Kinetics and Thermodynamic Studies: Adsorption of Pb, Cr and Ni Ions from Spent Lubrication Oil (SLO) Using Acid Modified Clay

Abstract

Adsorption of Pb, Cr, and Ni ions from spent lubrication oil (SLO) by sul-phuric acid modified clay (SAMC) was investigated considering the effect of contact time and temperature of the adsorption system. The removal percen-tage of the heavy metals was found to be temperature and contact time- dependent. Adsorption of the heavy metals increases with an increase in temperature and contact time with 95.0% - 100% adsorption recorded at the temperature of 331 K with the equilibration time of 12 hours. The thermody-namic and kinetics investigation of the adsorption process showed that the adsorption of these metals by the modified adsorbent is a spontaneous and endothermic physical adsorption process that followed the pseudo-second- order kinetic model.