Coconut dregs, soya dregs and lala clam shells have been used as low cost sorbents for the removal of heavy metals from aqueous solution. The effect of pH, contact time, initial metal concentration and temperature on sorption process was studied in batch experiments. Results of the equilibrium experiments showed that the solution pH was the key factor affecting the sorption characteristics. The kinetics data were best described by pseudo-second order, while the equilibrium data were best fitted by Langmuir isotherm. The thermodynamic studies indicated that the sorption is spontaneous and endothermic. Desorption studies showed that heavy metals are retained on the sorbents' surface following interaction with eluents. FTIR analysis confirmed that 0- and N-containing functional groups are the main sorption sites in coconut dregs and soya dregs. The presence of calcium carbonate in lala clam shells favours ion exchange mechanism. Based on effectiveness study using industrial wastewater, it.....

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