Claims
- 1. A silica/magnesia cogel solid containing from about 5% to about 50% by weight of magnesia, based on the total of silica and magnesia, said silica/magnesia having a porosity of less than 0.2 cc/g, and essentially all of the magnesia being chemically incorporated within the cogel such that no free magnesia, detectable as magnesium hydroxide by IR spectroscopy, is present in the cogel.
- 2. A silica-magnesia cogel solid according to claim 1 having a porosity of less than 0.2 cc/g and a sodium content below 0.4% by weight.
- 3. A petroleum cracking catalyst comprising:
- 40 to 90% by weight of silica/magnesia catalyst base of claim 2,
- 5 to 40% by weight of zeolite,
- 0 to 40% by weight of alumina,
- 0 to 50% by weight of clay, and
- 0 to 50% by weight of binder.
- 4. A process for preparing a catalyst, wherein a silica/magnesia catalyst cogel is first prepared according to the following steps:
- (i) intimately mixing a liquid magnesia source at a pH below 10 and liquid silica source in proportions providing a magnesia content in the range 5% to 50% by weight based on the total of silica and magnesia in a liquor with a pH from 9.0 to 10, and
- (ii) maintaining the resultant liquor at a pH 9.0 to 10 until no free magnesia is detected in the solid phase by IR spectroscopy, and magnesium ions are not detected in the liquid phase, thereby obtaining a said silica/magnesia catalyst cogel in which essentially all of the magnesia is chemically incorporated within the cogel, and the thus prepared cogel is then intimately mixed with a zeolite and, optionally, alumina and, optionally, a clay and the resultant mixture dried to provide a petroleum cracking catalyst with the composition
- 40 to 90% by weight silica/magnesia base,
- 5 to 40% by weight zeolite,
- 0 to 40% by weight alumina, and
- 0 to 50% by weight clay.
Priority Claims (1)
Number |
Date |
Country |
Kind |
8619151 |
Aug 1986 |
GBX |
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Parent Case Info
This is a continuation of application Ser. No. 07/079,082, filed July 29, 1987 (U.S. Pat. No. 4,849,394).
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
2947708 |
Wilson, Jr. |
Aug 1960 |
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4280898 |
Tatterson et al. |
Jul 1981 |
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Foreign Referenced Citations (2)
Number |
Date |
Country |
245079 |
Feb 1963 |
AUX |
561745 |
Aug 1958 |
CAX |
Continuations (1)
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Number |
Date |
Country |
Parent |
79082 |
Jul 1987 |
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