海水和大气中挥发性硫化物分析方法的研究

建立了大气和海水中挥发性硫化物的气相色谱分析方法,确定了最佳实验条件.为了适应不同的基质和保存方式,大气和海水样品采用了不同的分析方法.测定大气样品时,采用大气采样罐及三级冷阱预浓缩气相色谱-质谱联用技术,而海水样品采用吹扫捕集-气相色谱测定.本方法测定大气挥发性硫化物的线性范围较好,精密度为7.7%~15.1%,检出限为0.23~4.7 ng;海水中挥发性硫化物的精密度为3.5%~5.3%,检出限为2.5~3.5 ng.将本方法用于青岛近海海水和大气中硫化物的测定,测得海水中羰基硫、二甲基硫和二硫化碳的平均浓度分别为(268±58)pmol/L、(1264±0.2)pmol/L、(19±2)pmol/L,大气中的平均浓度为543±39、39±9和56±20(×10-12,V/V).本方法可准确测定海洋环境中的挥发性硫化物.

Determination of Volatile Sulfur Compounds in Seawater and Atmosphere

Volatile sulfur compounds ( VSCs) in the marine environment has significant implications for global climate change. In the present study, a gas chromatographic analytical method was set up to determine the concentrations of VSCs in seawater and atmosphere, and the optimized experimental conditions were established. For the analysis of VSCs in atmosphere, multistage traps and gas chromatography-mass spectrometry ( GC-MS ) were used, with the precisions of 7. 7% -15. 1% and the detection limits of 0. 23-4. 7 ng. Moreover, for the analyses of VSCs in seawater, pre-concentration and gas chromatography coupled with flame photometric detector ( GC-FPD) were utilized, with the precisions of 3. 5%-5. 3% and the detection limits of 2. 5-3. 5 ng. This method was applied to analyze the VSCs in Qingdao coastal seawater and atmosphere, and the average concentrations of carbonyl sulfide, dimethyl sulfide and carbon disulfide in the seawater were (268 ± 58 ) , ( 1264 ± 278 ) , ( 19 ± 2 ) pmol/L, and ( 543 ± 39 ) , ( 29 ± 9 ) , ( 56 ± 20 ) ( ×10-12 , V/V) in the atmosphere, respectively.