Transient concentration extremum and conservatively perturbed equilibrium

In the recently introduced concept of Conservatively Perturbed Equilibrium (CPE), a chemical system is instantaneously perturbed from equilibrium while keeping the temperature and the total amount of every element constant. The concentrations of the system's species are then monitored until equilibrium is recovered. If the concentration of a given species was not initially modified by the perturbation, it will change from the initial equilibrium value over a transient evolution back to that equilibrium value. Such an unperturbed species must therefore reach at least one unavoidable extreme concentration value, a maximum or a minimum. For reversible first-order reactions, theoretical and computational procedures are presented in this paper for optimizing the maximal concentration during the transition. The main result is that this reduces the n - dimensional optimization problem of choosing the optimal initial condition and optimal stopping time to n -1 one-dimensional problems. The developed approach is illustrated by a 4-step cyclic reaction. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The concept of Conservatively Perturbed Equilibrium involves perturbing a chemical system from its equilibrium state while maintaining temperature and total amount of elements constant. The unperturbed species in the system will reach at least one extreme concentration value during the transient evolution. The optimization of maximal concentration during transition is presented for reversible first-order reactions, simplifying the overall optimization problem.