Sari Ahmet, Tuzen Mustafa
Department of Chemistry, Gaziosmanpasa University, Tokat, Turkey.
J Hazard Mater. 2009 May 30;164(2-3):1372-8. doi: 10.1016/j.jhazmat.2008.09.047. Epub 2008 Sep 21.
The biosorption characteristics of As(III) and As(V) from aqueous solution using the macrofungus (Inonotus hispidus) biomass were investigated as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the metal ions by I. hispidus biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The biosorption capacity of I. hispidus for As(III) and As(V) was found to be 51.9 mg/g and 59.6 mg/g, respectively at optimum conditions of pH 6 for As(III) and pH 2 for As(V), contact time of 30 min and temperature of 20 degrees C. The metal ions were desorbed from I. hispidus using both 1M HCl and 1M HNO(3). The high stability of I. hispidus permitted 10 times of adsorption-elution process along the studies with a decrease about 11-28% in recovery of As(III) and 10-25% for As(V). The mean free energy values evaluated from the D-R model indicated that the biosorption of As(III) and As(V) onto I. hispidus biomass was taken place by chemical ion-exchange. The calculated thermodynamic parameters showed that the biosorption of As(III) and As(V) ions onto I. hispidus biomass was feasible, spontaneous and exothermic under examined conditions. Kinetic examination of the experimental data were showed that the biosorption processes of both As(III) and As(V) followed well pseudo-second-order kinetics.
研究了使用大型真菌（糙皮侧耳）生物质从水溶液中吸附As(III)和As(V)的特性，考察了pH、生物质用量、接触时间和温度的影响。应用Langmuir、Freundlich和Dubinin-Radushkevich（D-R）模型描述糙皮侧耳生物质对金属离子的生物吸附等温线。Langmuir模型比Freundlich等温线更能拟合平衡数据。在As(III)的最佳pH为6、As(V)的最佳pH为2（接触时间30分钟、温度20℃）的条件下，糙皮侧耳对As(III)和As(V)的生物吸附容量分别为51.9 mg/g和59.6 mg/g。使用1M HCl和1M HNO₃从糙皮侧耳中解吸金属离子。糙皮侧耳的高稳定性使得在研究过程中可以进行10次吸附-洗脱过程，As(III)的回收率下降约11-28%，As(V)的回收率下降10-25%。根据D-R模型评估的平均自由能值表明，As(III)和As(V)在糙皮侧耳生物质上的生物吸附是通过化学离子交换进行的。计算得到的热力学参数表明，在考察条件下，As(III)和As(V)离子在糙皮侧耳生物质上的生物吸附是可行的、自发的且放热的。对实验数据的动力学研究表明，As(III)和As(V)的生物吸附过程均符合良好的准二级动力学。
