BITE 120-2012-218

Utilization of bivalve shell-treated Zea mays L. (maize) husk leaf as a low-cost
biosorbent for enhanced adsorption of malachite green

In this work, two low-cost wastes, bivalve shell (BS) and Zea mays L. husk leaf (ZHL), were investigated to
adsorb malachite green (MG) from aqueous solutions. The ZHL was treated with calcined BS to give the
BS-ZHL, and its ability to adsorb MG was compared with untreated ZHL, calcined BS and Ca(OH)2-treated
ZHL under several different conditions: pH (2–8), adsorbent dosage (0.25–2.5 g L1), contact time
(10–30 min), initial MG concentration (10–200 mg L1) and temperature (303–323 K). The equilibrium
studies indicated that the experimental data were in agreement with the Langmuir isotherm model.
The use of 2.5 g L1 BS-ZHL resulted in the nearly complete removal of 200 mg L1 of MG with a
maximum adsorption capacity of 81.5 mg g1 after 30 min of contact time at pH 6 and 323 K. The results
indicated that the BS-ZHL can be used to effectively remove MG from aqueous media.