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为明确纳米碳对重金属的吸附性能,在液/液吸附体系下研究了纳米碳对镉和铜的吸附特征,并探讨了土培条件下对土壤有效态镉含量(质量分数)及烟草吸收镉的影响。结果表明,纳米碳对镉和铜的等温吸附曲线可以用Freundlich和Langmuir方程较好地拟合。纳米碳对镉和铜的吸附符合准二级动力学方程,且吸附速度较快。当溶液的初始浓度为2 000 mg/L,10 min时镉的吸附量可达到平衡吸附量的80%以上;而铜相对较快,3 min即可达到平衡吸附量的80%。随着温度的升高,纳米碳对镉和铜的吸附量降低,表明纳米碳的吸附是放热反应;随着p H值的增加,其吸附量增大。该试验条件下,随着纳米碳用量的增加,土壤有效态镉含量及烟叶中镉含量均降低。当纳米碳用量为4.0 g/盆时,效果最好。
In order to clarify the adsorption properties of nano-carbon to heavy metals, the adsorption characteristics of nano-carbon to cadmium and copper were studied under the liquid / liquid adsorption system. The effects of soil nano-carbon on the available cadmium (mass fraction) Impact. The results show that the adsorption isotherms of Cd and Cd by carbon nanowires can be well fitted by the Freundlich and Langmuir equations. Nanocarbon adsorption of cadmium and copper in line with quasi-second-order kinetic equation, and the adsorption speed. When the initial concentration of the solution is 2 000 mg / L, the amount of cadmium adsorbed can reach more than 80% of the equilibrium adsorption amount at 10 min; while the copper is relatively fast, reaching 80% of the equilibrium adsorption amount in 3 min. With the increase of temperature, the adsorption amount of nano-carbon to cadmium and copper decreased, indicating that the adsorption of nano-carbon was exothermic reaction; with the increase of p H, the adsorption increased. Under the experimental conditions, with the increase of the amount of nano-carbon, the available cadmium content in soil and cadmium content in tobacco leaves decreased. When the amount of nano-carbon 4.0 g / pot, the best.