Membranes enhance catalytic processes by providing selective permeability, which allows for the precise control of reactant and product flow. This can lead to increased conversion rates and higher selectivity towards desired products. Membranes can also help in the removal of by-products or inhibitors, preventing them from interfering with the catalytic reaction. Additionally, membranes can be integrated into reactors to create membrane reactors, where the reaction and separation processes occur simultaneously, thus improving process efficiency.