Recent advances in dynamic chemical characterization using Temporal Analysis of Products

Publication date: September 2018Source: Current Opinion in Chemical Engineering, Volume 21Author(s): Rebecca Fushimi, John GleavesThe Temporal Analysis of Products (TAP) technique is a pulse response methodology that reveals the time-dependent evolution of chemical processes between a gas phase molecule and a solid surface. By simplifying both the transport and kinetic processes the complexity of a multistep chemical processes can be distilled to where the underlying fundamental steps can be distinguished. Moreover, the technique is applicable to real materials (e.g. industrial catalysts) and hence the complexity of the solid is studied intact; a ‘top-down’ approach. In this short review we discuss key theoretical advancements in the interpretation of pulse response data; though not yet widely implemented, we will highlight the broader impacts of the Y-Procedure method [1••], momentary equilibrium phenomena [2••] and kinetic coherency discrimination [3••] over more commonly used analysis techniques. The conventional TAP approach for mechanism development is well-laid out in a recent work focused on the upgrading of ethanol to higher hydrocarbons. This includes detailed comparison of the time characteristics of reactant, intermediate and product pulses in both single pulse and pump/probe modes [4••]. This work calls to mind some of the challenges in the conventionally used residual gas analyzer for pulse response detection of homologous products. A new dete...

Source: Current Opinion in Chemical Engineering - July 11, 2018 Category: Chemistry Source Type: research