Cappiello Achille, Famiglini Giorgio, Palma Pierangela, Pierini Elisabetta, Trufelli Helga, Maggi Chiara, Manfra Loredana, Mannozzi Michela
Istituto di Scienze Chimiche F. Bruner, Università di Urbino, Piazza Rinascimento 6, 61029 Urbino, Italy.
Chemosphere. 2007 Sep;69(4):554-60. doi: 10.1016/j.chemosphere.2007.03.026. Epub 2007 May 11.
Diethylene glycol (DEG) is extensively used on offshore gas platforms to prevent the hydrate formation during the gas-water separation process and to inhibit corrosion events. This chemical might enter in the marine environment via the produced formation water (PFW) discharge. In this study, a new approach was applied to the investigation of the DEG content in PFW discharges and seawater samples from four gas installation platforms in the Adriatic Sea (Italy). The method includes an off-line solid-phase extraction/pre-concentration technique, followed by a nanoscale flow injection/direct-electron ionization (EI) mass spectrometric analysis. Direct-EI is a novel and miniaturized interface for directly coupling a liquid chromatograph with an electron ionization mass spectrometer. The capability to acquire EI spectra, and to operate in selected ion monitoring mode during actual sample analyses, allowed a precise quantification of DEG with a method limit of detection of 31microg/l. In addition, a careful evaluation of the matrix effect showed that, as opposed to electrospray ionization, the response of the Direct-EI interface was not affected by sample interferences.
二甘醇（DEG）在海上天然气平台被广泛用于防止气水分离过程中形成水合物以及抑制腐蚀。这种化学物质可能会通过采出地层水（PFW）排放进入海洋环境。在本研究中，一种新方法被应用于调查亚得里亚海（意大利）四个天然气设施平台的PFW排放物和海水样品中的DEG含量。该方法包括离线固相萃取/预浓缩技术，随后进行纳米级流动注射/直接电子电离（EI）质谱分析。直接EI是一种用于直接将液相色谱仪与电子电离质谱仪联用的新型小型化接口。在实际样品分析过程中获取EI光谱以及在选择离子监测模式下运行的能力，使得能够以31微克/升的方法检测限对DEG进行精确量化。此外，对基质效应的仔细评估表明，与电喷雾电离不同，直接EI接口的响应不受样品干扰的影响。
