GB1499570A - Production of white mineral oil - Google Patents

Abstract

1499570 Producing white mineral oil ATLANTIC RICHFIELD CO 9 April 1975 [11 April 1974] 14631/75 Heading C5E White mineral oil is produced from a mineral oil distillate of lubricating viscosity by first contacting the distillate with hydrogen in the presence of a sulphur-resistant catalyst to form a hydrogenated oil and then contacting at least a portion of the hydrogenated oil with hydrogen in the presence of a second catalyst to form a refined oil from which the white mineral oil is recovered, the second catalyst comprising a major amount of a support, a minor catalytically-effective amount of at least one palladium component and a minor amount of at least one halogen component sufficient to improve the hydrogenation activity of the second catalyst. The first contacting step may be effected at a temperature of 600‹-800‹ F., a pressure of 1500-5000 p.s.i.g., a weight hourly space velocity of 0À1-1À0 and a hydrogen to mineral oil distillate ratio of 1000-5000 s.c.f./b. and the second contacting step may be effected at a temperature of 400‹-650‹ F., a pressure of 1500-5000 p.s.i.g., a weight hourly space velocity of 0À1-1À0 and a hydrogen to hydrogenated oil ratio of 500-5000 s.c.f./b. The first catalyst may comprise a major amount of a support and a minor amount of a metallic component, e.g. tin, vanadium, chromium, molybdenum, tungsten, iron, cobalt or nickel present as free metals, oxides or sulphides, and preferably comprises 5-40% by weight of a Group VIB metal, chromium molybdenum or tungsten calculated as metal oxide and 2-15% by weight of a Group VIII metal, iron, cobalt or nickel, calculated as free metal. The support for the first and second catalysts may be calcined or otherwise activated alumina derived from hydrous alumina comprising alumina trihydrate, alumina monohydrate, amorphous hydrous alumina and mixtures thereof. The palladium component of the second catalyst may be present as the metal or sulphide or oxide, preferably in an amount of 0À01-5% by weight. The halogen component, which may be fluorine, chlorine or bromine or mixtures thereof, may be added in an amount of 0À1-4% by weight and may be added to the alumina support during preparation of the support or before or after the addition of palladium. The halogen may be added as an aqueous solution or gaseous stream of hydrogen fluoride, hydrogen chloride or hydrogen bromide, or by the use of a mixture of chloropalladic acid and hydrogen chloride. The catalysts used in the first and second stages may be hydrogen purged and/or prereduced prior to use, by heating in the presence of hydrogen at 300‹-600‹ F.