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As a new type of porous material, the metal - organic framework complexes having the excellent characteristics of the conventional inorganic porous material incomparable, by changing the organic ligand can be regulated in a three-dimensional network in the pore size and pore properties can be achieved on different organic solvent molecules The selective adsorption. The pores of different structures and properties are different from the biasing force of the organic solvent having a different nature, resulting in the adsorbed amount is different, in order to achieve the selective adsorption, can be applied to the control and recovery of the organic waste gases that cause serious pollution of the environment. By solvothermal synthesis of three different structures of metal - organic frameworks complexes Zn (BDC) (4,4 '-Bipy) 0.5 (DMF) (H 2 O) 0.5 (MOF508; BDCs = 1,4-Benzenedicarboxylicacid-1, 4 pairs of terephthalic acid, 4,4 '-Bipy = 4,4'-bipyridine-4, 4 - bipyridine , DMF = dimethyl formamide-N, N-two methyl formamide), the Zn 3 (HTAA) 3 (H 2 O) < sub> 3 (C 4 H 8 O 2 ) (J370; Htaa = 2 - (5H-tetrazol-5- yl) acetic acid-four triazole acetic acid, C 4 H 8 O 2 = 1,4-dioxane-1, 4-dioxa ring), and Zn 4 (OH) 2 (1,2,4-BTC) 2 (H 2 O) the 2 (DEF) 3 (J372; 1,2,4-BTC1, 2,4-benzenetricarboxylic acid-1, 2,4 - benzene tricarboxylic acid; DEF = N, N-diethylformaide-N, N-diethylformamide), their structure and thermal stability by methods such as XRD, SEM, TGA, characterization, and study their adsorption of organic solvent molecules / desorption characteristics. In order to study the nature of the adsorbate on the adsorption / desorption performance, MOF508 adsorbent, choose a different chain lengths adsorbate (CH 3 OH C 2 H 5 OH the nC 3 H 7 OH), different structure adsorbate (nC 3 H 7 OH, iC 3 H 7 OH), the different size of the adsorbate (CH 2 Cl 2 , CHCl 3 , CCl 4 ) adsorption / desorption performance studies. The results show that the low pressure, long chain alcohols adsorption capacity in the short chain, while the short chain in the high-pressure adsorption capacity in the long chain; alcohol with a branched chain beginning not be adsorbed, adsorption amount of slow pressure rise increases; adsorbed adsorbate molecular size smaller volume, a large adsorption less in molecular size, and because a flexible framework complexes, individual molecular size greater than the pore size of adsorption. Further MOF508 on CS 2 adsorption exhibits a unique phenomenon in the process of adsorption curve slow adsorption platform described adsorption process shrink the intermediate state of a structure, when the pressure increase reaches a certain value , holes and re-open, continues adsorption, further illustrate the flexible qualities of MOF508 structure. Addition to select MOF508 as adsorbent, in order to study the impact of the framework of the structure and properties of the adsorption / desorption performance, selected with the different structures of the J370 and J372 for the study object, respectively, of different alcohols carried out the adsorption / desorption performance of the test . The results show that the frame was the size of the specific surface area and adsorption proportional relationship of the amount of the organic solvent molecules. Adsorption of alcohols in a large surface area, small pore size MOF508 generate capillary condensation; small specific surface area, small pore size J370 and large specific surface area, pore size of J372 does not produce such phenomena. Alcohol molecules with the hole wall MOF508 and J372 forces stronger, while J370 weaker. Found MOF508 effect the selective adsorption of the organic solvent molecules are more evident by the above studies. Reasonable choice of organic ligands, selective adsorption of MOFs can be designed on a specific organic solvent molecules is expected to be applied to the treatment of organic waste gas.
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