Adsorption kinetics and mechanisms of ni2+ sorption using carbonized and modified sorghum (Sorghum bicolor) hull of two pore sizes (150 µm and 250 µm): A comparative study

Abstract

Aim of this study was to investigate the use of modified and carbonized Sorghum Hull of two different pore sizes in the removal of Nickel (II) ion from aqueous solution. The effect of contact time was investigated and reported. The maximum adsorption for 150 μm and 250 μm were at the 80th minutes respectively (38.354 mg/l and 38.173 mg/l). Both pore sizes showed peak adsorption of Ni2+ at a same adsorption time. Kinetic modelling of the results of Ni2+ of both pore sizes were also investigated. These results showed that Pseudo second order kinetic model best describes the process and the Mechanism of adsorption show that film diffusion controlled was 150μm and intraparticle diffusion control was 250 μm. This will serve as parameters to consider in the design of treatment plants for heavy metal detoxification using biosorbents of different pore sizes.