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目的合成功能材料NTA-MCM-41并研究其对农药恶霉灵的吸附性能。方法采用两步嫁接法先后用3-氨基三甲氧基硅烷和氨基三乙酸对纯硅源的MCMC-41介孔分子筛进行功能化修饰得到新型材料NTA-MCM-41,利用正交试验方法找到其对恶霉灵吸附的最优条件。对其等温吸附曲线以及动力学数据进行拟合确定其热力学吸附方式和动力学吸附形式。通过对比实验比较功能化材料与非功能化材料的好处。结果研究结果表明,功能化后的材料对恶霉灵的吸附有明显的提高,恶霉灵的最优吸附条件为初始浓度5 mg/m L,吸附温度70℃,吸附时间9 h。功能化材料吸附恶霉灵的等温吸附曲线符合弗莱特利希(Freundlich)模型,吸附动力学符合一级反应方程。作为吸附剂的再生能力也非常好。经过五次循环吸附后,对恶霉灵的去除率仍然达到50%以上。结论氨基三乙酸的成功嫁接使介孔材料在吸附性方面有很大提高,在食品安全检测方面有很好的应用前景。
Objective To synthesize functional material NTA-MCM-41 and study its adsorption on pesticide hymexazol. Methods The new material NTA-MCM-41 was obtained by functional modification of MCMC-41 mesoporous molecular sieve with 3-aminotrimethoxysilane and 3-aminotriacetic acid using two-step grafting method. The orthogonal experiment was used to find out The best conditions for hymexazol adsorption. The isothermal adsorption curves and kinetic data were fitted to determine the thermodynamic and kinetic adsorption patterns. Compare the benefits of functional and non-functional materials by comparing experiments. Results The results showed that the adsorption of hymexazol on the functionalized materials was improved obviously. The optimum adsorption conditions for hymexazol were 5 mg / ml, initial temperature 70 ℃, and adsorption time 9 h. The isothermal adsorption curves of functional materials adsorbed hymexazol conformed to the Freundlich model and the adsorption kinetics fit the first-order reaction equation. Regeneration as an adsorbent is also very good. After five cycles of adsorption, the removal of hymexazol is still above 50%. Conclusion The successful grafting of aminotriacetic acid has greatly improved the adsorptivity of mesoporous materials and has good application prospects in food safety testing.