液体闪烁计数法鉴别生物质基泡沫材料

Identification of the Bio-based and Petroleum Based Foam

基于美国材料实验协会ASTM D6866标准,利用超低本底液体闪烁技术,测定不同原料来源的泡沫材料中放射性碳同位素^(14)C含量,转化为生物基含量,从而用于鉴别生物基泡沫材料。实验中,分别利用元素分析和热重分析确定样品用量及其氧化燃烧温度,样品燃烧后产生的二氧化碳经过一系列化学反应合成为液体苯,通过测定合成苯中的放射性碳同位素^(14)C含量来区别鉴定生物质基泡沫材料和石油基泡沫材料,同时测定本底物质煤炭和标准物质糖碳中的^(14)C含量。结果表明:采用该方法测定的糖碳标准物质的^(14)C放射性活度值与标准值一致,由生物质基泡沫材料的^(14)C放射性活度值测定结果计算得到的生物基含量结果与美国Beta实验室采用加速器质谱(AMS)方法测试的结果一致。4种泡沫样品的生物基含量分别为18.77%、23.51%、5.39%和11.13%,全部为生物质基泡沫材料。说明利用该方法能够鉴别生物质基泡沫材料与石油基泡沫材料。

The14C content in the bio-based foam was determined by liquid scintillation based on ASTM D6866 method.Identification of the bio-based and petroleum based foam was based on the different biobased content. In this experiment,the sample quality is determined by the elemental analysis. The temperature of the ignition experiment is dependent on TG. After combustion,the sample was converted to carbon dioxide. Through a series of chemical reactions,it was synthesised to be liquid benzene. Through the determination of radioactive carbon isotope,content of14 C in benzene was used to identify biomass based foams and petroleum based foam. The background coal and standard substance sugar carbon were detected simultaneously. The results showed that the14 C radioactivity values of sugar carbon were the standard value,and the results of biobased content result is in agreement with that of the American Beta laboratory by using accelerator mass spectrometry（ AMS） method. The bio-based content of four kinds of foam samples are 18. 77%,23. 51%,5. 39% and 11. 13%,respectively. They all are bio-based foam. It indicates that the bio-based foam and the petroleum based foam can be identified by this method.