A Pa/ceramic composite membrane of high H selectivity and permeability was prepared by electroless plating and used in a reactor to catalyze dehydrogenation of MeOH to manufacture HCHO. Compared with the reaction in a convenient reactor, the conversion of MeOH and the yield of HCHO increased at 623-773 K due to selective removal of H from the reaction system. At low feed rate, the conversion of MeOH was limited by thermodn. equilibrium, and the HCHO yield increased by ?0%; at intermediate feed rate, the MeOH conversion was limited by the reaction rate, and the HCHO yield increased by 10-15%.

Key words: CATALYSIS, METHANOL, REACTORS, FORMALDEHYDE, DEHYDROGENATION, CERAMICS, PALLADIUM, CHEMICAL PLATING, LAMINATED FILMS