摘要:
以罗耳阿太菌多糖(Athelia rolfsii polysaccharide,AEPS)为生物吸附剂,探究其对水中铜(Cu2+)和镉(Cd2+)重金属离子的吸附。在单因素实验的基础上,采用正交试验优化AEPS吸附Cu2+和Cd2+效果,通过扫描电子显微镜(SEM)、X射线能谱仪(EDS)和傅里叶红外光谱仪(FTIR)对AEPS吸附重金属离子前后的表面形貌进行表征和分析,初步揭示了AEPS吸附Cu2+和Cd2+机理。结果表明,Cu2+吸附效果最优条件为:pH4.5,AEPS浓度1.5 g/L,吸附温度40 ℃,吸附时间45 min时,Cu2+吸附率为88.27%;Cd2+吸附效果最优条件为:pH6.5,多糖浓度1.5 g/L,吸附温度45 ℃,吸附时间60 min时,Cd2+吸附率为77.81%。SEM、EDS和FTIR结果表明,AEPS中的O-H、C-H、C-O和CCO官能团参与吸附反应,吸附Cu2+和Cd2+的AEPS的表面结构也发生明显变化,试验结果表明AEPS对Cu2+和Cd2+有良好的吸附作用。
Abstract:
To explore the adsorption on copper and cadmium heavy metal ions in water by using Athelia rolfsii polysaccharide as a biosorbent. On the basis of single factor experiments,the orthogonal experiment was used to optimize the adsorption effect of Cu2+ and Cd2+ by AEPS. The surface topography of polysaccharides before and after adsorption of heavy metal ions were characterized and analyzed by scanning electron microscope(SEM),X-ray energy dispersive spectrometer(EDS)and Fourier transform infrared spectroscopy(FTIR),and the adsorption mechanism of AEPS on Cu2+ and Cd2+ were initially revealed. The results of the optimal conditions for Cu2+ adsorption were pH4.5,AEPS concentration 1.5 g/L,adsorption temperature 40 ℃,and adsorption time 45 min,the Cu2+ adsorption rate was 88.27%. The optimal conditions for Cd2+ adsorption were pH6.5,polysaccharide concentration 1.5 g/L,adsorption temperature 45 ℃,and adsorption time 60 min,the Cd2+ adsorption rate was 77.81%. The results of SEM,EDS and FTIR indicated that the O-H,C-H,C-O and CCO functional groups in AEPS were involved in the adsorption reaction,and the surface structure of AEPS adsorbing Cu2+ and Cd2+ also changed significantly. The results showed that AEPS had a good adsorption effect on Cu2+ and Cd2+.