Langmuir–Hinshelwood kinetics: a singular value decomposition perspective on the quasi-steady state assumption

Abstract The Langmuir–Hinshelwood (LH) equation was derived from separation of time scales and singular perturbation arguments based on singular value decomposition analysis. The quasi-steady state assumption (QSSA) commonly considered for the traditional LH equation was mathematically justified in terms of a sufficient separation of time scales, rather than relying on specific reaction steps. The analysis was extended to second order reaction rate on the active surface, and to open reacting systems. The mathematical analysis provided back up for the broad applicability of the QSSA for LH kinetics in practical cases. Some implications for the analysis of experimental data with LH kinetics were discussed. The need to verify the compliance with the QSSA was highlighted.