This study aims to analyze the effect of chemical pretreatment using sodium hydroxide (NaOH) onthe capacity of coco peat in removing of copper (11) ions from aqueous solutions. The effects ofvarying the molarity of NaOH, the solution pH, initial Cu(II) concentration, coco peat dosage andcontact time were studied in batch experiment. The result of the preliminary pretreatment studyshows that treatment with 0.5M NaOH greatly enhanced the metal sorption capacity of raw cocopeat. The uptake capacity for Cu of the raw coco peat was increased from 46% to 83% at pH 4.0and from 15% to 27% uptake for initial solution pH of 2.4. The results showed that the removalrate is directly proportional to pH, coco peat’s dosage and contact time and inversely proportionalto Cu(Il) concentration. The adsorption process is best explained by the Langmuir isotherm thanthe Freundlich isotherm, indicating monolayer adsorption on a homogenous surface. The rate ofreaction follows the pseudo-second order kinetic model, signifying that chemisorption is the ratelimiting mechanism. The results of the Fourier Transform Infra-Red (FTIR) analysis indicated thatthe main functional groups involved in the sorption of copper to NaOH pretreated coco peat are thehydroxyl, carboxyl and phenolic groups. Based on the results of this study, it was found thatpretreating coco peat with NaOH significantly improve the overall efficiency of coco peat inremoving Cu(II) by adsorption process. |