Chadrudee Sirilamduan, Songsak Sakaew, and Pairat Kaewsarn

pp. 725 - 732

Abstract

The removal of Cu²⁺ ions by adsorption using biomass derived from Zalacca edulis peel was studied in a batch system.
The effects of pH and chemical pre-treatment of the biomass by the use of CaCl₂
 with different thermal conditions and initial
concentrations were also determined. The results showed that chemical pre-treatment by CaCl₂
 enhanced the capacity of Cu²⁺
ions biosorption. The equilibrium sorption data of untreated Zalacca edulis peel and Zalacca edulis peel pre-treated with

CaCl₂
 were fitted well by both Langmuir and Freundlich isotherms equations. According to the Langmuir equation, the maximum uptake of Cu²⁺ ions by the use of Zalacca edulis peel pre-treated with CaCl₂
 was found to be 27.03 mg g^-1 at pH 5. The
rate of adsorption was found to conform to pseudo-second order kinetics with good correlation. The binding between heavy
metal Cu²⁺ ions and chemically pre-treated biosorbent was confirmed by the use of scanning electron microscope combined
with energy dispersive X-ray analysis and electron probe microanalyser.