| In this work the ability of some plant materials, as potentially new sorbents, to sorb heavy metals from aqueous solutions was investigated. In addition, a new microbial sorbent, that has not been tested before for the sorption of heavy metals, was also considered.;The microorganism Aspergillus carbonarius and the following plant materials were found to be able to sorb copper ions from aqueous solutions: canola meal (CM), pine bark, pine needles, pine cones, moss, oak leaves, oak cobs, maple leaves, birch leaves and cider needles. Of these sorbents A. carbonarius, CM, pine bark and moss were considered more extensively in this work.;The kinetics of metal uptake by A. carbonarius, CM, bark and moss were studied.;Sorption studies using A. carbonarius showed that pre-heating of this biomass to higher temperatures prior to utilizing it in the biosorption tests decreased its metal sorption capacity. The affinity of A. carbonarius for different metal ions followed the order (molar basis): Cu;The ability of moss to adsorb various metal ions was examined in a batch sorption process. The affinity of this sorbent toward heavy metals was (molar basis): Cr;The performance of moss for metal sorption was also examined in a continuous process using a column packed with this sorbent. Increases in the flow rate or the influent metal concentration resulted in shorter break-through times and higher copper uptakes per unit mass of moss.;Pine bark can be used for the sorption of the following metals from aqueous solutions with the following order of capacities (molar basis): Cu;The performance of CM, bark and moss for the removal of copper from industrial wastewater was tested. The copper concentration in the wastewater was decreased from 36.5 to 2.5, 4.1 and 5.2 ppm by bark, moss and CM, respectively, when the sorbents concentrations were 18.4 mg/mL.;Single, binary, ternary and quaternary metal systems of Cu;The global compositional analysis showed that lignin and carbohydrates for bark and moss, and proteins, carbohydtates and phytic acid for CM, are the major components responsible for the sorption of heavy metals. The roles of the carboxyl and amine groups in the sorption process were also examined. (Abstract shortened by UMI.). |
