在101.3 k Pa下,用改进的Othmer釜测定了乙酸乙酯-乙腈-1-辛基-3-甲基咪唑六氟磷酸盐([OMIM]PF_6)三组分物系的等压汽液相平衡数据,并应用NRTL模型对汽液相平衡的数据进行了关联。实验结果表明,[OMIM]PF_6对乙酸乙酯有明显的盐析效应;...在101.3 k Pa下,用改进的Othmer釜测定了乙酸乙酯-乙腈-1-辛基-3-甲基咪唑六氟磷酸盐([OMIM]PF_6)三组分物系的等压汽液相平衡数据,并应用NRTL模型对汽液相平衡的数据进行了关联。实验结果表明,[OMIM]PF_6对乙酸乙酯有明显的盐析效应;离子液体的加入使乙酸乙酯-乙腈二组分物系的汽液平衡曲线发生偏离,离子液体加入量越大,偏离程度越大;乙酸乙酯-乙腈-[OMIM]PF_6三组分物系乙酸乙酯的汽相摩尔分数的实验值与计算值的绝对平均偏差为0.004,温度平均偏差为0.4 K。展开更多
Using the ionic liquid（IL）1-octyl-3-methylimidazolium hexafluorophosphate as the extractant and methanol as the dispersion solvent,a dispersive liquid–liquid microextraction method was developed to extract silver n...Using the ionic liquid（IL）1-octyl-3-methylimidazolium hexafluorophosphate as the extractant and methanol as the dispersion solvent,a dispersive liquid–liquid microextraction method was developed to extract silver nanoparticles（AgN Ps）from environmental water samples.Parameters that influenced the extraction efficiency such as IL concentration,pH and extraction time were optimized.Under the optimized conditions,the highest extraction efficiency for AgN Ps was above 90% with an enrichment factor of 〉90.The extracted AgN Ps in the IL phase were identified by transmission electron microscopy and ultraviolet–visible spectroscopy,and quantified by inductively coupled plasma mass spectrometry after microwave digestion,with a detection limit of 0.01 μg/L.The spiked recovery of AgN Ps was 84.4% with a relative standard deviation（RSD）of 3.8%（n = 6）at a spiked level of 5 μg/L,and 89.7% with a RSD of 2.2%（n = 6）at a spiked level of 300 μg/L,respectively.Commonly existed environmental ions had a very limited influence on the extraction efficiency.The developed method was successfully applied to the analysis of Ag NPs in river water,lake water,and the influent and effluent of a wastewater treatment plant,with recoveries in the range of 71.0%–90.9% at spiking levels of 0.11–4.7 μg/L.展开更多
文摘在101.3 k Pa下,用改进的Othmer釜测定了乙酸乙酯-乙腈-1-辛基-3-甲基咪唑六氟磷酸盐([OMIM]PF_6)三组分物系的等压汽液相平衡数据,并应用NRTL模型对汽液相平衡的数据进行了关联。实验结果表明,[OMIM]PF_6对乙酸乙酯有明显的盐析效应;离子液体的加入使乙酸乙酯-乙腈二组分物系的汽液平衡曲线发生偏离,离子液体加入量越大,偏离程度越大;乙酸乙酯-乙腈-[OMIM]PF_6三组分物系乙酸乙酯的汽相摩尔分数的实验值与计算值的绝对平均偏差为0.004,温度平均偏差为0.4 K。
基金supported by the National Natural Science Foundation of China(No.21207124)Research Project of Beijing Municipal Education Commission(No.KM201110005009)the Special Fund for Quality Inspection Administration Public Welfare Scientific Research Funding(No.2012104001)
文摘Using the ionic liquid（IL）1-octyl-3-methylimidazolium hexafluorophosphate as the extractant and methanol as the dispersion solvent,a dispersive liquid–liquid microextraction method was developed to extract silver nanoparticles（AgN Ps）from environmental water samples.Parameters that influenced the extraction efficiency such as IL concentration,pH and extraction time were optimized.Under the optimized conditions,the highest extraction efficiency for AgN Ps was above 90% with an enrichment factor of 〉90.The extracted AgN Ps in the IL phase were identified by transmission electron microscopy and ultraviolet–visible spectroscopy,and quantified by inductively coupled plasma mass spectrometry after microwave digestion,with a detection limit of 0.01 μg/L.The spiked recovery of AgN Ps was 84.4% with a relative standard deviation（RSD）of 3.8%（n = 6）at a spiked level of 5 μg/L,and 89.7% with a RSD of 2.2%（n = 6）at a spiked level of 300 μg/L,respectively.Commonly existed environmental ions had a very limited influence on the extraction efficiency.The developed method was successfully applied to the analysis of Ag NPs in river water,lake water,and the influent and effluent of a wastewater treatment plant,with recoveries in the range of 71.0%–90.9% at spiking levels of 0.11–4.7 μg/L.
