Removal of diclofenac and oxytetracycline from synthetic urine by furfuryl alcohol-derived mesoporous carbon

In this study, using furfuryl alcohol as the precursor carbon and mesoporous silica as the template, and furfuryl alcohol-derived mesoporous carbon (FMC) was prepared. The specific surface area of FMC was 1022.61 m2/g, the pore volume was 1.71 cm3/g, and the mesoporous volume was 98.8%. Based on the adsorption kinetics of pharmaceuticals onto the FMC in synthetic urine, equilibrium adsorption was reached in 120 min, and it followed a pseudo-second-order model. The adsorption isotherms were well-fitted by the Sips isotherm model, and the saturated adsorption capacities of diclofenac and oxytetracycline in fresh urine were 411.8 mg/g and 465.9 mg/g, respectively. Batch experiment results showed that pharmaceutical removal was strongly influenced by urine components such as sodium chloride, urea, and ammonium hydroxide. The adsorption of diclofenac and oxytetracycline was influenced by many factors including π-π interactions, hydrogen bonds, and electrostatic forces. FMC exhibited excellent reusability and retained urine nutrients during pharmaceutical adsorption.