Gas Chromatography trimethyl tin chloride Method
|Course||Of Food Science|
|Keywords||Trimethyl tin chloride Organotin GC Detect|
Plastic and human lives, PVC plastic production in the world's second, widely used in water supply pipes and food and drug packaging. PVC processing, must be added to a large number of plasticizers, stabilizers other supporting materials. Organotin its good performance become essential in PVC processing heat stabilizers, and organotin methyl tin stabilizing effect of the best kind. Trimethyl tin chloride (TMT) is a major by-product methyl tin, is a highly toxic compound that has a good fat-soluble and water-soluble. China has witnessed a number of TMT poisoning death 10 people. Use of high levels of TMT stabilizers and scrap plastic as raw material is caused by the direct cause of poisoning. The country has not addressed the limited trimethyl tin chloride standards and testing methods, so to establish a convenient, fast, broad-spectrum detection method is very necessary. The main contents of this paper: first established liquid-liquid extraction - gas chromatography PVC packaging materials TMT method, GC-ECD has spread wide range of features, the establishment of the Act for the establishment of national standards for data provide some support, and the method can be used for TMT fieldworkers pollution monitoring and investigation. Randomly selected from commercially available for different uses 20 kinds of PVC products, including pipes, films, bags, cups, sheets and bottle washer, the use of liquid-liquid extraction - gas chromatography for its detection, and the results were statistically analyzed. Through experimental study obtained the following results: 1. Detection of sample preparation: The sample after immersion, using ethyl acetate as the extraction liquid extract three methyl chloride, and nitrogen blowing concentrated to 1mL, injection lμL, GC-ECD analysis. If the sock liquid is water or 4% of acetic acid, saturated sodium chloride must be added, and then adjust the PH value to 6.6-7.6, and then extracted. Optimal chromatographic conditions: column was DB-17 capillary column (0.25μm × 0.25mm × 30m) Inlet temperature: 200 ℃, column flow rate: 1.0 mL / min; column temperature: 60 ℃ maintained 7min, to 25 ℃ / min to 200 ℃, keeping 2min; detector temperature: 260 ℃, makeup flow: 40 mL / min; splitless 1μL, split ratio of 5:1, the total analysis time 14.6 min. (2) using this method for more than 20 kinds of samples conducted a sample survey, using ethyl acetate as soaking, tested 12 samples, positive samples two parts, the detection rate of 16.7%, and its content is 0.40mg/kg, 20.32 mg / kg; with 4% acetic acid for soaking, 10 samples tested positive sample 1, the detection rate of 10%, the content 1.2μg / L; with water as a soaking, 10 samples tested were not detected positive. Using the GC / MS method for detection of data were compared, the results show true and reliable test results. 3 The law is simple, easy to spread the advantages, but for some samples has not yet reached the sensitivity testing requirements, the interference of the sample matrix on the determination of further research is needed.