以桉木机械浆为研究对象，考察了超声功率、超声时间、超声预处理浆质量分数等因素对白度的影响。通过对比在不同超声工艺下浆料漂后白度和残余过氧化氢含量的变换趋势，考察超声波预处理辅助漂白的最优工艺条件。实验结果表明，在超声功率为585 W、频率为22.5 Hz、预处理浆质量分数为2%、预处理时间为30 min的工艺条件下，白度可提高1.7% ISO，残余过氧化氢含量提高了1.4%，桉木机械浆漂白性能得到显著提升。超声预处理通过对纤维的空化作用，增强了药液可及度和浸渍渗透效果。

The influences of ultrasonic power,ultrasonic irritation time and pulp concentration for ultrasound pretreatment on pulp whiteness and physical properties are examined through using mechanical-route eucalyptus pulp as research object.The optimal process conditions for bleaching pulp assisted by ultrasonic pretreatment are investigated by comparing the change trends of the whiteness of pulp and the residual content of hydrogen peroxide after pulp bleaching under different ultrasonic processes.The experimental results show that the whiteness of pulp can be increased by 1.7% ISO and the residual content of hydrogen peroxide rises by 1.4% when the power and frequency of ultrasonic is 585 W and 22.5 Hz respectively,the pulp concentration is 2% and pretreatment lasts for 30min,which translating to a significant improvement of bleaching performance.In addition,the accessibility of the liquid and the effects of impregnation and penetration are enhanced due to cavitation of fibers by ultrasonic pretreatment.

解存欣(1994-),女,硕士研究生,主要从事制浆造纸新技术研究工作,578721996@qq.com