【摘要】 三氟乙酸是HFC-134a等氯氟烃替代品的降解产物,对植物和土壤微生物群落的生长有一定抑制作用。笔者建立了测定TFA质量浓度的实验方法:将样品中的三氟乙酸与硫酸二甲酯在浓硫酸介质中衍生为三氟乙酸甲酯(MTFA),利用MTFA的易挥发性,以顶空进样和气相色谱-质谱联用的方法检测样品中MTFA的质量浓度,进而得到环境水样中TFA的质量浓度。并应用该方法测定了北京部分地表水体中三氟乙酸的质量浓度。测定结果:北京青年湖水样和北海水样中的ρ(三氟乙酸)分别为78和93ng L,而北京大学自来水水样中ρ(三氟乙酸)低于方法检测限10ng L。更多还原

【Abstract】 Trifluoroacetic acid(TFA) is degradation product of some CFCs alternatives,such as HFC-134a,which has some inhibitory effects on plants and soil microbial communities.In concentrated sulfuric acid TFA may change into MTFA with dimethyl sulfate(DMS),so it is possible to obtain the mass concentration of TFA in water samples by determining the mass concentration of MTFA with headspace sampling and GC-MS,using the volatility of MTFA.The method to determine the mass concentration of TFA is built by the authors,and is used to determine TFA in some surface water samples of Beijing.Among these samples,TFA in Qingnianhu Lake and Beihai Lake is 78 and 93 ng/L respectively,while that in tap water of Peking University is under the detection limit,10 ng/L.更多还原