Process for manufacturing cellulose xanthate and viscose prepared from said cellulose xanthate
Abstract
Abstract VISCOSE MANUFACTURING PROCESS. AGED ALKALI CELLULOSE CONTAINING 20-36 WT. PERCENT CELLULOSE AND MORE THAN 14 WT. PERCENT NAOH IS RE-STEEPED WITH A SODIUM HYDROXIDE SOLUTION CONTAINING LESS THAN 15% BY WEIGHT NAOH AND PRESSED TO REDUCE THE AMOUNT OF NAOH IN THE ALKALI CELLULOSE, YIELDING A SECOND ALKAI CELLULOSE CONTAINNG LESS THAN 14% BY WEIGHT NAOH AND AT LEAST 24% BY WEIGHT CELLULOSE BASED ON THE TOTAL WEIGHT OF SAID SECOND ALKALI CELLULOSE. THE SECOND ALKALI CELLULOSE IS XANTHATED WITH CARBON DISULFIDE. THE AMOUNT OF CARBON DISULFIDE REQUIRED FOR XANTHATION BASED ON THE TOTAL WEIGHT OFTHE CELLULOSE IN THE ALKALI CELLULOSE IS VERY LOW ANDFOR RAYON STAPLE AND CELLOPHANE MAY BE AS LOW AS 14-24% DUE TO THE LOW AMOUNT OF SODIUM HYDROXIDE ANDTHE HIGH AMOUNT OF CELLULOSE PRESENT IN THE ALKALI CELLULOSE. THE XANTHATE IS THEREAFTR DISSOLVED IN DILUTE SODIUM HYDROXIDE OR WATER TO YIELD VISCOSE.
Inventors
- 👤 H Sihtola
- 👤 B Nizovsky
Bibliographic Details
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