自动快速燃烧炉-离子色谱法测定煤炭中氯

IC Determination of Chlorine in Coal with Automatic Quick Furnace

采用自动快速燃烧炉-离子色谱法测定煤炭中氯的含量。优化的试验条件如下:(1)燃烧管进口温度为950℃,出口温度为1 050℃;(2)称样量为10 mg;(3)以4.5 mmol·L^(-1)碳酸钠-1.4mmol·L^(-1)碳酸氢钠混合液为吸收液。以阴离子色谱柱为分离柱,4.5 mmol·L^(-1)碳酸钠-1.4mmol·L^(-1)碳酸氢钠混合液为淋洗液,抑制型电导检测器测定。以PO_4^(3-)作为内标物,氯的线性范围为0.5~20μg·L^(-1),检出限(3S/N)为0.086mg·L^(-1)。方法应用于煤炭标准物质和实际样品的分析,测定值与认定值相符,测定值与国家标准方法的测定结果相符,测定值的相对标准偏差(n=6)为2.4%~7.5%。

IC was applied to the determination of chlorine in coal with automatic quick furnace.The optimized conditions found were as follows：（1） inlet temperature and outlet temperature of combustion tube were 950,1 050 ℃ respectively;（2） sample weight was 10 mg;（3） mixture of 4.5 mmol·L-1 Na2CO3 and 1.4 mmol·L-1 NaHCO3 solution was used as absorbent.Anion chromatographic column was used for chromatographic separation,mixture of 4.5 mmol·L-1 Na2CO3 and 1.4 mmol·L-1 NaHCO3 solution was used as eluant,and restraining conductance detector was used in determination.PO43-was used as internal standard.Linearity range of chlorine was in the range of 0.5-20μg·L-1,with detection limit（3S/N）of 0.086 mg·L-1.The proposed method was applied to the analysis of standard materials and actual samples of coal,giving results in consistency with the certified values and the values obtained by the GB method.RSD′s（n=6）found were in the range of 2.4%-7.5%.