Mg（OH）2粒径对辐射松氧脱木素的影响

Effect of the Particle Size of Mg（OH）2 on the Oxygen Delignification of Radiata Pine Kraft Pulp

为进一步探讨镁盐作为纤维素保护剂的作用机制,研究了纸浆氧脱木素过程中添加不同粒径(20、50、100、200、500 nm)的Mg(OH)2对添加多种过渡金属离子(Cu^2+、Mn^2+和Fe^3+)的辐射松硫酸盐浆氧脱木素的影响,通过测定氧脱木素后纸浆卡伯值和黏度,分析不同粒径Mg(OH)2对纤维素的保护效果。研究结果表明,在纸浆氧脱木素过程中,不同粒径的Mg(OH)2对纸浆卡伯值、木素脱除率没有显著影响;但小粒径的Mg(OH)2对纸浆黏度的保护能力要优于大粒径的Mg(OH)2。氧脱木素中添加Mg(OH)2粒径越小,纸浆黏度降低越少,手抄片物理强度越大。

To further explore the mechanism of magnesium salt as a cellulose protectant in oxygen delignification,different particle sizes(20,50,100,200,500 nm)of Mg(OH)2 were added in the oxygen delignification system,various transition metal ions(Cu^2+,Mn^2+and Fe^3+)were introduced into the pulp before the addition of magnesium salts.The effects of Mg(OH)2 on the pulp viscosity and Kappa numbers were studied.The results showed that Mg(OH)2 with different particle sizes had no significant effects on Kappa number and lignin removal rate during oxygen delignification.However,the smaller particle size of Mg(OH)2 had superior pulp viscosity protection ability than the bigger particle size.The smaller particle size of Mg(OH)2 was added in oxygen delignification,the pulp had lower viscosity reduction and greater handsheet physical strength.