OXIDATIVE DAMAGE OF PULP CELLULOSE DURING DIFFERENT BLEACHING OPERATIONS
An oxidative damage at pulp cellulose is not desirable but unavoidable during pulp bleaching. The oxidation at C6 hydroxyl group results in a formation of C6-aldehyde and/or C6-carboxyl (glucuronic acid)structure. There is however not a simple and routine method available for quantification of the oxidised structures. In the present paper, methanolysis after a 72% sulphuric acid pre-solubilisation in combination of acetylation followed by GC-MS has been set up for quantification of the uronic acid structures in cellulose. Industrial birch and spruce kraft pulps were analysed after each oxidation operation in TCF and ECF bleaching sequence respectively. It was concluded that C6 carboxyl group exist in all the pulps tested. Oxygen delignification and (PO) stage generates more glucuronic acid structure in the softwood and the hardwood respectively. Galacturonic acid content was also increased during oxygen delignification of the spruce kraft pulp.
ozidative damage Ozygen delignification spuce kraft pulp bleaching
Li Jiebing Goran Gellerstedt
Department of Fibre and Polymer Technology, Royal Institute of Technology, KTH, SE-10044 Stockholm, Sweden
国际会议
广州
英文
315-320
2006-11-08（万方平台首次上网日期，不代表论文的发表时间）