枫香树材清洁制浆技术

The Low Pollution Pulping of Maple

对速生阔叶木枫香树材的纤维形态、主要化学组成、清洁制浆及绿色漂白工艺进行了一系列探讨。结果显示,枫香木纤维平均长度较长,长宽比均比杨木大,且其综纤维素和戊聚糖含量高而Klason木素含量低,是一种很有发展潜力的制浆造纸原料。采用硫酸盐法制浆,蒸煮后所得细浆得率为49.9%,卡伯值为23.0,白度为23.8%ISO,黏度为734.7 mL/g。利用环境友好型漂白法——氧脱木素技术处理该枫香树材硫酸盐浆,并在此过程中创造性地使用助剂蒽醌。四因素三水平正交试验结果表明:用碱量、氧压、温度和时间对枫香树材硫酸盐浆添加蒽醌氧脱木素后浆料的性能均有很大的影响。其中,温度对得率、卡伯值、白度和黏度等的影响最大,时间对卡伯值、白度和黏度的影响最小。枫香树材硫酸盐浆添加蒽醌氧脱木素的较为适宜的工艺为:用碱量3%,氧压0.7 MPa,温度105℃,保温时间90 min,浆浓20%,MgSO4用量0.5%,蒽醌用量0.1%。在该条件下所得浆料得率90.7%,卡伯值7.0,黏度545.1 mL/g,白度51.0%ISO,脱木素选择性8.42×10-2。与相同条件下常规氧脱相比,卡伯值和白度相近,但得率、黏度和脱木素选择性都有所提高。蒽醌在枫香树材硫酸盐浆氧脱木素过程中可保护碳水化合物,提高脱木素选择性,是一种良好的氧脱木素助剂。

This study was focused on the fiber morphology, chemical composition, and low pollution pulping and bleaching of Maple. The results showed Maple is a great pulp and paper-making material, because of its higher fiber length and the length/width ratio, higher contents of holocellulose and pentosan, but lower contents of Klason lignin. After kraft pulping, the Maplekraft pulp was obtained with screened pulp yield of 49.9%, Kappa number of 23.0, brightness of 23.8%ISO and intrinsic viscosity of 734.7 mL/g. An L9（3^4） orthogonal test was then designed tostudy the oxygen delignification with anthraquinone （AQ） of Maple kraft pulp. In this part, the effects of four factors on the oxygen delignification with AQ of Maple kraft pulp were analyzed.The optimal oxygen delignification conditions with AQ were determined as alkali charge was 3% with oxygen delignification of 0.5 MPa at 120℃ for 85 min. At these optimal conditions, theoxygen delignified Maple pulp was obtained with the yield 90.7%, Kappa number 7.0, intrinsic viscosity 545.1 mL/g, brightness 51.0%ISO and delignification selection 8.42 × 10^-2. In contrast toconventional oxygen delignification without AQ, the pulp yield, intrinsic viscosity and delignification selection were all increased. So AQ is a good oxygen delignification additivewhich can protect carbohydrate, although cannot enhance the delignification.