The Synthesis Of Four Interpenetration MOFs And The Application On Gas Chromatographic Separation Of Spices

Metal-Organic Frameworks?MOFs?as a new type of func tional material widely used in the gas storage,catalysis,separation,sensor and many other fields due to their unusual properties,such as high surface area,rich topologies,permanent microporous,availability of outer-surface modification and so on.Multiple interpenetration MOFs as important section of MOFs also have attracted much attention in asymmetric catalysis and separation because of the interpenetration enhance the structural stability,at the same time,has high thermal stability.At present,the interpenetration MOFs used as chromatographic stationary phase for separation is rare.In this paper,four interpenetrating MOFs have been synthesized and used for gas chromatographic?GC?separation of cinnamon,mint and other spices.First,We synthesized a new type of four-interpenetration frameworks [N i?pybz?2]·DMF?1?through the solvothermal method,it is a 4-interpenetration MOFs with diamond topology and a 1D channel size of 7.6 A ? 7.6 A in the c axis.Dynamic coating method was used to prepare capillary gas chromatography column,which succeefully separated six groups of spices including alcohol,aldehyde,ketone,acid,ester and ether in the GC.We also discuss the separation mechanism and simulate the van der Waals force between spices and this MOF.The experimental results show that stationary phase has good separation ability of the spices,and the simulation results accord with the results of chromatographic separation.Second,We synthesized two three-interpenetration frameworks [Zn?D.Cam??tmdpy?]·H₂O?2?and [Cd?D.Cam??tmdpy?]?3?through the hydrothermal method,and they have the same chiral diamond topology.It has a chiral ‘Z' chain,which bridge to a long flexible tmdpy ligand to form 3D structure and then self-assembled into 4-interpenetrated chiral MOFs.These two MOFs used as capillary GC column separated six groups of spices.The experimental results indicated that both the two MOFs can separation six groups of spices,but the separation ability of 3 is better than 2.Third,We synthesized a three-interpenetration frameworks [N i?D.Cam??tmdpy?]?4?through the hydrothermal method.It has the most unusual topological characteristics because the unique 4-connected double layer,which connected to the adjacent tmdpy ligand to form a 4-interpenetration 3D structures.Dynamic coating method was used to prepare capillary GC column,which successfully separated five groups of spices.The experimental results indicates that [N i?D.Cam??tmdpy?] used as capillary GC column can successfully separate five groups of spices,such as linner alkanes,aromatic compounds,and naphthene structure replaced by different functional groups?R-OH,H-C?R?=O,C?RR'?=O,HO-?R?C=O,R-O-?R'?C=O,R-O-R'?.