A new method for enhancing the performance of red mud as a hydrogenation catalyst Original Research Article

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 K.C. 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.