苯酚在多孔金属有机框架材料中吸附扩散的分子模拟

Adsorption and Diffusion of Phenol in Porous Metal-Organic Frameworks

苯酚因其高毒性和难生物降解性被列为优先处理污染物,对其有效去除十分重要。本文采用分子模拟方法探索两种多孔有机金属框架材料(Metal organic frameworks,MOFs)对苯酚的吸附扩散机理。研究结果表明,Cu-BTC对低浓度苯酚溶液具有良好吸附效果,在浓度约为200 mg·L^(-1)时达到吸附饱和,饱和容量为80 mg·g^(-1);而MIL-53(Al)则在浓度超过500mg·L^(-1)时对苯酚大量吸附,饱和吸附量达到450 mg·g^(-1)。为深入理解MOF对苯酚的吸附过程,对其扩散现象进一步研究,并确定了氢键和π-π堆积作用是苯酚吸附的主要作用力。该研究从分子层面上获得了多孔MOF材料对苯酚吸附的微观机制,并且表明Cu-BTC和MIL-53(Al)对酚类污染物吸附处理具有广阔的应用前景。

Phenol is considered as a priority pollutant in environment due to its high toxicity and hard to biodegradation,thus its effective removal is very important.We here report a molecular simulation study to probe the adsorption and diffusion mechanisms of phenol in two metal-organic frameworks(MOFs)Cu-BTC and MIL-53(Al).The results indicate that Cu-BTC has excellent adsorption ability to low concentration of phenol solution.It reaches the saturation adsorption at concentration of 200 mg·L^(-1) and adsorption capacity is 80 mg·L^(-1);MIL-53(Al)adsorbs a large amount phenol at the concentration exceeds 500 mg·L^(-1) and its adsorption capacity is 450 mg·L^(-1).To well understand the adsorption process of phenol,the diffusion behavior was further investigated that the hydrogen bond andπ−πstacking interactions are the main adsorption forces.This study not only provides fundamental insight into the microscopic properties on the adsorption of phenol by nanomaterials,but shows that Cu-BTC and MIL-53(Al)have potential applications in the removal of phenol pollutants.