In this example, we describe a model for the optimization of a typical process operation in the petrochemical industry. Our objective is to determine the optimal set of operating conditions for an alkylation process that combines olefin with isobutane, in the presence of a catalyst, to form alkylate. Many chemical processes are characterized by nonlinear equilibrium (material and energy balance) constraints. In addition, the processes are typically constrained by restrictions on the operating ranges of the decision variables such as amounts and rates of the components used, temperature, pressure, and so on. This worksheet requires that the Global Optimization Toolbox has been added to Maple.