Series CAT-1 cell system The Ventacon Series CAT cell provides catalytic chemists with a facility to activate catalysts and then to study them in their F-T Raman instruments. Most chemistry on catalysts involves heating the sample (in powder or pellet form) either in vacuum or in an oxidizing or reducing atmosphere as a first stage. The reactions that take place under these conditions normally make the catalyst active. Raman studies before and after activation can be highly informative. Reactants passed over a heated specimen of the activated catalyst can then provide detailed information on the chemistry involved if one observes the in situ process and the makeup of the exhaust gas. A popular method of the in situ analysis is vibrational spectroscopy - both infrared and Raman. Fluorescence tends to cause severe problems with Raman measurements but the use of near infrared sources and F-T processing minimise this particular nuisance. The Ventacon CAT cell system comprises of a glass horizontal tube containing the catalyst held with glass wool pads inside a small oven surrounded with insulating material. Gas can be passed through the catalyst via external flexible tubes or the sample can be evacuated.
Activated catalysts are frequently coloured and hence absorb the incident laser radiation when studying the Raman spectra. It is well established that this absorption can be minimised by moving the sample beneath the laser beam continuously. The Ventacon Cat cell gently moves up and down whilst spectra are recorded hence the laser beam tracks across the catalyst surface. The Ventacon CAT cell system must be powered by one of the Ventacon D Series Universal Power supplies. These supplies provide energy for the oven and power and control the vertical translation system.
Safety Note All Ventacon accessories operate within your instrument's sample chamber with the lid closed and interlocked. Users of Nicolet Instruments must fit a model A-22 Light Trap into their instruments. This is provided f.o.c. by Ventacon Ltd. To contact us
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