Original Articles
Meilia Innes Kurniawan, Edison
Abstract
Dimocarpus longan peels, the low-cost adsorbent, was investigated of removing Pb(II) and Cu(II) ions from aqueous solutions. Batch adsorption studies were conducted to examine their optimum conditions. For adsorption of Pb(II), the optimum pH solution, contact time and stirring speed were 5.0, 90 min and 200 rpm, respectively. Those values for Cu(II) ions were 4.0, 90 min and 100 rpm, respectively. Based on the correlation of determination (R), several kinetic models were able to describe the equilibrium contact time data in the order : 2nd > 1st > Intraparticle > Elovich. Data obtained from variation of initial concentrations were found to fit the Langmuir, Freundlich, D-R and Temkin adsorption isotherms with R of D-R ≈ Freundlich > Temkin > Langmuir. The maximum capacity for Cu(II) ions was 8.2175 mg/g. Meanwhile, Pb(II) ions fit the Linear adsorption isotherm, so that no maximum capacity to be found.