tailieunhanh - Applied Catalysis A: General 180 (1999)

Abstract A new method is presented for improving the performance of red mud as a hydrogenation catalyst (a residue from the production of alumina by the Bayer process that contains iron oxides), based on the method developed by . Pratt and V. Christoverson, Fuel 61 (1982) 460. The activation method consists essentially in dissolving red mud in a mixture of aqueous hydrochloric and phosphoric acids, boiling the resulting solution, adding aqueous ammonia until pH 8, and ®ltering, washing, drying and calcining the resulting precipitate. . | APPLIED I CATALYSIS ELSEVIER A GENERAL Applied Catalysis A General 180 1999 399-409 A new method for enhancing the performance of red mud as a hydrogenation catalyst Jorge Alvarez Salvador Ordonez Roberto Rosal Herminio Sastre Fernando V. Diez Department of Chemical and Environmental Engineering University of Oviedo 33071-Oviedo Spain Received 22 April 1998 received in revised form 30 October 1998 accepted 5 November 1998 Abstract A new method is presented for improving the performance of red mud as a hydrogenation catalyst a residue from the production of alumina by the Bayer process that contains iron oxides based on the method developed by . Pratt and V. Christoverson Fuel 61 1982 460. The activation method consists essentially in dissolving red mud in a mixture of aqueous hydrochloric and phosphoric acids boiling the resulting solution adding aqueous ammonia until pH 8 and filtering washing drying and calcining the resulting precipitate. The catalyst thus obtained is characterised and after sulphidation tested activity and life for the hydrogenation of a light fraction of an anthracene oil. The catalytic performance is compared with that of sulphided untreated red mud and sulphided red mud activated by the method of Pratt and Christoverson. This activation method has proved to be more effective in improving the performance of red mud as a hydrogenation catalyst than the method of Pratt and Christoverson since the activated catalyst presents a slightly higher level of activity and a markedly extended active life. 1999 Elsevier Science . All rights reserved. Keywords Red mud Anthracene oil Catalyst deactivation Catalytic hydrogenation Scanning electron microscopy X-ray diffraction Phosphorus promotional effect 1. Introduction Red mud RM is a by-product in the manufacture of alumina by Bayer process that contains mainly oxides of iron aluminium titanium silicon calcium and sodium. Sulphided red mud is active as a hydrogenation catalyst due to its iron .