改性棉秆吸附Cr(Ⅵ)工艺研究

以棉花秸秆为原料,在超声波作用下用二硫化碳进行化学改性,制得改性棉秆吸附剂。通过正交试验确定了各因素影响次序和最佳工艺水平组合。结果表明:在pH=1.61、吸附时间为138.47min、吸附剂用量为0.27g、温度为51.61℃条件下,最高吸附效率为99.99%,其中pH在影响改性棉秆吸附过程中表现最为敏感,温度其次;准二级动力学方程拟合效果最好,吸附过程为放热自发反应。利用扫描电子显微镜对改性前后棉秆进行分析,证明改性方法有利于吸附的进行。

Adsorption process of Cr(Ⅵ) on modified cotton stalk

Cotton straw was used as a raw material,and used carbon disulfide for chemical modification under the action of ultrasound to obtain a modified cotton straw adsorbent.The order of influencing factors and the optimum technological level were determined by orthogonal test.The results shown that the highest efficiency of 99.99% was obtained at pH 1.61,adsorption time 138.47 min,adsorbent amount 0.27 g,temperature 51.61℃.The pH was the most sensitive factor followed by temperature.The pseudo secondary dynamics had better fitting effect,and adsorption process was spontaneous reaction heat release.Before and after the modification,the cotton stalk was analyzed by electron microscope,it was proved that the modification method was favorable for the adsorption.