氟氯烃替代品降解产物三氟乙酸的环境影响研究

As CFCs causes depleting of the ozone layer, worldwide efforts have been made to reduce and phaseout the production and consumption of CFCs by "MONTREAL PROTOCOL FOR THE OZONE DEPLETING SUBSTANCES". Chinese government ratified the protocol, and obtained the progress on ODS phaseout action.As the adopting of alternatives of ODS, their end-product would been found in the atmosphere. One of the product from degradatuon of HCFC123，HCFC124 HFC-134a is trifluoroacetic acid (TFA) that be easily accumulated in waters and resulting adverse impact on environment.Reports concerning the studies of TFA and its impacts on environment are rare in overseas publications. So far, no study on the subject has been conducted in China. Consequently, it is critically important and extremely meaningful to understand the status of existence of TFA in the environment in China. This will create background reference for the effects of TFA in the environment prior to the extensive consumption of alternatives of ODS in China. Under support of NSFC, a set of analytical method was established for studying the effects of TFA on the invironment.The pre-treatment measures and derivatization method for collecting, preserving and concentrating environmental samples in different kind of environmental systems was established. The electrical capture detector-headspace auto sampler--GC system was selected with 0.0004ng limit of detection of the instrument and 3ng/ml limit of detection of the analytical method. The recovery level of 84-92% for standard samples and 75-93% for actual environmental samples was determined.The various environmental samples including rainfall, surface water, underground water from different provinces were analyzed by applying the TFA analytical methods.Nine rainfall through the period from 2000 to 2001 in Beijing were monitored and analyzed. The results indicate that the concentration s of TFA ranged from 25 to 220ng/L. For the snow samples collected from Beijing and Changchun, the concentration of TFA ranged from 98 to 169ng/L.The concentration of TFA found in water samples collected from different parts of several lakes in diffirent locations in Beijing and in different seasons ranged 23-138ng/L.Water samples were also collected and analyzed from major rivers and lakes around China, with congcentration of TFA 4-221ng/L..The results of the project are establishment of the analytical method for researching and monitoring TFA's impacts on the environment in China and The information concerning the concentrations of TFA in the environment of China was obtained, which settles the foundation for further studies on impacts of alternatives of CFCs in the future.

该项研究将启动我国氟里昂替代品的降解产物三氟乙酸的研究，建立我国的标准分析方法，全面分析我国现阶段大气、地表水、海洋中三氟乙酸的含量，提供有关三氟乙酸的背景资料，填补我国在该领域的研究空白。为氟里昂替代品对环境的潜在危害提供一定信息，在目前没有全面使用氟里昂替代品的情况下，适时测定湿地生态系统的三氟乙酸背景值。