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Off-site regeneration of hydrotreatment catalysts
391 have shown (Harwell Report MPD/NBS/189) that analysis of the line broadening can be used to distinguish the effects of crystallite size, strain and paracrystallinity and have demonstrated that the catalyst exhibits paracrystal1inity;i.e. structural perturbation of the nickel crvstallites. Similar effects have been found by Hosemann and his coworkers (Bet+. Buns., 70 (1966), 796 and 7th Int. Congr. Catal., Tokyo, 1980) for iron-alumina ammonia-synthesis catalysts and coprecipitated copper-zinc-alumina low-pressure methanol-synthesis catalysts. The results are interpreted as indicating that a spine1 phase (NiA1204 in the case of the nickel catalyst) is likely to be present in the crystallites of the metallic component.
Off-Site Regeneration Catalysts
of Hydrotreatment
In a previous issue of Applied Catalysis (Vol. 1, No.5) the facilities for catalyst regeneration operated by Catalyst Recovery International, S.A., of Rodange, Luxemburg, were described. Dr. Georges Berrebi, of Eurecat S.A., La Voulte-sur-Rhone, France, has now provided details of the operations of his organisation. Whereas it used to be common practice for catalysts contaminated by the carbonaceous deposits formed on their surfaces during normal use to be regenerated on-site, operators now prefer to have regeneration performed elsewhere in specialist facilities. In this way, by using a spare charge of catalyst, they avoid environmental pollution (by sulphur compounds), expensive plant down-time and loss of Droduction. In the Eurecat facility. which can treat hydrodesulphurisatibn, reforming and hydrogenation catalysts as well as zeolites, the regeneration is carried out in a continuous rotolouvre which is a sophisticated cylindrical drum arranged to rotate slowly on a horizontal axis and enclosing a series of overlapping radial louvres. The louvres extend the full length of the drum (11 m) to form a conical inner shell which increases in diameter towards the discharge end (2-2.5 m). The catalyst passes from one end of the drum to the other through a series of channels. Hot air produced in an
external and independent combustion chamber passes through the spaces between the louvres and permeates the thin layer of catalyst. The hot gases leaving the catalyst (containing SO2 and C02) pass through a heat exchanger where the fresh air is heated. The geometry of the bed is such that no hot-spots are formed during the regeneration process; the temperatures are monitored and controlled automatically. After treatment, the catalysts recover entirely their mechanical strength and their textural and structural characteristics and may have activities of above 95% of the original activities. The treatment uses two temperature steps, the first at low temperatures (typically 280°C) to remove S and the second at higher temperatures (typically 500°C) to remove carbon. Dr. Berrebi's document provides details of the success achieved in regenerating four typical CO-MO or Ni-Mo catalysts; in one case, a successful regeneration was achieved after an unsuccessful onsite regeneration procedure had been attempted. Further details of these results and of the plant can be obtained from Dr. Berrebi.
GRECO Charbon The French group, GRECO Charbon, held its first open meeting in Lyon on Among the seven presentations May 27th. given, two were concerned specifically with catalytic topics. The first was "Catalysis in the Hydroliquefaction of Coal" by H. Charcosset of the Institut de Recherches sur la Catalyse, CNRS, Lyon; this concerned mainly iron-based nsturally occurring or synthetic The second was "Catalytic catalvsts. Hydrogenolysis of Model Compounds-of Coal-Derived Naphthas to SNG," given by G. Leclercq of the Laboratoire de Catalyse, CNRS, Lille. The GRECO Charbon group is currently extending its activities, mainly in the field of coal characterisation.
Stop-press The first circular has just been issued for the 8th International Congress on Catalysis, to be held in the Congress Centre (ICC), West Berlin, from 2-6 July 1984. Special emphasis will be paid to the following topics:
Off-Site Regeneration Catalysts
of Hydrotreatment
In a previous issue of Applied Catalysis (Vol. 1, No.5) the facilities for catalyst regeneration operated by Catalyst Recovery International, S.A., of Rodange, Luxemburg, were described. Dr. Georges Berrebi, of Eurecat S.A., La Voulte-sur-Rhone, France, has now provided details of the operations of his organisation. Whereas it used to be common practice for catalysts contaminated by the carbonaceous deposits formed on their surfaces during normal use to be regenerated on-site, operators now prefer to have regeneration performed elsewhere in specialist facilities. In this way, by using a spare charge of catalyst, they avoid environmental pollution (by sulphur compounds), expensive plant down-time and loss of Droduction. In the Eurecat facility. which can treat hydrodesulphurisatibn, reforming and hydrogenation catalysts as well as zeolites, the regeneration is carried out in a continuous rotolouvre which is a sophisticated cylindrical drum arranged to rotate slowly on a horizontal axis and enclosing a series of overlapping radial louvres. The louvres extend the full length of the drum (11 m) to form a conical inner shell which increases in diameter towards the discharge end (2-2.5 m). The catalyst passes from one end of the drum to the other through a series of channels. Hot air produced in an
external and independent combustion chamber passes through the spaces between the louvres and permeates the thin layer of catalyst. The hot gases leaving the catalyst (containing SO2 and C02) pass through a heat exchanger where the fresh air is heated. The geometry of the bed is such that no hot-spots are formed during the regeneration process; the temperatures are monitored and controlled automatically. After treatment, the catalysts recover entirely their mechanical strength and their textural and structural characteristics and may have activities of above 95% of the original activities. The treatment uses two temperature steps, the first at low temperatures (typically 280°C) to remove S and the second at higher temperatures (typically 500°C) to remove carbon. Dr. Berrebi's document provides details of the success achieved in regenerating four typical CO-MO or Ni-Mo catalysts; in one case, a successful regeneration was achieved after an unsuccessful onsite regeneration procedure had been attempted. Further details of these results and of the plant can be obtained from Dr. Berrebi.
GRECO Charbon The French group, GRECO Charbon, held its first open meeting in Lyon on Among the seven presentations May 27th. given, two were concerned specifically with catalytic topics. The first was "Catalysis in the Hydroliquefaction of Coal" by H. Charcosset of the Institut de Recherches sur la Catalyse, CNRS, Lyon; this concerned mainly iron-based nsturally occurring or synthetic The second was "Catalytic catalvsts. Hydrogenolysis of Model Compounds-of Coal-Derived Naphthas to SNG," given by G. Leclercq of the Laboratoire de Catalyse, CNRS, Lille. The GRECO Charbon group is currently extending its activities, mainly in the field of coal characterisation.
Stop-press The first circular has just been issued for the 8th International Congress on Catalysis, to be held in the Congress Centre (ICC), West Berlin, from 2-6 July 1984. Special emphasis will be paid to the following topics: