树叶活性炭的制备及表征

Preparation and Characterization of Leaves Activated Carbon

摘要: 活性炭是一种应用广泛的吸附材料，找寻来源广、处理简单的活性炭原材料也一直是人们关注的课题。以树叶为原料制备活性炭，在资源循环利用的同时希望得到高性能活性炭的制备方法。设计正交试验对活性炭的比表面积、微孔面积以及甲醇饱和吸附量进行分析，得到磷酸法制备树叶活性炭的最佳条件为：质量分数50%的磷酸与树叶浸渍比3:1条件下浸渍12小时，350℃活化1小时。表征结果显示，活性炭比表面积为774.4 m²/g，微孔面积148.2 m²/g，孔径结构以中孔为主；表面官能团以酸性官能团为主，占官能团总含量的95.3%，酸性官能团主要为醇羟基和酚羟基；等电点为5.33。

Abstract: Activated carbon is an adsorbent material widely used, and it has been the subject of much atten-tion to look for a kind of raw materials which has a multiple source and is easy to process. The leaves were used as raw materials to produce activated carbon. With the resource recycling, a preparation method of high performance activated carbon was also hoped to get. This study ana-lyzed the special surface area, micropore area and toluene adsorption capacity of leaves activated carbon by orthogonal test, and finally got the best preparation method: 50% mass fraction of H3PO4 and leaves in an impregnation ratio of 3:1 for 12 hours, and then in an activated temperature of 400˚C for 1 hour. And the result of characterization showed that the special surface area and the micropore area of leaves activated carbon were 774.4 m²/g and 148.2 m²/g, respectively, and the main structure of leaves activated carbon was mesopore. 95.3% of the functional groups in the activated carbon’s surface were the acidic functional groups, which mainly included alcoholic hydroxide groups and phenolic hydroxyl groups. The isoelectric point of the leaves activated carbon was 5.33.