| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a process for easily and efficiently recovering expensive ruthenium and reusing the recovered ruthenium in preparation of carboxy polysaccharides in the preparation of carboxy polysaccharides by oxidizing polysaccharides using a combination of ruthenium and an oxide. SOLUTION: After polysaccharides are oxidized, a mixed solution is added with an oxidizing agent to bring ruthenium to a highly oxidized state, which is then extracted with a water-insoluble organic solvent. Alternatively, after polysaccharides are oxidized, a mixed solution is heated and added with an oxidizing agent to bring ruthenium to a highly oxidized state, which is subsequently extracted with a water-insoluble organic solvent. The extracted ruthenium at a highly oxidized state is converted into a low oxidized state by a reducing agent and reused in preparation of carboxy polysaccharides.</p> |
