AS-AQ法制备高聚合度三桠皮纸浆的蒸煮工艺研究

Research on the Pulping Process for Preparing Edgeworthia chrysantha Pulp with High Degree of Polymerization by AS-AQ Method

关键词:  三桠皮  AS-AQ法  聚合度  蒸煮

Key Words:Edgeworthia chrysantha  AS-AQ method  degree of polymerization  cooking

摘要:本研究以三桠皮为原料，制备高聚合度纸浆，比较了烧碱（NaOH）法、烧碱-蒽醌（NaOH-AQ）法、硫酸盐（KP）法及碱性亚钠-蒽醌（AS-AQ）法4种方法制得纸浆的性能。结果表明，采用AS-AQ法蒸煮得到的三桠皮纸浆聚合度最高，且纸浆得率及白度较高，纤维长宽比大。采用响应面分析实验优化出高纤维素聚合度三桠皮纸浆较适宜的工艺条件为：用碱量13.9%、亚硫酸化度54.7%、最高温度137 ℃、升温时间1.5 h、保温时间2.5 h、液比1∶6。在该条件下制得的三桠皮纸浆聚合度为1 942，R16得率为35.0%，纤维长宽比为189，抄造纸张的白度为63.1%，抗张指数、耐破指数和撕裂指数分别为42.0 N·m/g、2.55 kPa·m²/g和22.0 mN·m²/g。AS-AQ法蒸煮能够在保证纸浆得率的同时有效提高纤维素聚合度，为高附加值纸浆产品的开发提供了技术依据。

Abstract:In this study， using Edgeworthia chrysantha as the raw material to prepare pulp with a high degree of polymerization， four differernt cooking methods were compared， including caustic soda （NaOH） method， caustic soda-anthraquinone （NaOH-AQ） method， kraft （KP） method and alkaline sodium sulfite-anthraquinone （AS-AQ） method. The results showed that the degree of polymerization of Edgeworthia chrysantha pulp after AS-AQ method cooking was the highest， and the pulp yield and whiteness were relatively high， with a large fiber length-to-width ratio. By the means of response surface analysis experiments， more suitable process conditions for preparing Edgeworthia chrysantha pulp with a high degree of polymerization were optimized as follows： the alkali dosage of 13.9%， the degree of sulfitation of 54.7%， the maximum temperature of 137 ℃， the heating-up time of 1.5 h， the holding time of 2.5 h， and the liquid-to-solid ratio of 1∶6. Under these conditions， the yield of R16 of Edgeworthia chrysantha pulp was 35.0%， the degree of polymerization reached up to 1 942， the fiber length-to-width ratio was 189， and the whiteness of the paper was 63.1%. Then the tensile index， burst index， and tear index were 42.0 N·m/g， 2.55 kPa·m²/g， and 22.0 mN·m²/g， respectively. Thus， it could be seen that AS-AQ method cooking here could effectively increase the degree of polymerization while ensuring the pulp yield， providing a technical basis for the development of pulp products with high added value.