流动注射法-酸性铬蓝K在线快速测定制革用水的硬度

Acid chrome blue K rapid determination of the hardness of the water used for leather-making by flow injection analysis

本实验利用流动注射方法检测制革用水的硬度。在pH为10.0时酸性铬兰K与等摩尔混合的钙和镁标准溶液同时显色,等摩尔钙和镁分别与酸性铬蓝K形成1∶1配合物,两种配合物在波长468nm处存在一等摩尔吸收点。在最佳的条件下对制革用水的硬度进行检测。检测范围为0.3×10-5～2.9×10-5mol.L-1,y(mV)=53.063x+56.683(其中x为等摩尔钙和镁的浓度),相关系数R2=0.9987,加标回收率在92.38%～112.80%之间,精密度RSD=0.720%(n=12)。与国标EDTA滴定法检测结果对比,相对标准偏差RSD小于2.6%。操作方法简单可靠,可用于制革用水硬度的在线快速检测。

In this study,we used flow injection method detection water used for leather-making hardness. Under the conditions of pH 10.0, acid chrome blue K reacts with an equimolar mixture of calcium and magnesium standard solution at the same time. Equimolar calcium and magnesium standard solution react with acid chrome blue K to form a 1：1 complex. Two complexes have an equimolar absorption point at wavelength 468nm. Under the best conditions for the water used for leather-making hardness test, the detection range of 0. 3× 10-5 mol · L-1 - 2.9 × 10-5 mol · L-1 , a standard curve of the linear equation for y（mV） = 53.063x＋56. 683, the lin- ear correlation coefficient R2 = 0. 9987. The recoveries of standard addition between 92. 38% and 112. 80%, the precision RSD = 0. 720% （n= 12）. EDTA titration with GB test results differ less than 2.6%. The operation method is simple and reliable,and can be used in water used for leather-making hardness online fast detection.