Adsorptive removal of vitamin B6 and ciprofloxacin using polyurethane foam in pure and pharmaceutical preparations: Kinetic and equilibrium studies

The release of active pharmaceutical ingredients and their metabolites in surface waters and groundwater with insufficiently treated wastewaters nowadays may be a global environmental concern. In this study, simple, inexpensive, and solid phase procedure has been developed for the removal of pyridoxine hydrochloride (vitamin B6, PDX) and ciprofloxacin (CPX) onto polyurethane foam (PUF) using the batch mode technique. PUF was characterized using scanning electron microscopy and FT‐IR spectroscopy. The batch experiments indicated optimum conditions for the adsorption process at pH 5.6 for PDX and CPX. The optimum contact time to reach its best removal is 30 min for the removal of both drugs and the sorbent amount at 1.0 and 1.5 g for PDX and CPX, respectively. It was found that the experimental data for the adsorption of PDX fit well into Langmuir model with R2 values (0.979). Whereas the adsorption of CPX follows Freundlich model with R2 value (0.914). Adsorption process undergoes pseudo‐first‐order kinetic as proved by the high value of R2 (0.973) and (0.956) for PDX and CPX, respectively. Experimental results have proven that PUF has a great potential for the removal of both drugs with maximum removal efficiency 50 and 98% for PDX and CPX, respectively. Removal of vitamin B6 and ciprofloxacin by adsorption onto polyurethane foam was studied and different conditions were evaluated. The optimum conditions were found to be pH 5.6, contact time 30 min for both drugs and the sorbent amount at 1.0 g, 1.5 g for PDX and CPX, respectively. Maximum removal efficiencies were 50 and 98% for pyridoxine hydrochloride and ciprofloxacin, respectively.