热处理平菇对低浓度铀吸附性能的研究

Adsorption of Low Concentration U(Ⅵ) Using Pleurotus Ostreatus by Heat Treatment

以热处理平菇子实体作为生物吸附剂,研究其对低浓度铀的吸附性能,采用批试验考察pH、温度、时间和平菇加入量对吸附性能的影响,对动力学、热力学和等温吸附模型进行了拟合。结果表明,当溶液pH为5.0,温度为35℃时,吸附效果最好,并在3 h趋于平衡。初始铀浓度为1 mg/L,热处理平菇对铀的平衡吸附量和吸附率分别为4.53 mg/g和90.5%。等温吸附方程参数说明热处理平菇对铀离子具有较大的吸附潜力;准二级动力学模型能较好地描述其动力学特性;吸附反应是自发的,且为吸热反应,适当地升温可以促进平菇对铀的吸附。

The adsorption properties of U（VI） on heat treated pleurotus ostreatus were investigated. The effects of pH, contact time, sorbent dosage and temperature on the adsorption capacity were studied. The heat treated biomass exhibited the adsorption efficiency of 90.5 % and the adsorption capacity of 4.53 mg/g for uranium under the optimum conditions that pH was 5.0, the contact time was 3 h, the temperature was 35 ℃ and the initial uranium concentration was 1 mg/L. The adsorption equilibrium data showed pleurotus ostreatus had potential as adsorbent in removal and recovery of U（VI） from large volumes of aqueous solutions. The pseudo-second order model was well fitted. The thermodynamic data indicated that the adsorption process of U（VI） was spontaneous, feasible and endothermic. Accordingly, adequate raise of temperature was helpful for adsorption.