单位波长吸光度改变量-分光光度法在检测环境样品中甲醛的应用 化学专业

单位波长吸光度改变量-分光光度法在检测环境样品中甲醛的应用摘 要：本文对以单位波长吸光度差量-分光法(ACW-S) ，对地表水进行检测，以研究此法对其甲醛检测的可行性，作出甲醛标准曲线，制备浊度模拟水样，筛选了拟合波长段。以浊度模拟水样及对应空白水样的准确度作为考量因素，筛选出(440～449)、(440～454)、(445～459)nm 等 3 组波长段，校准曲线线性范围介于 0.16～4.00mg /L，方法检出限在 0.026～0.052 mg /L 范围，直接测定实际样品所得加标回收率为 94.5%～106.0%(加标浓度为 0.200 mg /L 和 0.400 mg /L)。实验结果表明，ACW-S 法有利于减小样品浊度对甲醛检测结果的正干扰，与标准检测方法所用的单波长法相比，具有更高的准确度和精密度，且无需进行样品前处理。关键词：甲醛；乙酰丙酮；单位波长吸光度改变量；浊度；过滤；分光光度法Application of unit wave length absorbance change spectrophotometry in detecting formaldehyde in environmental samplesAbstract: the feasibility of detecting formaldehyde in surface water by unit wavelength spectrophotometry (ACW-S) was discussed, the standard curve of formaldehyde was made, turbidimetric simulated water was prepared, and the length of fitting wave was screened. By using turbidity to simuLate the accuracy of water samples and corresponding blank samples, 3 groups of wavelengths, such as (440~449), (440~454) and (445~459) nm, were selected. The linear range of the calibration curves ranged from 0.16 to 4.00mg /L, the detection limit was 0.026 to 0.052mg /L, and the recovery rate of the actual sample was 94.5% to 106.0% (the standard concentration is 0.200 and 0.400 mg/L). Experiments on actual water samples were carried out to analyze the results of ACW-S method for actual water samples. The ACW-S method is beneficial to reduce the positive interference of the sample turbidity to the test results of formaldehyde. Compared with the single wavelength method used by the standard detecti...