Claims
- 1. A process for cooking lignocellulosic materials which comprises heating the lignocellulosic materials to a temperature between 150.degree. C. and 200.degree. C. in a cooking solution containing caustic soda and 0.01% to 10% by weight of 1,2,3,4-tetrahydro-9,10-anthracene-diol based on the weight of the dry lignocellulosic material to produce a paper pulp.
- 2. A process according to claim 1, in which the cooking solution contains 0.05% to 2% by weight of 1,2,3,4-tetrahydro-9,10-anthracenediol based on the weight of the dry lignocellulosic material.
- 3. A process according to either of claims 1 or 2, in which the cooking solution contains an alkali metal sulfide, 10 to 25% by weight of caustic soda based on the weight of the dry lignocellulosic material, and in which the weight ratio of cooking solution to dry lignocellulosic material is between about 3 and 6.
- 4. A process according to either of claims 1 or 2 in which the cooking solution contains an alkali metal sulfide, an amount of active alkali of 10% to 25% by weight based on the weight of the dry lignocellulosic material, a sulfidity of 15% to 30% by weight based on the weight of the active alkali, and in which the weight ratio of cooking solution to dry lignocellulosic material is between about 3 and 6.
Priority Claims (1)
Number |
Date |
Country |
Kind |
78 22218 |
Jul 1978 |
FRX |
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Parent Case Info
This is a continuation of application Ser. No. 274,757, filed June 18, 1981, now abandoned which is a continuation of application Ser. No. 57,987, filed July 16, 1979, now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4012280 |
Holton |
Mar 1977 |
|
4036680 |
Holton et al. |
Jul 1977 |
|
4181565 |
Nakamura et al. |
Jan 1980 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
52-155202 |
Dec 1977 |
JPX |
54-100332 |
Aug 1979 |
JPX |
Continuations (2)
|
Number |
Date |
Country |
Parent |
274757 |
Jun 1981 |
|
Parent |
57987 |
Jul 1979 |
|