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With the rapid economic development and the continuous improvement of the national standard of living, interior decoration has become a fashion. However, it is a comfortable family life at the same time, is facing an increasingly prominent indoor air pollution problems. Currently, formaldehyde has become one of the indoor air pollution is the most common and most serious pollutants. Formaldehyde have a major impact on human health, eye, respiratory tract, skin have a strong stimulating effect, can lead to tears, nausea, vomiting, chest tightness, weakness and other symptoms, long-term exposure to low doses of formaldehyde can cause chronic respiratory disease, memory loss, chromosome abnormalities, immune dysfunction and so on. The World Health Organization (WHO) and the U.S. Environmental Protection Agency (U.S. EPA) classified formaldehyde as potentially dangerous carcinogens and environmental pollutants. The formaldehyde pollution problem has aroused widespread concern in society. Decoration used in water-based paint is one of the important sources of indoor formaldehyde pollution, and thus research Determination of formaldehyde in the paint method to reduce indoor pollution. Has been used in many ways - Determination of formaldehyde detection method in use today, but due to the complexity of the paint sample matrix diversity, the impact of interference components, the presence of sample pre-treatment time-consuming, complicated operation, poor selectivity, sensitivity , therefore, there is an urgent need to establish a simple, rapid, accurate water-based paint formaldehyde analysis method. 2,4 - dinitrophenylhydrazine derivatization and HPLC detection technology used in the determination of free formaldehyde content in the water-based paint. The main contents are as follows: (1) the detection of free formaldehyde in the aqueous coating sample pretreatment method. The selection and optimization of formaldehyde derivatization conditions. The sample was diluted with water, methanol and 2,4 - dinitrophenylhydrazine solution in acidic conditions derivative 60 ° C constant temperature water bath for 30 min, until the extraction of the organic solvent, directly detected by HPLC after centrifugation. (2) the establishment of free formaldehyde in water-based paint HPLC analysis. Detection wavelength, mobile phase chromatographic conditions were optimized, and ultimately determine the chromatographic conditions are as follows: C18 column, diode array detector, the detection wavelength was 354 nm, column temperature 30 ° C, flow rate of 1 mL / min, the injection volume was 20 ul of acetonitrile / water as the mobile phase, the retention time of the qualitative, quantitative standard curve. The results show that the method a good linear relationship in the range of 0.1 to 5.0 mg / L, the correlation coefficient R2 of 0.9997, and the detection limit of 0.99 mg / kg. Select water-based paint samples were 0.4 mg / L, 2 mg / L concentration added recovery experiments, recoveries ranged from 84.2% to 92.5% and the relative standard deviation lt; 5%. (3) high-performance liquid chromatographic analysis of formaldehyde in the establishment of water-based paint Uncertainty Evaluation, analysis of the sources of uncertainty in the measurement process, and each component was evaluated. The results show that the high performance liquid chromatographic method for the determination of formaldehyde content in water-based paint, the source of uncertainty is the standard curve fitting uncertainty introduced, reproducible determination of the uncertainty of the. (4) Comparison of high performance liquid chromatography, acetylacetone spectrophotometry two analysis methods conducted in-depth discussion on the results of the different types of water-based paint samples for determination of formaldehyde, and caused by the difference in outcome between.
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