Preparation of copper based metal organic framework materials and its effective adsorptive removal of ceftazidime from aqueous solutions

In view of the great complexation between Copper(II) and cephalosporins, and excellent ability of coordination of 1,3,5-Benzenetricarboxylic acid, the mesoporous copper based metal organic framework material CS-X was synthesized and utilized to remove ceftazidime from aqueous solutions. Templates were used to adjust the pore sizes of CS-X and the characterization results indicated that the addition of templates did not change the crystalline structure. The optimum CS-0.2 material with the best adsorption capacity had the pore size of 3.90 nm. The XPS spectra showed that the hydrogen bonds were formed between the -NH2 groups of ceftazidime and the adsorbent, which accelerated the adsorption efficiency. The effect of ionic strength, pH and humic acid on adsorption was studied. The kinetics of ceftazidime adsorption on CS-0.2 demonstrated that the adsorption reached equilibrium in the first 20 min and corresponded to the pseudo-second-order model. The adsorption mechanism suggested that the adsorption of ceftazidime on CS-0.2 is spontaneous and endothermic, predominating by the chemical adsorption, in good conformity with the Langmuir and Temkin isotherm models. Besides, the studies showed that the CS-0.2 had a high efficiency and selectivity for the removal of the numerous cephalosporins from aqueous solutions.