有机酸改性对活性炭及其甲醇吸附与再生的影响  

Effects of organic acid modification on activated carbon and its adsorption of methanol and regeneration

作　　者：梁鑫[1] 李立清[1] 

机构地区：[1]中南大学能源科学与工程学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2015年第11期4316-4324,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(20976200;21376274);APEC科技产业合作基金资助项目(313001022)~~

摘　　要：以颗粒活性炭为原料,采用3种有机酸(草酸、酒石酸和柠檬酸)为改性剂制得改性活性炭。采用比表面积及孔径分析仪、扫描电子显微镜及傅里叶转换红外光谱仪考察改性对活性炭物化性质的影响。从平衡吸附量、吸附动力学以及吸附能角度,探讨改性对活性炭在不同温度、不同进气质量浓度下对甲醇吸附行为的影响。对吸附饱和的活性炭进行再生实验,考察再生过程中脱附速率的变化,并对再生活性炭进行同等条件下的吸附实验。研究结果表明:改性后,活性炭BET比表面积及总孔容减小,表面有不均匀的粗糙的刻蚀痕迹,同时伴随有白色晶体颗粒生成,表面生成更多的O—H,C=O和C—O等含氧官能团。平衡吸附量由大到小顺序为:AC-OA,AC-TA,AC-0,AC-CA;Bangham动力学模型最适合描述活性炭对甲醇的吸附动力学过程,其拟合的相关系数R2均高于0.998;改性后,活性炭对甲醇的吸附能均增大。与新鲜活性炭相比,再生活性炭吸附性能变化不大,再生方法基本可行。The modified activated carbon （AC） was obtained from granular activated carbon by using oxalic acid, tartaric acid and citric acid as modification agent respectively. By using Specific surface area and pore distribution analyzer, Scanning electron microscope and Fourier transformed infrared spectroscopy, the effects of modification on physicochemical properties of activated carbons were studied. From the perspective of equilibrium adsorption capacity, adsorption kinetics, and adsorption energy, the effects of modification on the adsorption behaviours of methanol onto activated carbons at different temperatures and inlet concentrations were researched. The regeneration experiments of saturated-adsorption activated carbons were carried out, and the change of desorption rate in the regeneration process was investigated. The results show that after modification, the BET specific surface area and total pore volume of activated carbons decrease, uneven rough etching trace and white crystal particles are found on the surface of activated carbon, and more oxygen-containing functional groups such as O--H, C=O, C--O, etc. are also formed on the surface. The order （from big to small） of equilibrium adsorption capacity is AC-OA, AC-TA, AC-0, AC-CA; Bangham kinetics model best describe the adsorption kinetics process of methanol onto activated carbon, and the fitting correlation coefficients are all bigger than 0.998; after modification, the adsorption energies of activated carbons for methanol increase. By adsorption experiments of regenerated activated carbons under same conditions, it is found that the adsorption properties of regenerated activated carbons changed little compared with fresh activated carbon, and that the regeneration method is basically feasible.

关 键 词：有机酸 改性活性炭 吸附 甲醇 再生 

分 类 号：O613.71[理学—无机化学]