电阻炉燃烧-红外吸收法测定多钒酸铵中硫

应用电阻炉加热的红外碳硫仪，测定了富含结晶水的多钒酸铵中硫。利用样品分解残留物（V2O5）的助熔作用，直接测定样品中硫，结果发现，称样量为200 mg，燃烧温度为1 370 ℃时，多钒酸铵分解产生的大量H2O和NH3未对硫的测定产生影响。研究表明，采用在V2O5中加入系列硫标准溶液建立校准曲线，结果可靠。用本方法测定了硫质量分数在0.08%～0.40%的样品，测定结果与硫酸钡重量法结果相吻合，相对标准偏差为0.50%～1.4%（n=8）。

Determination of sulfur in ammonium polyvanadate by resistance furnace combustion-infrared absorption method

The content of sulfur in ammonium polyvanadate rich in crystal water was determined by infrared carbon-sulfur analyzer with resistance furnace heating. Through the fluxing action of residue (V2O5) by sample decomposition, the content of sulfur in sample was directly determined. The results showed that a mass of H2O and NH3 generated due to the decomposition of ammonium polyvanadate had no influence on the determination of sulfur with sampling weight of 200 mg and combustion temperature of 1 370 ℃. It indicated that the calibration curve created by adding sulfur standard solution series into V2O5 was reliable. The proposed method has been applied to the determination of samples containing 0.08%-0.40% (mass fraction) of sulfur. The results were consistent with those obtained by barium sulfate gravimetric method with relative standard deviations (RSD, n=8) of 0.50%-1.4%.