活性白土/壳聚糖复合物对多成分金属离子的吸附性能研究

摘要

以活性白土、壳聚糖为原料,通过表面活性剂十六烷基三甲基溴化铵对活性白土进行化学改性,将改性后的活性白土与壳聚糖复合制备得目标产物—活性白土/壳聚糖复合物.通过红外光谱(IR)、热重(TG)、X-射线衍射(XRD)和透射电子显微镜(TEM)对所制得的复合物进行表征,探究复合物的结构、热稳定性能和形貌.十六烷基三甲基溴化铵(CTAB)改性后的活性白土的片层间距由1.831 nm增长到2.299 nm;通过单因素变量法研究活性白土与壳聚糖的适宜配比、吸附剂用量、吸附体系pH值、吸附时间等对吸附效率的影响.结果表明,活性白土与壳聚糖的适宜配比为10∶1;复合物用量为6.000 g,吸附时间为45 min,pH为7时为Pb2+的适宜吸附条件,吸附率为90.21％;复合物用量为10.000g,吸附时间为45 min,pH为9时为Cu2+的最适吸附条件,吸附率为80.12％;复合物用量为8.000 g,吸附时间为60 min,pH为8时为Zn2+的适宜吸附条件,吸附率为70.31％.%This topic uses the activated clay and chitosan as raw materials,through the surfactant hexadecyl trimethyl ammonium bromide of activated clay chemical modification,the modified activated clay and chitosan are composited and prepared the target product-activated clayitosan complexes.The composites are characterized by infrared spectroscopy (IR),thermogravimetric (TG),X-ray diffraction (XRD) and transmission electron microscopy (TEM).The structure,thermal stability and morphology of the composites are investigated.Lamellar spacing of cetyl trimethyl ammonium bromide (CTAB) modified activated clay is 1.831 nm which increases to 2.299 nm.We research the effect of a single factor variable activity of clay and chitosan suitable ratio,adsorbent dosage,adsorption pH value,and adsorption time on the adsorption efficiency.The results show that the proper ratio of activated clay and chitosan is 10∶ 1,the complex dosage is 600 g,the adsorption time is 45 minutes,the suitable adsorption conditions for Pb2+ of the pH value is 7,and the adsorption rate is 90.21％.Besides,the dosage of composite is 10.000 g,the adsorption time is 45 minutes,the optimum adsorption conditions for Cu2+ of the pH value is 9,and the adsorption rate is 80.12％.Finally,the dosage of composite is 800 g,the adsorption time is 60 minutes,the suitable adsorption conditions for Zn2+ of pH value is 8,and the adsorption rate is 70.31％.