利用微生物催化丙烯腈生产丙烯酰胺在工业上已经得到了广泛的应用。生产中反应液同时含有底物丙烯腈、产物丙烯酰胺以及副产物丙烯酸。为了控制产品质量,需快速定量检测反应液中各组分。采用毛细管柱PEG-20M(30m×0.25mm i.d.,2μm),以20g/L的乙酰胺作为内标物对反应液进行气相色谱分析,优化分析条件为:进样口为SPL,温度260℃;FID检测器,温度260℃;柱温190℃;载气为氮气,流速25cm/min;分流进样,进样量0.4μL,分流比为50:1。在4min内,3个组分得到完全分离,该方法具有良好的重现性和线性关系,回收率分别为98.5%、102.1%、105.0%,相对标准偏差分别为9.1%、5.3%、1.7%。该方法分析速度快,适合实验室与工厂生产中大量快速定量检测样品。
Products of acrylamide from acrylonitrile with microbial enzymes as the biocatalyst has recently become pepular in industry. During the biotransformation process, substrate acrylonitrile, product acrylamide and by-product acrylic acid will be simultaneously present in the reaction solution. In this study, a capillary column PEG - 20M (30 m × 0.25 mm i.d., 2 μm) was selected to quantitatively measure the concentrations of acrylonitrile, acrylic acid and acrylamide, with acetamide as the inner standard. The optimal temperatures of the SPL sample receiver, the FID detector and the column were determined to be 260, 260 and 190 ℃, respectively, with nitrogen as the carrier at the speed of 25 cm/min. The injection volume of the sample was set at 0.4 μL with the shunting ratio of 50: 1. Final restilts showed that the three targets can be completely separated within 4 min, with high reproducibility and linearity. The reovefies of acrylonitrile, acrylic acid and acrylamide reached as high as 98.5%, 102.1% and 105.0%, with the relative standard deviation of 9.1%, 5.3 % and 1.7 %, respectively. These results show this method is simple,accurate and has a very promising prospect in the highhroughput quantitative analyses of acrylonitrile, acrylamide and acrylic acid in both lab and industry.