Performance of zinc removal by durian shell

Abstract

The durian shell is introduced as a new adsorbent for the removal of heavy metal from the aqueous solution. Various parameters, including pH (2-8), initial solution concentration (10-80 mg L-1), temperature (20-80 °C) and adsorbent dosage (0.01-0.08 g), were used to study the effects on durian shells biosorption. The results showed that the adsorption process took place well in alkaline condition with optimum pH 8. The adsorption rate decreased when the temperature increased. The adsorption is favoured with increase in adsorbent dosage and initial dye concentration. However the percentage of removal decreased once the amount of dosage reaches more than 0.6 g. The equilibrium data fitted better in Langmuir model, although it also can fit into Freundlich model demonstrating that the adsorption occurs at heterogeneous sites and multilayer biosorption. The maximum monolayer biosorption capacity was 78.71076 mg/g with the degree of adsorption 27.33 mg/g. The adsorption process followed the pseudosecond order kinetic model showing chemisorption was involved during adsorption process.