Temporal Analysis of Products (TAP), (TAP-2), (TAP-3) is an experimental technique for studying the kinetics of physico-chemical interactions between gases and complex solid materials, primarily heterogeneous catalysts.
Since its invention by Dr. John T. Gleaves (then at Monsanto Company) in late 1980s,[1] TAP has been used to study a variety of industrially and academically relevant catalytic reactions, bridging the gap between surface science experiments and applied catalysis.
In a typical TAP pulse-response experiment, very small (~10−9 mol) and narrow (~100 μs) gas pulses are introduced into the evacuated (~10−6 torr) microreactor containing a catalytic sample.
Unconverted and newly formed gas molecules eventually reach the reactor's outlet and escape into an adjacent vacuum chamber, where they are detected with millisecond time resolution by the QMS.
The exit-flow rates of reactants, products and inert molecules recorded by the QMS are then used to quantify catalytic properties and deduce reaction mechanisms.