Abstract: Catalysts for ammonia synthesis based on ruthenium, directly supported over graphite having BET specific surface area in excess of 10 m2/g, preferably in excess of 100 m2/g and more preferably in excess of 280 m2/g, the graphite being characterised by X-ray diffraction pattern containing the diffraction lines characteristic of the crystalline graphite only, with exclusion of relevant bands due to amorphous carbon, to which catalysts barium, caesium and potassium are added as promoters. The graphitic supports allow to avoid the known pre-treatments and post-treatments needed in the case of supports obtained by partial graphitisation of active carbons and during use they are affected negligibly by the methanation shown by the supports obtained from active carbons. Furthermore, the catalysts of the present invention are characterised by a very high activity, even with ruthenium loadings well below the known loading.

Abstract: The present invention relates to a catalyst for the dehydrogenation of ethylbenzene to styrene and to a process for the preparation thereof. The catalyst contains iron oxide, potassium oxide and calcium oxide, preferably also cerium oxide and molybdenum oxide, and is characterised by a magnesium content (expressed as MegO) lower than 0.001 %.

Abstract: Catalysts for ammonia synthesis based on ruthenium, directly supported over graphite having BET specific surface area in excess of 10 m2/g, preferably in excess of 100 m2/g and more preferably in excess of 280 m2/g, the graphite being characterised by X-ray diffraction pattern containing the diffraction lines characteristic of the crystalline graphite only, with exclusion of relevant bands due to amorphous carbon, to which catalysts barium, caesium and potassium are added as promoters. The graphitic supports allow to avoid the known pre-treatments and post-treatments needed in the case of supports obtained by partial graphitisation of active carbons and during use they are affected negligibly by the methanation shown by the supports obtained from active carbons. Furthermore, the catalysts of the present invention are characterised by a very high activity, even with ruthenium loadings well below the known loading.

Abstract: A process for producing the precursor of a precipitated catalyst for the sub.3 synthesis, based on Fe, Al, Co and K oxides, which comprises the steps of:(A) preparing an aqueous solution of water-soluble compounds of Fe, Al and Co--adding iron as a water-soluble ferrous salt of an organic acid--and causing, by addition of an alkaline precipitating solution, the co-precipitation of the corresponding (Fe, Al and Co) hydroxides, which still contain iron in the ferrous form;(B) oxidizing the hydroxide suspension prepared according to point (A) until divalent iron and trivalent iron are in a ratio to each other which ranges from 0.20 to 0.50;(C) operating an alkaline doping with a potassium compound and heating in an inert atmosphere up to above 850.degree. C.

Abstract: A process for preparing iron-based catalysts for the synthesis of ammonia by melting of magnetite along with metal oxides as promoters, subsequent cooling of the molten mass and reduction thereof to the desired size, wherein the abovesaid cooling occurs at a rate higher than 25.degree. C./min., preferably ranging from 100.degree. C. to 1600.degree. C./min., at a temperature ranging from 1700.degree. C. to 700.degree. C.The present invention relates to a process for preparing iron-based catalysts having a high activity in the ammonia synthesis, and to the catalyst so obtained.

Abstract: A method for the preparation of catalysts, particularly suitable for the hydrogenation of organic compounds, according to which method a catalytic element, preferably selected from the VIII Group elements, is supported on the outer surface of an adsorbent carbon, said method being characterized by the fact that:(a) said carbon containing an amount of ash lower than 1% by weight, is suspended in water;(b) a liquid immiscible with water is added to the suspension obtained according to (a), the volume of said immiscible liquid being substantially equal to or lower than the volume of the carrier's pores;(c) an aqueous solution, containing a compound of the catalytic element, is brought into contact with the suspension obtained according to (b).