Abstract: The present invention relates to a catalyst system which is a mixture of at least two catalytic species, the first catalytic species being a dehydrogenation catalyst and the second catalytic species being an epoxidation catalyst and comprising silver. The present invention also relates to a process for the production of epoxides, in particular a process for the production of an epoxide from an alkane or a mixture comprising an alkane and an alkene, which process comprises contacting said alkane or mixture comprising said alkane and said alkene and a source of oxygen with such a catalyst system comprising a mixture of at least two catalytic species, the first catalytic species providing dehydrogenation activity and the second catalytic species providing epoxidation activity and comprising silver.

Abstract: The present invention relates to a process for preparing an ethanolamine having an improved colour quality. The process comprises contacting ethanolamine with an activated carbon free of one or more metals chosen from Re, Ru, Rh, Pd, Os, Ir, Pt and Ag. The contacting can be carried out at a temperature of from 10 to 200° C., and during a period sufficient to reduce the colour of the ethanolamine, in particular a period such that the colour index (as measured according to the ASTM standard D 1209) of the ethanolamine becomes equal to or less than 50 or 40 Pt/Co. The contacting can be carried out during or after the stage of preparation of the ethanolamine, preferably during or after the stage of purification of the ethanolamine.

Abstract: The present invention relates to a process for manufacturing ethylene oxide by the catalytic oxidation reaction of ethylene by molecular oxygen in a tube reactor. The reactor comprises a bundle of reaction tubes (5) which are immersed in a heat exchange fluid and filled with a solid silver-based catalyst (8) and which are traversed by a reactive gas current containing ethylene and molecular oxygen, which in contact with the catalyst forms the ethylene oxide. The area of the internal cross-section of the reaction tubes (5) decreases between the inlet (1) and the outlet (3) of the tubes over at least a portion of the length of the tubes and remains constant over any remaining portion. The process makes it possible to increase the selectivity of the reaction to ethylene oxide for a given production of ethylene oxide.

Abstract: The invention concerns a method for purifying flue gases before they are released into the atmosphere of their nitrogen oxides N2O and NOx by reaction with ammonia by causing them to circulate at temperatures between 200 and 600° C. on a catalyst based on beta-zeolite loaded with iron. The invention is particularly useful for treating tail gases from factories producing nitric acid.

Abstract: The invention concerns a method for purifying flue gases before they are released into the atmosphere of their nitrogen oxides N2O and NOx by reaction with ammonia by causing them to circulate at temperatures between 200 and 600° C. on a catalyst based on beta-zeolite loaded with iron. The invention is particularly useful for treating tail gases from factories producing nitric acid.