Fast reaction limits for a nonmonotone reaction–diffusion system with reversible reaction

Abstract We study the fast reaction limit for a two-component reaction–diffusion system with equal diffusion and a reversible reaction whose reaction structure is allowed to be nonmonotone. Under a structural condition on the reaction limit set, we prove that the sum of the two components converges to the solution of a reduced scalar equation. We also show that, for every positive time, the solution is driven to the reaction limit set.