Abstract: The invention relates to a continuous process for the preparation of a high-purity hydrogenated ose by catalytic hydrogenation of the corresponding ose in falling film reactors, wherein the hydrogenation is carried out in a series of fixed beds of ruthenium catalyst comprising: a) a first hydrogenation zone consisting of at least one fixed bed of ruthenium catalyst, and b) a second hydrogenation zone consisting of at least one fixed bed of ruthenium catalyst containing a promoter.

Abstract: The present invention provides a silica-supported 12-molybdosilicic acid catalyst comprising a silica carrier and at least 10% by weight, based on the silica amount, of 12-molybdosilicic acid supported on the carrier and a method of producing formaldehyde directly from a mixed gas of methane and oxygen in the presence of the particular catalyst. Formaldehyde can be produced at a high yield in the present invention without requiring a reforming process of methane with water vapor that consumes a large amount of energy. In addition, attentions are also paid to the air pollution and water contamination problems in the present invention.