针对水体中砷污染日益严重问题,选用五种不同的铁盐对活性炭进行改性,采用高温蒸发法制备复合材料(GAC-Fe);利用X射线衍射(XRD)和红外光谱(FTIR)对复合材料进行表征;研究了修饰物投加量、铁盐质量、反应液pH值和温度对砷吸附效果影响。结果表明,活性炭负载FeSO_4·7H_2O,投加5 mL H_2O_2制备的复合材料效果最佳;铁盐投加量越多,复合材料的铁含量和吸附容量均增加,但铁析出量也迅速增加;吸附砷在中性条件下效果较好;温度与吸附容量呈负相关,其最大吸附容量为2.551 mg/g;解析实验表明复合材料解吸率达80%,有利于吸附后砷的收集。
A simple and rapid technique based on liquid-liquid extraction coupled to gas chromatography-mass spectrometric detection(LLE-GC-MS) was developed for analysis of taste and odour compound β-ionone in water. Instrument parameters including programmed oven temperature, injection temperature and ion source temperature were evaluated and optimized. Effects of extraction time, ionic strength and p H on the detection efficiency were investigated and optimum conditions were 8 min of extraction time, without Na Cl addition at p H=9. Good linearity(R2=0.9997) was obtained when the linear range was 10-500 μg/L. The recoveries of β-ionone in ultrapure water and tap water samples were 88%-95% and 110%-114%, respectively. The relative standard deviations(RSD) were less than 10%. The method detection limit(MDL) and rejection quality level(RQL) were achieved at1.98 μg/L and 6.53 μg/L, respectively. LLE-GC-MS was demonstrated to be a rapid and convenient method for the determination ofβ-ionone in water samples.
