Research On Methods For The Determination Of Mercury Species In Water And Sediment By High Performance Liquid Chromatography Combined With Atomic Fluorescence Spectrometry

With the development of society, all areas of life such as cosmetic products, industrial "three wastes" and even the people’s living garbage contain mercury which have caused significant pollution to the earth we depend on. Because of its special physical and chemical properties and toxicity, mercury has become a pollutant of global concern. Understanding the transformation of mercury speciation and accurate detection of mercury and its speciation in the environment is essential. Many methods for the detection of mercury and its speciations in environmental samples have been reports both in China and abroad, such as chromatography, atomic absorption spectrometry, gas chromatography, atomic fluorescence spectrometry and so on. These methods are mainly for extraction and detection of a particular form of mercury in environmental samples and cannot describe the mercury pollution in the environment scientific and reasonable.Innovation of this paper is that:we use two efficient modifier modified C18column to enrich mercury in water samples, and choose a kind of extract can be fully extracted mercury species in sediment samples. Methods for inorganic mercury, methylmercury and ethylmercury three mercury species determination in environmental water samples and sediment samples based on high performance liquid chromatography (HPLC) combined with hydride generation-atomic fluorescence spectrometry (HG-AFS) are proposed. The main work and conclusions are as follows:1. In this thesis, the determination of total mercury based on hydride generation atomic fluorescence spectrometry:negative high-pressure for PMT is280V, mercury lamp current is29mA, carrier gas flow rate is300mL/min, shielding gas flow rate of800mL min and atomization height is8mm.2. A method based on high performance liquid chromatography combined with hydride generation atomic fluorescence spectrometry for the determination of mercury and its compounds is proposed, and the conditions are optimized. Finalized detection conditions: mobile phase is5%acetonitrile+0.462%ammonium acetate+0.12%L-cysteine, a carrier for the5%HCl solution, and the reducing agent is0.5%(m/v) KOH+2%(m/v) KBH4, the oxidizing agent is0.5%(m/v) of KOH+1%(m/v) of K2S2O8, the UV lamp on, negative high-pressure for PMT is280V, mercury lamp current is30mA, carrier gas flow rate of300mL/min.3. The functionalized SPE cartridges combined with HPLC-UV-AFS process is an effeetive method for the determination of mercury species in environmental water samples. In the present study, a solid-phase extraction process can be easily accomplished by DDTC or2-mercaptoethanol modified C18column. Ultimately determine C18cartridges modified by5mL2-mercaptoethanol eluted with2mL mobile phase containing10%acetonitrile,5mL DDTC modified C18column eluted with5mL mobile phase containing10%acetonitrile.4. Based on the existing experiment, a extraction and detection method of mercury species in sediment is established. Select10%HCl+1%thiourea+0.15%KCl as the extract.