Thermodynamic and breakthrough column studies for the selective sorption of chromium from industrial effluent on activated eucalyptus bark

Studies were carried out on adsorption of Cr(VI) on an adsorbent made from eucalyptus bark. Results revealed that sorption of chromium on activated eucalyptus bark (AEB) was endothermic in nature. Thermodynamic parameters such as the entropy change, enthalpy change and Gibb’s free energy change were found out to be 100.97 J mol−1 K−1, 33 kJ mol−1 and −0.737 kJ mol−1, respectively. Industrial chrome effluent of different chromium concentration at different pH was used as feedstock for the fixed bed adsorption studies. When effluent was fed to the column at low pH of 2, the breakthrough volume increased significantly compared to effluent at higher pH of 4.85. The surface properties of sorbent were characterized by the Scanning electron microscopy, X-ray diffraction technique and Infrared techniques. It was concluded that AEB sorbent column could be used effectively for removal of chromium from industrial effluents by reducing the pH of chrome effluent to two and at optimal column conditions.