Synthesis and the performance of Co-MOF-74 for n-hexane/1-hexene adsorption separation

doi:10.16085/j.issn.1000-6613.2019-0683

Abstract

Abstract: Co-MOF-74 was synthesized through solvothermal process. Samples were characterized by using XRD, N₂ adsorption, FTIR, TG-DSC and SEM. In addition, the adsorption performances for n-hexane/1-hexene were evaluated. The optimal synthesis conditions were observed as follows:the ratio of raw materials of n[Co (NO₃) ₂·6H₂O]:n (DHTP):n (THF):n (H₂O)=2:1:165:750, crystallization temperature of 100℃, crystallization time of 24h, activation temperature of 150℃, activation time of 2h. It is indicated that synthesized Co-MOF-74 has static adsorption capacities of 125.6mg/g and 72.9mg/g for 1-hexene and n-hexane, respectively. The BET specific surface area, pore volume and average micropore size are 1209m²/g, 0.41cm³/g and 0.66nm, respectively. The maximum adsorption amount is determined to be around 130mg/g at adsorption temperature range of 283K to 313K. Furthermore, the adsorption isotherms for 1-hexene on Co-MOF-74 can be explained by using L-F model very well. 1-hexene adsorption onto Co-MOF-74 is confirmed to be a spontaneous exothermic process.

Key words: synthesis, adsorption, alkane, separation

摘要： 采用溶剂热方法合成了Co-MOF-74，采用X射线衍射（XRD）、氮气吸附、红外光谱（FTIR）、热重-差热分析（TG-DSC）和扫描电子显微镜（SEM）对其进行表征，研究其吸附正己烷/1-己烯性能。结果表明，优化的Co-MOF-74合成工艺条件为：原料配比n[Co（NO₃）₂·6H₂O]：n（DHTP）：n（THF）：n（H₂O）=2：1：165：750，晶化温度100℃，晶化时间24h，150℃活化2h。合成Co-MOF-74对1-己烯和正己烷的静态饱和吸附量分别为125.6mg/g和72.9mg/g，BET比表面积为1209m²/g，孔体积为0.41cm³/g，微孔平均孔径为0.66nm。L-F吸附模型能较好地解释Co-MOF-74材料对1-己烯的吸附等温线数据，Co-MOF-74吸附1-己烯的过程是热力学自发放热过程。

关键词: 合成, 吸附, 烷烃, 分离

CLC Number:

TQ028

LIU Lu, REN Danni, LIU Jisan. Synthesis and the performance of Co-MOF-74 for n-hexane/1-hexene adsorption separation[J]. Chemical Industry and Engineering Progress, 2019, 38(s1): 179-185.

刘露, 任丹妮, 刘继三. Co-MOF-74的合成及其吸附正己烷/1-己烯性能[J]. 化工进展, 2019, 38(s1): 179-185.

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