流动注射分光光度法测定皮革制品中的甲醛

Spectrophotometric Determination of Formaldehyde in Leather Samples with Chromotropic acid by Flow Injection Analysis

研究了流动注射变色酸分光光度法测定皮革制品中的甲醛。与传统的变色酸光度法相比，该方法具有灵敏度更高，干扰更少的特点。在0．4mol／L硫酸介质中，甲醛与变色酸在85℃左右形成络合物，该络合物在390nm有最大吸收峰，且能稳定存在至少96h。详细考察了各种测试条件如萃取剂、萃取时间、显色时间、反应温度、反应时间等对甲醛测定结果的影响，优化了反应的化学因素和流动注射系统反应条件。该方法的检出限和线性范围分别为0．1p,g／L（3σ）和50—1000μg／L，相对标准偏差为0．56％（连续注射500μg／L甲醛标液11次）。该方法成功用于皮革制品或者皮质材料中的甲醛的测定。

A highly sensitivity and relatively interference-free spectrometric method is described for the determination of formaldehyde in leather, which is based on its reaction with chromotropic acid in the medium of 0. 4 mol/L sulfuric acid medium to form a complex. The absorbance of the complex was measured spectrophotometrically at 390 nm, the stabilization of the complex was not less than 96 h. The chemical factors and FIA vailables affecting the system were also examined, including various solvent, reaction time, and so on. The detection limit was 0.1 μg/L calculated from three times the average background noise. The linearity concentration range of the correlation curve was from 0.05 to 10 mg/L of standard solutions. And the relative standard deviation was 0.6% （n = 11 ） obtained by injecting 500 μg/L standard formaldehyde solution. The proposed method was successfully applied to determine formaldehyde in leather.