State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China.
J Chromatogr A. 2014 May 23;1343:42-6. doi: 10.1016/j.chroma.2014.03.066. Epub 2014 Apr 3.
This paper reports on the development of a new headspace analytical technique that is based on water removal by hydrate formation (WRHF). By adding anhydrous salt, the liquid water in an aqueous sample will be removed leaving behind volatile analytes that are fully vaporized at temperatures well below their boiling points. With WRHF, the amount of sample in the headspace can be significantly increased, thereby dramatically improving the detection sensitivity. The technique reduces the risk of possible column damage in gas chromatography (GC) systems. The technique was applied to the determination of phenol at different stages of a coking wastewater treatment plant. The results showed that up to mL-levels of sample solution can be used in WRHF HS-GC analysis when 5g of CaCl2 were used as the anhydrous salt. The detection sensitivity for phenol content was 500 times greater than that in earlier HS-GC work that did not incorporate hydrate formation. The proposed WRHF headspace analysis technique is simple and practical, making it a useful tool for quantifying low concentrations of volatile analytes in aqueous samples.
本文报道了一种新的顶空分析技术的发展，该技术基于水合物形成（WRHF）去除水。通过添加无水盐，水样中的液态水将被去除，留下挥发性分析物，这些分析物在远低于沸点的温度下完全蒸发。通过 WRHF，可以显著增加顶空样品的数量，从而大大提高检测灵敏度。该技术降低了气相色谱（GC）系统中可能出现的柱损坏风险。该技术应用于焦化废水处理厂不同阶段的苯酚测定。结果表明，当使用 5g 氯化钙作为无水盐时，WRHF HS-GC 分析中可以使用高达 mL 级别的样品溶液。与早期未采用水合物形成的 HS-GC 工作相比，苯酚含量的检测灵敏度提高了 500 倍。所提出的 WRHF 顶空分析技术简单实用，是定量分析水样中低浓度挥发性分析物的有用工具。
