Al-MCM-41介孔分子筛吸附喹啉的性能

在碱性条件下,采用水热晶化法,以偏硅酸钠为硅源,铝酸钠为铝源,CTAB为结构模板剂,成功合成出了含铝介孔分子筛Al-MCM-41。采用XRD、BET等手段对合成的Al-MCM-41进行表征,对柴油中的氮化物喹啉进行了吸附实验,考察了Al-MCM-41介孔分子筛对氮化物喹啉的吸附能力,探究了硅铝比为60的Al-MCM-41分子筛对喹啉溶液吸附的热力学和动力学行为,测得353.15～393.15 K 温度范围内的吸附等温线数据,用Langmuir、Freundlich方程对此进行拟合,并根据热力学原理计算得到吸附过程中的ΔH、ΔG、ΔS值和吸附表观活化能。结果表明, 硅铝比为60的Al-MCM-41具有较大的孔容、比表面积和较窄的孔径分布,结晶度和有序性高。等温吸附平衡符合Freundlich 等温线模型,其ΔH -0.7682 kJ·mol^-1,ΔG -28.1215 kJ·mol^-1, ΔS 73.2434 J·mol^-1·K^-1,吸附动力学符合Pseudo拟二级方程,E_a为2.8575 kJ·mol^-1。

Adsorption of quinoline on zeolite Al-MCM-41

Under basic conditions, Al-containing mesoporous zeolite Al-MCM-41 was successfully synthesized by hydrothermal synthesis method using sodium metasilicate as silica source, sodium aluminate as alumina source and CTAB as templating agents. XRD and BET were used to investigate the characterization of Al-MCM-41. The adsorptive capacity of this mesoporous zeolite for quinolone was analyzed through adsorption experiment for the nitrogen compounds in diesel in a continuous fixed bed reactor. The thermodynamic performance of the adsorption process was investigated in the range from 353.15 K to 393.15 K. Langmuir and Freundlich isothermal adsorption models were employed to fit the experimental data. The results of characterization showed that Al-MCM-41 with Si/Al 60 had larger pore volume, specific surface area and narrow pore distribution. The mesoporous molecular sieve had good crystallization degree and ordered pore structure. The adsorption of quinoline on zeolite Al-MCM-41 with Si/Al 60 was in accordance with the Freundlich isothermal adsorption model. The thermodynamic parameters, such as ΔH, ΔG, ΔS and apparent activation energy, were calculated to be -0.7682 kJ·mol^-1, -28.1215 kJ·mol^-1, 73.2434 J·mol^-1·K^-1 and 2.8575 kJ·mol^-1, respectively. Pesto-second order rate equation was better to describe adsorption of quinolone.