碳氮分析仪测定造纸法再造烟叶中的碳酸钙含量

建立了碳氮分析仪法测定造纸法再造烟叶中碳酸钙含量的方法。通过热催化高温氧化反应对样品进行消解,检测经高温分解产生的CO_2气体,分别用不同的前处理方法,测定样品中的总碳和有机碳,用差量法计算出无机碳后,依据碳和碳酸钙分子量的换算,计算得出样品中碳酸钙的含量。结果显示:①待测液线性响应对应的最高碳含量为36mg;②样品本底碳量为14.5mg时,当加标碳量分别为2.5、5.0、7.0mg时平行检测3次的变异系数分别为7.60%、6.25%、3.77%;③方法的回收率范围为85.96%～111.16%;④方法的检出限和定量限分别为0.013mg和0.04mg。方法适合于测定造纸法再造烟叶中碳酸钙的含量。

Determination of Calcium Carbonate in paper-Process Reconstituted Tobacco by Carbon and Nitrogen Analyzer

A carbon and nitrogen analyzer method was established to determine the content of calcium carbonate in pape-process reconstituted tobacco leaves. The sample is subjected to digestion by thermal catalytic high-temperature oxidation reaction, and the CO_2 gas generated by pyrolysis is detected.The total carbon and organic carbon in the sample are determined by different pretreatment methods, and the inorganic carbon is calculated by the total carbon minus organic carbon. Then the content of calcium carbonate in the sample was calculated by conversion to the molecular weight of calcium carbonate. The results showed that: 1. the highest carbon content corresponding to the linear response of the liquid to be tested was 36 mg; 2. when the background carbon content of the sample was 14.5 mg, and the spiked carbon amounts were 2.5, 5.0, and 7.0 mg, the coefficient of variation of the 3. parallel detections were7.60%, 6.25%, and 3.77% respectively. 3. The recovery range of the method was 85.96～111.16%; 4. the detection limits and quantitation limits of the four methods were 0.013 mg and 0.04 mg, respectively. In conclusion, the method is suitable for determining the content of calcium carbonate in paper-process reconstituted tobacco leaves.