Oxidative manufacture of pulp with chlorine dioxide
Abstract
Abstract A PROCESS FOR PRODUCING PAPERMAKING PULP BY FIRST PRECONDITIONING THE INITIAL WOOD MATERIALS, BY LACERATING THE MATERIALS AT A TEMPERATURE ABOVE THE THERMAL SOFTENING POINT OF THE LIGNIN THEREIN INTO FIBER BUNDLES, AND SECOND DELIGNIFYING THE LACERATED MATERIAL. THE DELIGNIFICATION INCLUDES DIGESTING THEMATERIALS WITH AN OXIDATIVE CHEMICAL SUCH AS CHLORINE DIOXIDE, PERACIDS, OZONE, OR NOBLE GAS OXIDES, EXTRACTION OF SOME OF THE LIGNIN BY ALKALINE TRATMENT, AND OPTIONAL FURTHER DEFIBRATION VIA MECHANICAL OR CHEMICAL TREATMENT. THE PREFERRED OXIDATIVE CHEMICAL IS CHLORINE DIOXIDE, AND THE OXIDATIVE TREATMENT IS TERMINATED WHEN THE RESIDUAL LIGNIN CONTENT TO THE WOOD MATERIAL, MEASURED AS KLASON LIGNIN, IS ABOVE 50% OF THE ORIGNAL KLASON LIGNIN CONTENT.
Inventors
- 👤 N Thompson
- 👤 G Nicholls
- 👤 S Han
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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