紫外分光光度法直接测定常量硫酸根  

Direct Determination of Macro-Amounts of Sulfate by UV Spectrophotometry

作　　者：詹文毅[1] 江国庆[1] 姜国民[1] 葛存旺[1] 田澍[1] 李建华[1] 

机构地区：[1]南通大学化学化工学院,南通226019

出　　处：《理化检验（化学分册）》2016年第2期159-162,共4页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：南通大学自然科学基金资助项目(12Z027);南通市应用研究计划资助项目(BK2014071)

摘　　要：提出了紫外分光光度法直接测定常量硫酸根。将脱硫石膏样品以盐酸溶解并使其中的硫酸根沉淀为硫酸钡,通过磷酸钠置换使硫酸根全部溶出,在紫外波段193,210nm处分别测定吸光度。硫酸根的线性范围为0.002~0.01mol·L-1,方法的检出限（3s/k）为3.2×10-4 mol·L-1。方法用于脱硫石膏样品的分析,测定结果与硫酸钡重量法测定值相符,测定结果的相对标准偏差（n=5）在0.18%~0.23%之间。A method of UV spectrophotometry for the direct determination of macro-amounts of sulfate was proposed. The desulfurized gypsum sample was dissolved with hydrochloric acid and the sulfate ion in the solution was precipitated as barium sulfate. Sodium phosphate was added for substitution and full dissolution of sulfate was achieved. Values of ultraviolet absorbances were measured at 193 nm and 210 nm separately. Linearity range of sulfate ion was found between 0. 002 mol · L-1 and 0. 01 mol · L-1 with detection limit （3s/k） of 3.2 × 10-4 mol · L 1. The proposed method was applied to the analysis of desulfurized gypsum sample, giving results in consistency with those obtained by barium sulfate gravimetric method, giving values of RSD＇s （n=5） in the range of 0. 18%-0. 23%.

关 键 词：紫外分光光度法 常量分析 硫酸根 

分 类 号：O657.32[理学—分析化学]