| Abstract: Intercalation of 1,2-,1,3-,1,4-benzenedicarboxylate or benzenecarboxylate ions into Zn,Al-HTlc was carried out by the reconstruction method in the molar ratio of organic acid: calcined HTlc=1∶9, in 80 % alcoholic aqueous solution at 70 ℃. Selective reaction was observed in competitive experiments involving an equal concentration pairs of acids. The structures of the intercalates formed by reaction of four guests with Zn, Al-HTlc were characterized by XRD and IR techniques. And the charge density on the oxygens of each of the carboxylate groups for each of the four anions was investigated utilizing ab initio (HF/6-31G) method by G98w. The orientation of 1,2-,1,3-,1,4-benzenedicarboxylate or benzenecarboxylate anions between the layers was also proposed. The results show that the preference order for intercalation of all guests in Zn,Al-HTlc was 1,4-benzenedicarboxylate > 1,2-benzenedicarboxylate > 1,3-benzenedicarboxylate > benzenecarboxylate. This material exhibits the preferential intercalativity for 1,4-benzenedicarboxylate from mixed pairs of organic acids and will be exploited as a method for the chemical separation of these anions from solution. |
