Biosorptive removal of Hg(II) ions by Rhizopus oligosporus produced from corn-processing wastewater

摘要

In this study, corn processing wastewater was used as a new low-cost substrate to produce?Rhizopus oligosporus. Dried biomass of?R. oligosporus?was evaluated as a biosorbent for treatment of synthetically contaminated waters with Hg(II) ions. The biosorption process was carried out in a batch process and the effects of contact time (1 to 48 h), initial pH (2.0 to 7.0), initial metal ion concentration (20 to 100 mg/L) and temperature (20 to 38°C) on the biosorption were investigated. Hg(II) ions concentration were measured with ICP-MS. The maximum?adsorption capacity?was determined at pH?6.0.?The isothermal data of dried fungal biomass could be described well by the Langmuir equations and the Langmuir monolayer capacity had a mean value of 33.33 mg/g. Experimental results indicated that the pseudo-second order reaction model provided the best description of the data with a correlation coefficient 0.99 for different initial metal concentrations. This result indicates that?chemical sorption might be the basic mechanism in this system.