Preparation of metal-organic framework based carbon materials and its application to adsorptive removal of cefepime from aqueous solution

Metal-organic framework based carbon material UC-X was prepared by template method, and adopted to remove cephalosporins from aqueous solution. The effect of templates including cetyltrimethyl ammonium bromide and sodium laurate was discussed. The UC-0.1 with the pore size of 5.38 nm has the best adsorption. According to FTIR spectrum, with the gradual increase of sodium laurate, the functional groups like C=O increased, which promoted the adsorption capacity of cefepime in UC-X materials from 42.52 to 84.23 mg.g(-1). The optimal conditions for the adsorption of cefepime were determined by the response surface method: the adsorption temperature was 25.8 degrees C, the initial pH value was 6.11, and the ionic strength was 1.13 g.L-1. Under the best adsorption condition, the adsorption-desorption experiments showed that the adsorption capacity of UC-0.1 material decreased by less than 10 % after five times usage, which indicated that its recycling property was competitive. The adsorption process conformed to the mixed-order kinetic model, and the error of equilibrium adsorption capacity between model fitting and actual experiments is not more than 1 %. The overall results of adsorption isotherm model and thermodynamic analysis demonstrated that Redlich-Peterson isothermal model could describe the adsorption process better.