Studies On The Measurement And Identification Method Of Petroleum Pollutants Based On Three-dimensional Fluorescence Spectroscopy

Petroleum as an important energy and chemical raw materials bring benefit to humanbeing and create tremendous economic value for society, but also does harm to theecological environment. Marine oil spill accidents take place frequently, petroleumsubstances make water polluted seriously, and human health has been threatenedultimately. Identification and measurement of petroleum pollutants have became animportant tool in identifying pollution sources, controlling pollution and protecting theenvironment.Fluorescence Spectroscopy technology is an important means of detecting petroleumpollutants with the advantages of high sensitivity, good selectivity, analysis rapidly, smallweathering effects. Thesis focuses on limited identification capacity of fluorescencespectroscopy and serious spectral overlap problem of multi-component petroleumsubstances mixed system. Three-dimensional fluorescence spectroscopy combined withthe second-order calibration methods in chemometrics is applied to identify and analyzecomplex systems of petroleum substances effectively.Making good full use of the fluorescence spectrum information, chemicalcomposition and fluorescence characteristics of petroleum pollutant are researched, andthe feasibility of using fluorescence spectroscopy to identify and measure the variety ofpetroleum pollutants such as crude oil or petroleum products is determined. Structuralprinciple, performance, various parameter settings and scattering affects to measurementof the measuring instrument are researched. Correction methods from apparent spectrumto the true spectrum to eliminate various factors making the spectral distortion arediscussed in detail and three-dimensional fluorescence spectra of samples are obtained.The varying on the fluorescence spectra of petroleum products with concentration isresearched, and the problem on poor solubility, stability of oils in water is solved. Throughmeasuring fluorescence spectra of the same kinds of petroleum products in differentsolvents and different petroleum products in the same solvent, the differences betweenfluorescence spectra are discussed. The fluorescence spectra of various different concentrations petroleum products in ethanol diluted solution are measured, and spectralcharacteristics and differences on the composition of the chemical nature from each of thepetroleum diluted solution are verified. The concentration-dependent wavelength shifts inthree-dimensional fluorescence of petroleum samples and red-shift cascade areinvestigated. Linear relationship between concentration and fluorescent intensity ofpetroleum solution are ensured. The measurement principle and method of each petroleumproducts in surfactant micelle solution as an ordered medium are researched and thefluorescence spectra of them are measured. The feasibility and accuracy of quantitativeanalysis using it to enhance the fluorescent intensity are verified.Second-order calibration methods in chemometrics are used to analyze fluorescencespectra of mixed petroleum substances and solve identification and quantification problemof complex multi-component mixed petroleum pollutants. By mixing two or three type ofpetroleum products of different concentrations as calibration sample set and predictionsample set, the three-dimensional fluorescence spectra of samples in calibration set andprediction set are measured. Combining core consistency diagnosis and explained varianceof each factor to ensure optimal number of factor, PARAFAC model is built to analyze thethree-dimensional data and fluorescence loading spectra is obtained correctly.Fluorescence spectra of mixed samples added interference components in are measured,and the second-order advantage of second-order calibration methods is verified byPARAFAC and SWATLD algorithm.