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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 process of preparing microcrystalline cellulose from cotton linter was studied. The effects of acetic acid amount, liquid ratio and holding time on the potassium permanganate value, yield, Whiteness, α-cellulose content and potassium permanganate value were studied. The liquid ratio, hydrolysis temperature and hydrolysis time of MCC acid hydrolysis process were studied. The results showed that the ratio of liquid and holding time had the most significant contribution to reducing the value of potassium permanganate in cotton linter, and the amount of acid addition also had a certain influence. Cotton linter acid catalyzed ethanol best pulping process: plus acetic acid content of 1%, liquid ratio of 1: 8, holding time 60min. Under this condition, the value of potassium permanganate in cotton linter pulp was 8.7 and the yield was 81.93%. The potassium permanganate value of pulp after EAPP bleaching was 3.3, the content of α-cellulose was 92.48% and the whiteness was 86.56% ISO. The optimal conditions for the preparation of microcrystalline cellulose by acid hydrolysis are as follows: liquid ratio 1: 7, hydrolysis temperature 60 ℃, hydrolysis time 40min, 5% dilute alkali treatment temperature 80 ~ 90 ℃, alkali treatment time 40min.