An experimental design methodology was applied to study the copper removal from aqueous solutions by immobilized nanoscale
Lentinus edodes. The effect of the various variables (biomass loading, initial metal ions concentration, PH, contact time, agitation
speed and temperature) were studied in the batch experiment. The results showed that pH, contact time and agitation speed were
the most significant variables on biosorption of copper ions determined by Minimum Run Equireplicated Res V Design. Then
Central Composite Design was employed to optimize the process conditions for the maximum removal of copper. A maximum
copper removal (97.57%) was found to occur under pH of 6 and contact time of 540 min and agitation speed of 125 rpm. The
kinetic data agreed well with the pseudo-second-order model and the equilibrium sorption data followed the Freundlich model.
Scanning electron microscope (SEM) and energy dispersive spectrometry (EDS) analysis confirmed the apparent change of the
surface morphology and the existence of copper ions on the biosorbent after metal binding. The biosorbent could be regenerated
by 1M HNO3 with only 8.66% decrease in adsorption capacity and the desorption of the biosorbent was of high percentage after
three adsorption-desorption cycles. The present work suggests that immobilized nanoscale Lentinus edodes, an abundant low-cost
biomaterial, was an efficient biosorbent for copper removal from wastewater.