Claims
- 1. In the delignification of lignocellulose material by digestion in a liquid containing an anthraquinone-type compound, the improvement which comprises effecting the delignification in a closed reaction vessel at a maximum temperature in the range from 150.degree. to 200.degree. C. for 0.5 to 480 minutes employing as said anthraquinone-type compound a dinitroanthraquinone in 0.001 to 10% by weight of the lignocellulosic material.
- 2. Process according to claim 1, wherein the dinitroanthraquinone is, 1,5-dinitroanthraquinone, 1,6-dinitroanthraquinone, 1,7-dinitroanthraquinone, 1,8-dinitroanthraquinone, 2,6-dinitroanthraquinone, or 2,7-dinitroanthraquinone.
- 3. Process according to claim 1, wherein the digesting liquid is an alkaline digestion liquid.
- 4. Process according to claim 1, wherein a mixture which contains 0 to 3% by weight of 1-nitroanthraquinone, 5 to 12% by weight of 1,5-dinitroanthraquinone, 15 to 35% by weight of 1,6-dinitroanthraquinone, 15 to 35% by weight of 1,7-dinitroanthraquinone, 15 to 50% by weight of 1,8-dinitroanthraquinone, 0.5 to 3% by weight of 2,6-dinitroanthraquinone and 0.5 to 3% by weight of 2,7-dinitroanthraquinone is used as dinitroanthraquinone compound.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2925544 |
Jun 1979 |
DEX |
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Parent Case Info
This is a continuation of application Ser. No. 158,022, filed June 9, 1980, now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4036680 |
Holten et al. |
Jul 1977 |
|
4178861 |
Vanderhoek et al. |
Dec 1979 |
|
Non-Patent Literature Citations (1)
Entry |
Richter, Textbook of Organic Chemistry 2nd Edition, New York, John Wiley & Sons Inc. |
Continuations (1)
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Number |
Date |
Country |
Parent |
158022 |
Jun 1980 |
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