Multiplicity results and closed-form solution for catalytic reaction in a flat particle

•The strongly nonlinear mathematical model describing catalytic reaction in a flat particle has been revisited.•The original boundary value problem is exactly solvable and obtained the exact in the implicit form.•The problem may admit unique, dual or even more triple solutions depending on the value of Thiele modulus.

Assume a flat geometry for the particle and that conductive heat transfer is negligible compared to convective heat transfer in the study of heat and mass transfer for a catalytic reaction within a porous catalyst flat particle. This article shows the governing differential equation, which is the direct result of a material and energy balance, is exactly solvable and furthermore, gives exact analytical solution in the implicit form for further physical interpretation. A full discussion is given and, it is also revealed that the problem may admit unique, dual or even more triple solutions depending on the values of Thiele modulus and other parameters of the model.