure 5.4.4) [13]. In a search for acylation catalysts an encoded library of 3150 different potential nucleophilic catalysts was prepared by the split-and-mix procedure and tested for their acylation properties. The library beads were spread in a reaction solution of chloroform-ethanol-triethylamine-acetic anhydride, 40 6 6 3, and monitored with an IR camera. Whereas no detectable thermal... 

Figure 9.47 On-bead IR thermography screening of the SP peptidomimetic encoded library of catalysts L34 tested in the acylation of ethanol with acetic anhydride.

Holzwarth, A. Schmidt, H.-W. Maier, W., Detection of catalytic activity in combinatorial libraries of heterogeneous catalysts by IR thermography, Angew. Chem. Int. Ed. 1998,37, 2644—2647... 

Infrared thermography is a very attractive method for the detection of catalytic activity 15). As it is an optical inspection , it can be applied to all kinds of libraries and screening reactions. The detection of catalytic activity is based on reaction enthalpy (negative or positive) 16). As most oxidation reactions are significantly exothermic, IR thermography lends itself very well as a sensitive tool for the discovery of oxidation catalysts (see Section II. C) 17). 

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