Graded metal catalytic tubes

摘要

An improved metal catalytic tube includes an elongated metal member formed at least partially of metal particles and including a catalytic enhancement incorporated into the metal member. The metal member is formed with a cavity and includes an inner surface defined by the cavity and an outer surface opposite the inner surface. The metal member has a porosity at the outer surface that is greater than the porosity at the inner surface. The porosity at the inner surface is sufficiently low that the metal member can carry a quantity of gas through the cavity without the gas leaking through the inner surface of the metal member. The abstract shall not be used for interpreting the scope of the claims.