Abstract: The concentration of furfural is relatively low(about 30g/L)in its industrial production process. Compared with the traditional distillation method,adsorption can reduce energy consumption. The macroporous resin materials for adsorption have been reported but the adsorption capacity is very limited for furfural. In this study,the large pore hydrophobic metal azolate framework(MAF-6)was used in the adsorptive separation of furfural-water solution. The static adsorption isotherms,static adsorption kinetics and fixed-bed dynamic breakthrough curves of MAF-6 were determined for pure furfural. The experimental results showed that adsorption capacity of MAF-6 was 260mg/g for furfural due to its large Langmuir specific surface area(1582m²/g)and pore volume(0.63cm³/g). The adsorption process of MAF-6 was well described with the Langmuir adsorption model and the adsorption equilibrium time was 45min for furfural. It is because the pore aperture(7.6Å)of MAF-6 is greater than the kinetic diameter of furfural(5.7Å)that makes the pseudo-second-order model fit the experimental data than the pseudo-first-order model. In the fixed-bed breakthourgh experiments,the effect of bed height and flow rate were studied and the Yoon-Nelson model can well describe the breakthrough process of MAF-6 for furfural.

Key words: furfural, adsorption, isotherm modeling, kinetic modeling, fixed-bed

摘要： 在糠醛的生产过程中，糠醛的浓度比较低（约为30g/L），与传统精馏法相比，吸附法能有效降低能耗，文献报道的吸附材料多集中在大孔树脂材料，但其吸附容量有限。本研究将憎水性的金属多氮唑骨架材料（MAF-6）用于吸附分离稀糠醛-水溶液体系，分别考察了MAF-6对单组分糠醛的静态吸附等温线、静态吸附动力学和固定床动态穿透曲线。实验结果表明：由于MAF-6具有较大Langmuir比表面积（1582m²/g）和孔容（0.63cm³/g），在25℃下，MAF-6对糠醛的平衡吸附量为260mg/g，而且考察了不同温度对吸附等温线的影响，即温度越高，吸附容量越低。朗格缪尔吸附模型比弗伦德里希吸附模型更好地符合等温吸附过程；由于MAF-6具有较大的孔径（7.6Å），大于糠醛的动力学直径（5.7Å），在25℃下，MAF-6对糠醛的吸附平衡时间为45min，而且准二级动力学模型比准一级动力学模型更好地描述动力学吸附过程；对于固定床动态穿透实验，分别考察了不同填料高度和不同流速的影响，而且Yoon-Nelson模型可以较好地模拟MAF-6对糠醛的固定床吸附过程。

关键词: 糠醛, 吸附, 等温线模型, 动力学模型, 固定床