What are membrane reactors and what are their advantages?

Membrane reactors combine reaction and separation in one unit. Types: catalytic membrane (membrane is catalyst), packed bed with membrane wall (selective product removal), and membrane with external catalyst. Advantages: shift equilibrium-limited reactions by removing product (e.g., H2 removal in dehydrogenation), improve selectivity by controlled reactant addition, reduce downstream separation, and intensify process. Challenges: membrane stability at reaction conditions, cost, sealing, and scale-up. Applications: hydrogen production, dehydrogenation, and partial oxidation.