Equilibriumand kinetics studies on the removal of Cd (II) fromaqueous solution using hydrochloric acid and sodiumhydroxide treated cow hoovesAuthor(s): Ilesanmi Osasona, Albert O.Adebayo, Afemefuna E.Okoronkwo, Olubode O.Ajayi
The influence of operation parameters on the removal cadmium ions from aqueous solutions using hydrochloric acid treated (HCH) and sodium hydroxide treated (SCH) cowhooveswas investigated. The results obtained showed that pH of 3 and 6, and agitation time of 30 and 60 minutes were sufficient for maximum removal of cadmium by SCH and HCH respectively. The kinetic modeling of the adsorption data was best described by pseudo-second order kinetic equation. Three non-linear isotherm models were used to analysed the data obtained at four different temperatures of 25, 35, 45 and 55 C. The data obtained for both HCH and SCH were best described, based on the R2 and error function values by Langmuir model at all temperatures considered except the data obtained for HCH at 35 C which was best described by Freundlich model. The maximum adsorption capacities recorded for SCH (7.19-7.92 mgg-1) were higher than those recorded for HCH (2.84-5.51 mgg-1). The information on the FTIR spectra of the biosorbents coupled with those on adsorption energy showed that both chemical adsorption and physical adsorption were involved in the removal of Cd (II) from aqueous solutions.