TAP experimental results

Excellent summary lists of publications where the TAP technique is applied to different catalytic systems can be found in [79, 80]. These lists include the many types of catalytic materials that are studied including supported metals, mixed metal oxides, zeolites, metal particles, metals deposited on screens, catalytic monoliths, and nanoparticles or atoms deposited on microparticles, single crystals, and other model catalysts. 

With the TAP reactor system, a slide valve at the reactor exit allows a catalyst sample to be rapidly cycled between vacuum and high pressure without exposing it to the atmosphere. In the high-pressure position, the reactor effluent flows through the slide valve and an external vent where it can be analyzed 

Atmospheric flow experiments are performed after closing the slide valve. The particle bed is first exposed to a hydrogen flow (20 cc/min diluted in Ar, H2/A1 = 1) at 350 C for 1 h. More details can be found in Zheng et al. [86]. The temperature dependence of CO2 production is obtained by heating or cooling the reactor at a constant rate while maintaining an input flow of 

50 cc/min. A small amount of the reactor efQuent is diverted into the mass spectrometer chamber, and its mass spectrum is continuously monitored. 

Taking the conversion of CO or CO2 yield at the turning point from vacuum pulse response and atmospheric flow data, the apparent kinetic rate constant can be calculated. In combination with the gas residence time (t) in the catalyst zone, the apparent kinetic rate constant is given by the following expression  

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