| 摘要 |
1,126,858. Polymerisation catalysts. STANDARD OIL CO. 16 Feb., 1967 [16 Feb., 1966], No. 7439/67. Addition to 1,045,178. Heading B1E. [Also in Division C3] The catalyst of the parent Specification No. 1,045,178 which comprises (a) a minor amount of an oxide of Mo in a sub-maximum valency state supported on (b) a high surface area (1-1500 m<SP>2</SP>/gm) Al 2 O 3 which has been hydrohalogenated at 150-500‹C and (c) one or more of sodium, lithium or calcium as promoters is modified in that the hydrohalogenation is effected in two stages-(1) at 200 up to 400‹C for “-5 hours and (2) above 400- 550‹C for “-5 hours. |
