EP0085357A2
Expired / Lapsed
EP
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Heating silica gel in inert atmosphere before activation
Assignee: Phillips Petroleum Co
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Filing: 1983-01-19
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Granted: —
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Expires: 2003-01-19
Abstract
Abstract A silica hydrogel is contacted with a hydroxy-containing organic compound which is not completely miscible with water but which is sufficiently miscible with water so as to remove water, and thereafter the organic compound is removed by heating in an inert atmosphere prior to activation by heating in air. The heating in the inert atmosphere allows utilizing preferred organic compounds such as C 5 and C 6 alcohols which are desirable from a commercial standpoint because of the easy separation for recycle. In a preferred embodiment, the hydrogel is aged at a pH of 7 to 9 by means of either adding a base or by utilizing a chromium component containing bound nitrogen.
Inventors
- 👤 Donald Reinhold Witt
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 11:33
CPC Classifications
B; B01; B01J; B01J21/00; B01J21/06; B01J21/063; B01J23/00; B01J23/16; B01J23/24; B01J23/26; B01J37/00; B01J37/0009; B01J37/0018; C; C08; C08F; C08F10/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
91 words
A process for making a polymerization catalyst, characterized by forming a silica hydrogel; aging said hydrogel for a time of at least one hour; treating the thus aged hydrogel with a volatile liquid hydroxy-containing organic compound having a solubility in water of less than 6 grams per 100 grams of water to convert said hydrogel to a xerogel; subjecting the thus formed xerogel to a heat treatment in an inert atmosphere at an elevated temperature; and activating the thus heat treated xerogel, said xerogel also containing chromium, in an oxygen-containing ambient.
Claim 2
Dependent Claim
91 words
A process for making a polymerization catalyst, characterized by forming a silica hydrogel; aging said hydrogel for a time of at least one hour; treating the thus aged hydrogel with a volatile liquid hydroxy-containing organic compound having a solubility in water of less than 6 grams per 100 grams of water to convert said hydrogel to a xerogel; subjecting the thus formed xerogel to a heat treatment in an inert atmosphere at an elevated temperature; and activating the thus heat treated xerogel, said xerogel also containing chromium, in an oxygen-containing ambient.
Claim 3
Dependent Claim
15 words
The process of claim 1 characterized in that said silica hydrogel is a silica-titania-chromium tergel.
Claim 4
Dependent Claim
36 words
The process of claim 1 or 2 characterized in that said hydroxy-containing organic compound is a C 5 or C 6 alcohol; in particula: wherein said alcohol is selected from 3-methyl-l-butanol, 1-pentanol, and 1-hexanol, and mixturesthereof.
Claim 5
Dependent Claim
46 words
The process of any of claims 1 to 3 characterized in that said inert ambient comprises nitrogen and said heat treatment in said nitrogen is carried out for a time within the range of 15 minutes-to 1 hour at a temperature within the range of 427-871°C.
Claim 6
Dependent Claim
27 words
The process of any of claims 1 to 4 characterized in that said activation is carried out in air at a temperature within the range of 649-816°C.
Claim 7
Dependent Claim
92 words
The process of claim 1 characterized in that said silica is a silica-titania-chromium tergel, said aging is carried out at a temperature of 18 - 93°C for 1 to 20 hours, said liquid hydroxy-containing organic compound is a C 5 or C 6 alcohol, said inert ambient is nitrogen, said activation is carried out in air, said heat treatment in said inert atmosphere is carried out at a temperature within the range of 427 - 871°C and said activation is carried out at a temperature within the range of 649 - 816°C.
Claim 8
Dependent Claim
27 words
The process of any of claims 1 to 6 characterized in that said aging is carried out at a pH within the range of 7 to 9.
Claim 9
Dependent Claim
54 words
The process of claim 7 characterized in that said pH is maintained within the range of 7 to 9 by means of adding a basic material to said hydrogel; in particular wherein said basic material is selected from ammonia or ammonium hydroxide; in particular wherein said basic material is added prior to said aging.
Claim 10
Dependent Claim
40 words
The process of claim 7 characterized in that said pH is maintained at said value of 7 to 9 by means of utilizing a coordination chromium compound having nitrogen-containing groups; in particular wherein said chromium compound is chloropentamine chromium(III) chloride.
Claim 11
Dependent Claim
94 words
A polymerization process comprising contacting at least one mono-1-olefin having 2 to 8 carbon atoms per molecule with a catalyst under polymerization conditions and recovering a polymer, characterized by using a catalyst according to one of claims 1 to 9; in particular wherein said olefin is selected from ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene; in particular wherein said olefin comprises ethylene; in.particular wherein said polymerization is carried out under slurry conditions; in particular wherein said polymer is an ethylene homopolymer or a copolymer having 98 to 99.6 mole percent polymerized ethylene units.
References Cited (Backward Citations)
No citation records indexed.
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