【摘要】 利用在硫酸介质中铬(Ⅵ)能够灵敏地氧化玫瑰桃红R而使之褪色,将该法与流动注射自动进样技术联用,建立了快速测定铬(Ⅵ)的流动注射-褪色光度法。考察了流速、进样环体积、反应圈长度、反应温度、反应酸度、玫瑰桃红R浓度等对铬(Ⅵ)测定的影响。铬(Ⅵ)质量浓度在0.10～10.0mg/L范围内与吸光度呈线性关系,相关系数为0.9996,相对标准偏差(RSD)为1.4%(ρ=2.0mg/L,n=11)。方法应用于电镀废水中铬(Ⅵ)的测定,回收率在98%～104%之间。结果同国家标准方法的测定结果相一致。更多还原

【Abstract】 On the basis of the fading reaction of bordeaux red with chromium (Ⅵ) in sulfuric acid medium, a fading spectrophotometric method combined with flow injection technology has been developed for the determination of chromium (Ⅵ) . Experimental parameters were examined, including flow rate, volume of sampling loop, length of the reaction coil, reaction temperature, reaction acidity, and concentration of bordeaux red. The chromium (Ⅵ) concentration in the range of 0.10-10.0 mg/L is linear with its absorbance with correlation coefficient of 0.999 6.The relative standard deviation (RSD) is 1.4% for 2.0 mg/L chromium (Ⅵ) (n=11).The method has been successfully applied to the determination of chromium (Ⅵ) in electroplating wastewater, and the recoveries were between 98% and 104 %. The results were consistent with those obtained by national standard method.更多还原