الفهرس | Only 14 pages are availabe for public view |
Abstract Thesis Title : Industrial Wastewater Treatment Using Modified Loofah and Corn Cobs axis as Low-Cost Adsorbents : Summary : In this study, activated carbons (CAC and LAC) and modified activated carbons (MCAC and MLAC) prepared from corn cobs and luffa sponge have been investigated for biosorption of Fe (III) from aqueous solution. Moreover, the residuals from iron adsorption onto prepared activated carbon (Fe-MCAC and Fe-MLAC) are reused as new adsorbents for ciprofloxacin (CIP) removal from pharmaceuticals wastewater. SEM, FTIR, XRD, Raman spectra, and N2 adsorption- desorption analysis have been used in adsorbents characterization. The effects of contact time, temperature, pH, adsorbent dosage, and initial pollutant concentration have been investigated by batch experiments. The adsorption mechanisms, performance, kinetics, isotherm, and thermodynamic for iron and CIP removal were evaluated. In addition, the reusability of residuals from iron adsorption were assessed for CIP removal. The results of iron removal have showed that the CAC and LAC were effective low-cost adsorbents for the removal of Fe (III) from aqueous solutions. In addition, the modification method significantly improving the adsorption property. The optimum pH is 8 for all adsorbents. The adsorption data fit well with Langmuir model for MCAC, Freundlich model for CAC and MLAC and Dubinin–Radushkevich model for LAC. The experimental data fitted very well by the pseudo-second-order model for all adsorbents (R2 = 0.999). The thermodynamic study confirmed the spontaneity and irreversibility of the adsorption process for all adsorbents. CAC and MCAC have exothermic nature, but LAC and MLAC have endothermic nature of the adsorption process. The results of CIP removal have showed that the isotherm data was well defined by Freundlich model for both adsorbents (residuals). Moreover, the adsorption kinetics followed the pseudo-second-order model. The maximum removal of CIP was obtained at pH 7 for both adsorbents. The optimum contact time was found to be 30 min and 60 min for Fe-MCAC and Fe-MLAC, respectively. The values of free energy change and enthalpy change for adsorption of CIP indicated the spontaneous, endothermic nature of the adsorption. In addition, the adsorption process was assisted by increasing randomness due to the value of entropy change. Therefore, the residuals from iron adsorption onto activated carbons could be reused as new low-cost adsorbents for antibiotics removal from wastewater. |