Improvements relating to the preparation of catalysts for the refining of lubricating oils and to the use of such catalysts in such refining

摘要

A catalyst useful for refining lubricating oils consists of Al2O3 and 4-12% of MoO3, 6-20% of Fe2O3, the content of Fe2O3 being at least equal to the content of MoO3. The catalyst may be activated by contact in the presence of hydrogen with a sulphur-containing mineral oil at a temperature of at least 300 DEG C. for a period of at least 24 hours. The Al2O3 used in making the catalyst is preferably g -Al2O3 obtained by calcination of hydrargillite at above 500 DEG C. Suitably the Al2O3 used has pores of approximately 30 and surface area of 250 sq. m./gm. Preferably the Al2O3 is impregnated with a solution of ferric nitrate which has been acidified with nitric acid and thereafter dried at 110 DEG C., calcined at 550 DEG C., impregnated with ammonium molybdate solution and further dried and calcined. Lubricating oils are contacted in the presence of hydrogen at 150 DEG -340 DEG C. with catalysts as described above. Preferably the hydrogen pressure is 5-70 atmospheres and the hydrogen feed rate is 5-150 volumes per volume of oil treated. An example is given.