Abstract

The adsorption of Lead onto apricot stone activated carbon (ASAC) in a batch adsorber has been studied. The adsorbent was characterized by FTIR, BET, X-fluorescence, X-ray diffraction and SEM. The effects of contact time, initial pH, agitation speed, adsorbent dosage and initial dye concentration on the Lead adsorption by the ASAC have been studied. Lead removal was seen to increase with increasing contact time until equilibrium and initial dye concentration, and the adsorption capacity of ASAC selected to follow the adsorption process. Batch adsorption experiments were first undertaken to assess the effect of various parameters on the removal efficiency of Lead. It was observed that under optimized conditions up to 166.813mg/g at 25 oC at pH 8 could be removed from solution. Kinetic parameters; rate constants, equilibrium adsorption capacities and correlation coefficients, for each kinetic equation were calculated and discussed. It was shown that the adsorption of Lead onto ASAC could be described by the pseudo second-order equation. The experimental isotherm data were analyzed using the Langmuir, Freundlich and Temkin equations. Adsorption of Lead onto ASAC followed the Freundlich isotherm. The evaluation of thermodynamics parameters indicated respectively the spontaneous and endothermic nature of the reaction and the chimisorption of the sorption process.

Keywords: Apricot stone; Heavy metal; Isotherm; Removal; Thermodynamic