磁响应酵母对直接黄R染料的吸附动力学研究

采用水相合成的纳米级铁磁流体对灭活酿酒酵母细胞进行磁修饰。将具有良好磁响应的酵母用于吸附直接黄R染料。结果表明：在染料质量浓度为600μg/mL时，磁修饰酵母对该染料的吸附率为92.6165%，吸附量为1109.5122μg/mg，20min达到吸附平衡；吸附方式用Langmuir吸附等温线拟合较好（R2=0.9991），属于单分子层吸附，符合二级表观动力学方程，吸附过程主要由化学机理控制。由于磁修饰酵母比同质量下单独的酵母和铁磁流体吸附容量大，吸附速率快，易于磁分离，在水溶性染料废水的处理上具有应用潜力，有助于减轻其对土壤和水体环境的污染。

Absorption kinetics of Direct Yellow R on magnetically responsive yeast cells

The nano-sized magnetic fluid in aqueous phase solution was prepared to modify the inactivated yeast cells. The modified yeast cells with good magnetic response were used to adsorb Direct Yellow R. The results showed that the adsorption capacity of modified yeast cells reached 1109.5122 μg/mg of Direct Yellow R at the concentration of 600 μg/mL, and adsorption equilibrium was achieved within 20 min. The adsorption equation was well fitted using Langmuir isothermal line, belonging to single molecular layer adsorption and conforming to the pseudo-second-order apparent kinetics equation. The adsorptive process was controlled by chemical mechanism. Because of the strong adsorption capacity, high adsorption speed and easy magnetic separation of the magnetically modified yeast cells as compared with yeast or magnetic fluid alone, their potential applications include treatment of waste water resulting from water-soluble dyes, helping reduce the pollution to the soil and water.