Preconcentration Of Benzo[a] Pyrene In Water Samples By Synchronous Fluorometry Spectrometry After Cloud-point Extraction

With the rapid economic development, the environment situation is deteriorating day by day. Water pollution, which is a very serious threat to people's health and social stability, is important somthing we should be concerned about. Because of water scarcity, water supply shortages may get worse if water pollution doesn't be controled. How to detect and control water pollutants is a powerful environmental determinant of assurance of water safety. Organic pollutants are chiefly characterized by lots of toxicities and varieties, widespread, low concentration and complexity. So organic pollutants, especialy persistent organic pollutants (POPs) represented by polycyclic aromatic hydrocarbons (PAHs), should be paid more and more attention. Benzo[a]pyrene (Bap) is a typical and important because of its sever carcinogenic and most widely spread. The separation of PAHs is essential for water quality. The traditional separation methods showed a lot of disadvantages, such as wasting too much organic solvent and time. It is significant to develop a sample and rapid preconcentration method with a high efficiency and sensitivity. The cloud point extraction (CPE) is a new separation method, offering many advantages including low cost, high efficiency. Owing to the advantages mentioned above, CPE has been used widely in environmental samples, biological moleculars.Many test methods, such as gas chromatography (GC) and high performance liquid chromatography (HPLC), can be applyed to detect PAHs. HPLC and GC have showed their performances on separation and testing, but they cost too much, and also waste too much on preconcentration. Compared with HPLC and GC, the synchronous fluorescence spectrometry has its advantangs, such as high selectivity, simplified spectum and so on.The efficiency of CPE is influenced by the surfactant concentration, the equilibration time, pH and so on. The thesis showed the study in the cloud point and phase separation of Triton X-114 and Tergitol 15-S-7, and its recovery to benzo[a]pyrene, in term of benzo[a]pyrene preconcentration which features high efficiency and simple.It showed that the cloud point is irrelative about the surfactant concentration with its above 2%. When the surfactant concentration is less than 1%, the cloud point is elevating instantly with the decreasing of the surfactant concentration. The cloud point showed obvious changes when the addition agents existed. The cloud point is positive correlation with the concengtration of HCl, but negative correlation with the concentration of NaCl. The surfactant concentration effected hardly on the cloud point when the addition agents existed.It needs a lot of time on the equilibration with static. The additions can make the equilibration time contraction, but it also cost many hours for equilibration. Centrifugation is an efficiency method for phase separation.The efficiency is influenced by the surfactant concentration and innial concentration of benzo[a]pyrene. With the surfactant concentration increasing, the efficiency showed elevating and then decreased. It is negative correlation with innial benzo[a]pyrene concentration.The spiked recoveries of water samples were from 95.8% to 102% for triton X-114, and 96.5% to 101.1% for tergitol 15-S-7. The good linearity was in range 0-0.11 mg/L; detection limits 0.03μg/L; RSD of standard solution 3.42%...