US4581208A
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Lowering organic contaminant content in a sodium aluminate solution by oxidation in a packed bed
Assignee: Alcoa Corp
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Filing: 1985-06-26
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Granted: 1986-04-08
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Expires: 2005-06-26
Abstract
Abstract Wet oxidation of organic contaminants in aqueous sodium aluminate solutions is enhanced when a heated and oxygenated solution is passed through a packed bed containing a metal packing member that is chemically inert to sodium aluminate solutions at elevated temperatures. Process temperature is about 180 DEG -300 DEG C. and oxygen partial pressure is at least about 345 kPa. The packed bed has a packing surface of at least 100 square meters per cubic meter bed volume and preferably at least 50% free space.
Inventors
- 👤 Paul J. The
- 👤 Fred S. Williams
- 👤 Thinnalur J. Sivakumar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:03
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/02; C01F7/46; C01F7/47; C01F7/473; C01F7/476
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
131 words
A process for lowering the concentration of organic contaminants in a sodium aluminate solution, comprising (a) contacting a sodium aluminate solution containing organic contaminants with a gas comprising molecular oxygen at a partial oxygen pressure of at least about 345 kPa, (b) heating the oxygenated solution to a temperature of about 180°-300° C., (c) passing the heated and oxygenated solution through a packed bed containing a metal packing member comprising nickel or an alloy containing at least about 45 wt% nickel, said packing member being chemically inert to sodium aluminate solution at temperatures of at least 300° C., said packed bed having a packing surface a p of at least 100 square meters per cubic meter bed volume, and (d) recovering sodium aluminate solution having a lower content of organic contaminants.
Claim 2
Dependent Claim
131 words
A process for lowering the concentration of organic contaminants in a sodium aluminate solution, comprising (a) contacting a sodium aluminate solution containing organic contaminants with a gas comprising molecular oxygen at a partial oxygen pressure of at least about 345 kPa, (b) heating the oxygenated solution to a temperature of about 180°-300° C., (c) passing the heated and oxygenated solution through a packed bed containing a metal packing member comprising nickel or an alloy containing at least about 45 wt% nickel, said packing member being chemically inert to sodium aluminate solution at temperatures of at least 300° C., said packed bed having a packing surface a p of at least 100 square meters per cubic meter bed volume, and (d) recovering sodium aluminate solution having a lower content of organic contaminants.
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein the packing member comprises a Raschig ring, Lessing ring, partition ring or Pall ring.
Claim 4
Dependent Claim
17 words
The process of claim 2 wherein said packing member comprises a plurality of randomly arranged packing members.
Claim 5
Dependent Claim
15 words
The process of claim 1 wherein said packing member comprises a plurality of Raschig rings.
Claim 6
Dependent Claim
19 words
The process of claim 4 wherein said Raschig rings comprise hollow cylinders having a diameter of about 0.6-5 cm.
Claim 7
Dependent Claim
18 words
The process of claim 1 wherein said packed bed has a free space of at least about 50%.
Claim 8
Dependent Claim
13 words
The process of claim 1 wherein said packing member comprises a nickel-copper alloy.
Claim 9
Dependent Claim
17 words
The process of claim 1 wherein said solution is passed through said bed co-currently with said gas.
Claim 10
Dependent Claim
17 words
The process of claim 1 wherein said solution is heated to a temperature of about 225°-300° C.
Claim 11
Dependent Claim
16 words
The process of claim 1 wherein said partial oxygen pressure is at least about 650 kPa.
Claim 12
Dependent Claim
16 words
The process of claim 1 wherein said partial oxygen pressure is at least aobut 1300 kPa.
Claim 13
Dependent Claim
22 words
The process of claim 1 wherein said solution has an initial organic carbon content of at least about 10 grams per liter.
Claim 14
Dependent Claim
24 words
The process of claim 1 wherein said solution has a total alkali content of about 100-350 g/l (expressed as Na 2 CO 3 ).
Claim 15
Dependent Claim
149 words
A process for lowering the concentration of organic contaminants in a sodium aluminate solution, comprising (a) contacting an aqueous sodium aluminate solution containnig at least about 10 g/l organic contaminants with a gas comprising molecular oxygen at a partial pressure of at least about 1300 kPa, (b) heating the oxygenated solution to a temperature of about 245°-300+ C., (c) passing the solution and the gas co-currently through a packed bed containing a packing member comprising nickel or an alloy of nickel containing at least about 45 wt% nickel, said packing member being chemically inert to aqueous sodium aluminate solution at temperatures of at least 300° C., said packed bed having a packing surface a p of at least 200 square meters per cubic meter bed volume and a free space of at least about 50%, and (d) recovering aqueous sodium aluminate solution having a lower content of organic contaminants.
Claim 16
Dependent Claim
149 words
A process for lowering the concentration of organic contaminants in a sodium aluminate solution, comprising (a) contacting an aqueous sodium aluminate solution containnig at least about 10 g/l organic contaminants with a gas comprising molecular oxygen at a partial pressure of at least about 1300 kPa, (b) heating the oxygenated solution to a temperature of about 245°-300+ C., (c) passing the solution and the gas co-currently through a packed bed containing a packing member comprising nickel or an alloy of nickel containing at least about 45 wt% nickel, said packing member being chemically inert to aqueous sodium aluminate solution at temperatures of at least 300° C., said packed bed having a packing surface a p of at least 200 square meters per cubic meter bed volume and a free space of at least about 50%, and (d) recovering aqueous sodium aluminate solution having a lower content of organic contaminants.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 7.5 Years (Year 8) | 1993-04-07 | 1993-10-07 | 1994-04-08 | $3760.00 | Window Closed / Lapsed |
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