咖啡壳纤维素提取工艺的优化及其微观结构  

Optimization of extracting technology for coffee cellulose and characterization of its microstructure

作　　者：王宇[1,2] 李如燕[1,2] 李根[2] 张松[1,2] 

机构地区：[1]昆明理工大学材料科学与工程学院,云南昆明650093 [2]固体废弃物资源化国家工程研究中心,云南昆明650093

出　　处：《化工进展》2017年第6期2262-2269,共8页Chemical Industry and Engineering Progress

摘　　要：为扩展咖啡壳资源化再利用的新用途,以废弃咖啡壳为原料,采用化学分离方法提取纤维素,通过单因素实验和正交实验,确定了咖啡壳纤维素提取的最优工艺条件,即NaOH质量分数为4%、H_2O_2质量分数为10%、反应温度为40℃、反应时间为35min时,所提取的咖啡壳纤维素产量最佳,可达83.88%。采用FITR、SEM、XRD、吸液性能测试等手段分别对提取样品的成分、微观形貌、物相构型和吸液倍率进行了表征。结果表明:提取的样品成分中主要含有纤维素;提纯后的纤维素具有螺旋管状结构,其比表面积明显增大,而晶体类型没有发生变化,仍然为天然纤维素Ⅰ晶型;在室温条件下,咖啡壳纤维素在自来水中的吸液倍率最大(可达65g/g),在0.9%NaCl溶液中的吸液倍率最低(约为58g/g),明显都高于天然棉纤维素的吸液倍率(40g/g)。As a new recycling material, the coffee shell was used as a raw material to extract the cellulose by adopting the chemical separation techniques. Single factor experiment and orthogonal experiment were conducted to find the optimal process condition of the extracting process. The results showed that the optimal conditions of cellulose extraction were as follows. NaOH mass fraction 4%, H2O2 mass fraction 10%, and reacting at 45℃ for 35min. The optimal mass fraction （83.88%） of the coffee shell cellulose was obtained under these conditions. The extracted samples＇ composition, micro-surface structure, phase structure and absorbency were tested by FTIR, SEM, XRD and absorbent liquid experiment. The results showed that the extracted samples were mainly cellulose and had spiral tube structure. Its specific surface area increased significantly and the crystal type, natural cellulose I, did not change. At room temperature, the absorption rate （65g/g） coffee shell cellulose was largest with the tap water, and the absorption rate （58g/g） was lowest with 0.9% NaCl solution , which was stillhigher than natural cotton cellulose （40g/g） .

关 键 词：咖啡壳 纤维素 提取 吸液性能 

分 类 号：TQ353.4[化学工程]