棉短绒酸水解乙醇法制备微晶纤维素

Manufacturing Microcrystalline Cellulose with Acid-Catalyzed Ethanol Pulping of Cotton Linter

对棉短绒制备微晶纤维素的工艺进行研究,主要对酸催化乙醇法制浆工艺的加乙酸量、液比和保温时间对浆料高锰酸钾值、得率、漂后浆料的白度、α-纤维素含量和高锰酸钾值的影响进行了研究;对制备MCC酸水解工艺的液比、水解温度、水解时间进行研究。结果表明:液比和保温时间对降低棉短绒高锰酸钾值的贡献最显著,加酸量也有一定的影响。棉短绒酸催化乙醇法最佳制浆工艺为:加乙酸量1%,液比1:8,保温时间60min。该制浆条件下棉短绒乙醇浆高锰酸钾值为8.7,得率81.93%,经EAPP漂白后浆料的高锰酸钾值为3.3,α-纤维素含量为92.48%,白度为86.56%ISO;酸水解制备微晶纤维素的最佳工艺条件为:液比1:7、水解温度60℃、水解时间40min、5%稀碱处理温度80～90℃、碱处理时间40min。

The technology of cotton linter which was used to make microcrystalline cellulose was investigated.The central researchw as studying the effiects of acetic acid addition,the yield-to-feedstock ratio and holding time,as well as the effiects of the whiteness,α -cellulose content and KMnO4 number after bleaching;and studying the yield-to-feedstock ratio,hydrolysis temperature,h ydrolysis time of acid hydrolysis technology to make MCC.e experiment results showed that the contribution to the decreaseo f KMnO4 number was more prominent with the yield-to-feedstock ratio and holding time than the acid addition.The optimalc ondition of acid-catalyzed ethanol pulping of cotton linter is as follows：acetic acid addition 1%,the yield-to-feedstock ratio 1：8,h olding time 60 minutes.Under these conditions the KMnO4 number of cotton linter ethanol pulp was 8.7,the yield 81.93%,anda fter EAPP bleaching the KMnO4 number was 3.3,α-cellulose content 92.48%,whiteness 86.56.The optimal preparation process of microcrystalline cellulose condition is as follows：the yield-to-feedstock ratio is 1：7,hydrolysis temperature 60℃,hydrolysis time 40m in,5%dilute alkali treatment temperature 80～90℃,alkali processing time 40 min.