Valley打浆预处理制备微晶纤维素

Preparation of Microcrystalline Cellulose by Valley Beating Pretreatment

关键词:  Valley打浆  预处理  微晶纤维素  可及性

Key Words:Valley beating  pretreatment  MCC  accessibility

摘要:为加快酸液对纤维素的渗透效率，提高酸水解反应平均速率，减少酸用量、缩短酸水解反应时间，本研究以针叶木溶解浆为原料，通过Valley打浆机对纤维原料进行预处理，探讨Valley打浆对盐酸水解产物微晶纤维素（MCC）质量的影响。结果表明，Valley打浆后MCC平均粒径随打浆度的提高逐渐减小，打浆度为53°SR时，平均粒径由52.116 μm降低至38.675 μm，且粒径分布更加集中，MCC结晶度变化不大。采用响应面法优化得到Valley打浆和酸水解最佳工艺，在保证MCC粒径和结晶度与未打浆预处理相近的情况下，Valley打浆后酸液用量减少了16.67%，反应时间缩短了42.86%。由此可知，Valley打浆预处理可以提高酸液对纤维素的可及性，实现了对MCC粒径的有效调控，同时降低酸水解负荷。

Abstract:In order to speed up the penetration of acid to cellulose, increase the average rate of acid hydrolysis, thus reduce the amount of acid used and shorten the reaction time in preparation of microcrystalline cellulose, softwood dissolving pulp was used as raw material and pretreated by Valley beating. The effect of Valley beating on the quality of microcrystalline cellulose produced by acid hydrolysis was studied. The results showed that compared with raw materials without beating, the average particle size of MCC decreased gradually with the increase of beating degree, when the beating degree was 53°SR, the average particle size decreased from 52.116 μm to 38.675 μm, the particle size distribution was more concentrated, and the crystallinity of MCC did not change much. The conditions of Valley beating and acid hydrolysis were optimized by using response surface method, the particle size and crystallinity of MCC prepared basically remained the same, the amount of acid used was reduced by 16.67%, and the reaction time was shortened by 42.86%.It indicated that the pretreatment of Valley beating could improve the accessibility of acid to cellulose, achieve effective control of MCC particle size while reducing acid hydrolysis pollutant load.