Study Compositions Of Gasoline And Polytetrahydrofuran By Near Infrared Spectroscopy

Near Infrared (NIR) Spectroscopy method is one of the most promising technologies with high-speed development in analytical technology and has been widely used in the field of analysis on fuels property and various chemical processing controls.The detailed research has been carried out on the chemical content of gasoline by NIR Spectroscopy technique. Various types of 96 gasoline samples that come from some domestic large refineries have been collected up to predict the chemical contents by NIR spectroscopy technique. Gas Chromatography (GC) as standard data for module establishment had determined the chemical contents including detailed hydrocarbon and PONA. After connected NIR spectrum with chemical content by means of Partial Least Square (PLS), nine calibration models were set up to test on the chemical content of gasoline, which is as below: paraffines, isoalkanes, cycloparaffin. saturated hydrocarbon, olefins, aromatics, benzene, toluene, xylene, (including paraxylene. metaxylene. orthoxylene and ethylbenzene). The results of calibration set sample cross validation and the test set sample validation proved that NIR method based on the fact was of good accuracy and the deviation between NIR and GC was less than 0.5%. the results of the paired t test also show that there is no obvious difference between NIR method and standard method. In conclusion, it is applicable to analyze the gasoline samples by the measures of NIR.Explored the feasibility of NIR analysis on water content, solid content and relative molecular mass in PTMEG mixed solution. The standard data for mathematical model establishment come from the figure such as water content by Microcoulomb equipment, solid content by loss of weight of Volatilization and PTMEG relative molecular mass by Gel Chromatography (GPC). Advised to indirectly determine the relative molecular mass of PTMEG via NIR technique, establishing the connection between relative content of PTMEG hydroxy group of mixed reagent system and relative molecular mass, which is definite physical meaning, good compatibility with NIR spectrum and satisfactory result. After pre-processed on NIR spectrum for PTMEG mixed solution by first derivative, the sensitivity and accuracy of the method had been relatively developed with good result. The test results by NIR and those by standard method had little differencewithin the scope of NIR module that relative deviation was less than 5%. The study proved that the presented method has a good repeatability and accuracy and can be applied to on-line detection in industrial process.The NIR method has characteristic of simple operation, quick analyzing, little consumption on organic reagent and good accuracy in testing on chemical content of gasoline and PTMEG mixed reagent. The method could be used in processing control and site quality control. Application of the on-line near-infrared (NIR) spectroscopy process analytical technique can reduce the cost on process control, largely improve the capacity of process control, analysis level, enhance the whole productivity and economic efficiency. The petrochemical corporation will be beneficial on the side of material balance and optimization, the purchasing and marketing of raw material and the production scheduling and logistics.