| Popis: |
Adsorption of gliclazide from aqueous solutions with carbon-based adsorbents is the aim of this study. For this purpose, magnetic, versatile, and inexpensive magnetic activated carbon (MAC) and magnetic multi-walled carbon nanotube (MMWCNT) adsorbents have been developed. MAC and MMWCNT characterization were analyzed using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Thermogravimetric analysis (TGA) techniques. In order to find the optimum conditions in batch adsorption experiments, the effects of parameters such as adsorbent dose, gliclazide solution pH, contact time, temperature and presence of foreign ions were investigated. Parameters were calculated for adsorption isotherms using Langmuir and Freundlich models. The adsorption studies of MAC and MMWCNT materials with gliclazide were in accordance with the nonlinear Langmuir and Freundlich isotherm models for all temperatures (298, 308, 318 K). The correlation coefficients of the Langmuir isotherm model are slightly higher than the Freundlich model. MAC adsorbent has maximum monolayer adsorption capacity at T=298 K (qmax=101.66 mg/g, R2=0.88) while MMWCNT has maximum monolayer adsorption capacity at T=308 K (qmax=71.59 mg/g, R2=0.90). For MAC and MMWCNT - Gliclazide adsorption systems, pseudo-first and secondorder kinetic models were examined and found to be more appropriate to the pseudo-secondorder kinetic model. The results showed that the MAC and MMWCNT could be could be promising adsorbents for gliclazide removal. |
