【摘要】 为了研究蒙脱石对水体中恩诺沙星的吸附性能,采用XRD、FTIR、SEM、BET等对蒙脱石进行表征,并用于对水体中恩诺沙星的吸附。结果表明,蒙脱石为钙钠基蒙脱石,比表面积较大; pH值、吸附时间、初始恩诺沙星质量浓度对蒙脱石吸附恩诺沙星影响较大。当pH=6时,蒙脱石对恩诺沙星的去除效果最佳。等温吸附曲线拟合中,Langmuir模型拟合效果较好,表明恩诺沙星在蒙脱石表面的吸附为单分子层吸附。动力学拟合结果表明,准二级动力学模型很好地描述了蒙脱石对恩诺沙星的吸附行为及吸附过程。因此,蒙脱石是一种高效吸附恩诺沙星的吸附剂,可用于喹诺酮类抗生素污染水体的修复和治理。更多还原

【Abstract】 The present paper is inclined to study the adsorptive property of montmorillonite to enrofloxacin in the ordinary water.For this purpose,we have first of all examined the properties of the montmorillonite systematically though various technical means,such as XRD,FT-IR,SEM,and BET. And,then,theadsorption experiments have been done to examine and test the adsorption capacity of the enrofloxacin to montmorillonite from the aqueous solution. The results of our above discussion would like to show that the montmorillonite belongs to the Ca-Na-montmorillonite,which is rough enough with a large area surface.Seeing the above situation,we have done a thorough investigation over the adsorption capacity of the montmorillonite in terms of the effects of the initial pH value,the contact time,and the initial enrofloxacin concentration. For all the above mentioned items,like the pH value,the adsorption time,and the initial enrofloxacin content tend to have great impact on the adsorption for the montmorillonite of enrofloxacin. Therefore,the results of our investigation help to demonstrate that the adsorption process of enrofloxacin should heavily depend on the pH value of the solution.In addition,the uptake percentage of the enrofloxacin adsorption can also be abruptly increased if the pH value of the solution can increase from 2. 0 to 6. 0. And,then,when the pH value has increased to over 6. 0,it would be possible to notice a gradual decrease from the uptake percentage rate. Moreover,the montmorillonite adsorption capacity for the enrofloxacin can also be made to the highest rate when pH = 6. And,then,the montmorillonite adsorption isotherm of the enrofloxacin has thus been found in accordance with the Langmuir model. This may indicate that the adsorption belongs to the monolayer nature,whose maximum adsorption capacity should be equal to 115. 75 mg/g,that is,much higher than those of the other adsorbents reported. And,what is also necessary to mention is that,of the mathematical models suitable for describing the adsorption kinetics,the pseudo-second-order model should be taken as the best and the needed one.And,its correlation coefficient R~2 has turned out to be 0. 999,and that is higher than that of pseudo-first-order model( R~2=0. 948). Furthermore,the calculated equilibrium adsorption capacity of the enrofloxacin can also be worked out in accordance with the pseudo-second-order kinetic model,much closer to the experimental value. Therefore,the adsorption process can better be made to be denoted by the pseudo-second order model,signifying that the adsorption mechanism belongs to the chemical adsorptive one. And,so,the montmorillonite here under discussion can be regarded as a kind of highly efficient and promising adsorbent,which can be adopted to reduce the fluoroquinolone antibiotic in water.更多还原