USE OF IRON-IMPREGNATED GRANULAR ACTIVATED CARBON FOR CO-ADSORPTIVE REMOVAL OF PHENOL AND CYANIDE: INSIGHT INTO EQUILIBRIUM AND KINETICS

In the present study, the effect of iron impregnation on granular activated carbon (GAC) for removal of multicomponents from synthetic wastewater was studied. It was observed that percentage removal of phenol and cyanide increased from 72.89% to 91.82% and from 75.99% to 95.57% respectively. A decrease in equilibrium time from 33 to 27h and a decrease in optimum adsorbent dose from 30 to 10g/L were also observed. Equilibrium modeling using two single-component isotherms and four multicomponent isotherms was performed, and it was found that extended Langmuir and extended Freundlich isotherm fits best to the adsorption of phenol and cyanide, respectively. Kinetic modeling using contact time studies was done to reveal the nature of adsorption and it was found that the rate-limiting step was a chemical adsorption process.