ICP-AES法测定磷矿浆烟气脱硫剂固液相中硫含量的研究

Determination of Sulfur in Solid and Solution of Phosphate Ore Pulp Flue Gas Desulfurization Agent with ICP-AES

SO2是大气主要污染物,与雾霾的形成有直接关系,烟气脱硫是保护环境、减少雾霾的有效措施。磷矿浆法烟气脱硫是一种以磷矿浆为吸收剂的新型脱硫方法。采用电感耦合等离子体原子发射光谱(ICPAES)法测定磷矿浆烟气脱硫剂固液相(磷矿粉、磷矿浆脱硫液和脱硫渣)中硫含量。在选定了较灵敏的硫分析线后,探讨了ICP光谱仪工作条件对分析结果的影响,同时研究了样品预处理方法以及共存元素对硫测定结果的影响。分别用三种不同的方式对磷矿粉、磷矿浆脱硫液和脱硫渣样品进行前处理,确保样品溶解完全。选用181.973nm光谱线为分析线,避免共存元素的光谱干扰。选择仪器的入射功率为1 300W,观测高度为12mm,雾化气流量为0.65L·min-1,泵进样量为1.5mL·min-1。在光谱仪最佳分析条件下,利用该方法测定磷矿粉、磷矿浆脱硫液及脱硫渣中硫的含量,其检出限为0.000 38%,加标回收率在89.5%~104.5%之间,相对标准偏差(RSD)≤2.30%,同时与硫酸钡重量法进行对比实验,结果基本吻合,相对偏差≤3.88%,该方法简便快捷,精密度和准确度较高,适用于磷矿浆脱除烟气SO2的科研及生产中。

Sulfur dioxide is the main air pollutant.It is directly related to the formation of haze.Flue is gas desulfurization.The primary measure of protecting the environment and reducing haze.Phosphate ore pulp flue gas desulfurization is a new desulfurization method in which desulfurization agent is phosphate ore pulp.The concentration of sulfur in solid and solution（phosphate rock,desulfurization liquid of phosphate rock and desulfurization slag）of phosphate ore pulp flue gas desulfurization agent were determined with Inductively Coupled Plasma Atomic Emission Spectrometry（ICP-AES）.By choosing a more sensitive analytical line of sulfur,the effects of operating conditions of the ICP spectrometer on the analysis results were investigated,at the same time,the sample preparation methods and coexisting ions which impact on determination results of sulfur was also considered.Phosphate rock,desulfurization liquid of phosphate rock and desulfurization slag were treated in three different ways to make sure the sample dissolved completely.181.973 nm spectral line was chose as analytical line to avoid spectral interference of coexisting element.The incident power of 1 300 W,with observation height of 12 mm,the nebulizer gas flow of 0.65L·min-1 and the pump flow rate of 1.5mL·min-1 were selected.Under the optimum analytical conditions of spectrometer,the method was used for the determination of sulfur in phosphate rock,desulfurization liquid of phosphate rock and desulfurization slag with the detection limit of 0.000 38%,recoveries between 89.5% and 104.5%,and relative standard deviation（RSD≤2.30%）.By comparing the results of barium sulfate gravimetric method,the findings were basically consistent with the relative deviation≤3.88%.In conclusion,the method is simple and efficient,with high precision and accuracy,which can be used for research and routine production in phosphate ore pulp flue gas desulfurization.