高频炉燃烧红外吸收法测定钛精矿中硫

Determination of sulfur in titanium concentrate by high frequency furnace combustion infrared absorption method

对于钛精矿中硫的测定,现有标准方法为燃烧-碘量法,该方法的分析流程较长,不适合大批量样品的分析;同时方法的测定范围有限,仅适合硫质量分数在0.025%~0.500%的样品。为适应现有钛精矿的生产和科研需要,实验建立了高频炉燃烧红外吸收法测定钛精矿中硫的分析方法。对样品量、燃烧用助熔剂种类及用量等测试条件进行了优选。确定的最佳分析条件为:称取0.40 g样品于坩埚中,加入0.5 g锡粒、0.3 g纯铁屑、1.3 g钨粒助熔剂进行测定。采用钛精矿标准样品分段绘制硫的校准曲线,硫质量分数的测定范围为0.0048%~2.76%;方法定量限为0.0006%,完全满足现有钛精矿的测定需求。对硫质量分数在0.0092%~1.51%的钛精矿样品进行了测定,测定值的相对标准偏差(n=8)为0.33%~1.8%。实验方法的测定结果与硫酸钡重量法吻合,对低硫样品的加标回收率为90%~105%。

The current standard method for the determination of sulfur in titanium concentrate is combustion-iodometry.But the analytical procedures of this method are long,which is not suitable for the analysis of large quantities of samples.Meanwhile,the determination range of this method is limited and only suitable for samples with sulfur mass fraction between 0.025%and 0.500%.In order to meet the needs of production and scientific research of titanium concentrate,an analytical method for the determination of sulfur in titanium concentrate by high frequency furnace combustion infrared absorption was established.The test conditions were optimized,including dosage of sample,type and dosage of flux for combustion.The optimum analytical determination conditions were obtained as follows:0.40 g of sample was transferred into a crucible;then 0.5 g of tin particles,0.3 g of pure iron particles and 1.3 g of tungsten particles were added as flux.The calibration curve of sulfur was prepared sectionally using certified reference materials of titanium concentrate.The determination range of mass fraction of sulfur was 0.0048%-2.76%.The limit of quantification was 0.0006%,which could fully meet the determination results of existing titanium concentrate.The titanium concentrate samples with sulfur mass fraction of 0.0092%-1.51%were determined according to the experimental method.The relative standard deviation(RSD,n=8)of determination results were between 0.33%and 1.8%.The found results were consistent with those obtained by barium sulfate gravimetric method.The spiked recoveries for the low-sulfur samples were between 90%and 105%.