论文部分内容阅读
在H3PO4介质中,甲醛对溴酸钾氧化结晶紫的褪色反应有催化作用,基于此建立了催化光度法测定甲醛的新方法。讨论了H3PO4用量、结晶紫用量、KBrO3用量、反应温度及反应时间的影响,确立了最佳反应条件。在选择的条件下,该方法的线性范围为0.11~1.12 mg/L,检出限为4.5×10-2mg/L。该方法用于啤酒中甲醛的测定,测定结果的相对标准偏差(RSD)均小于5%(n=5),回收率为95.2%~109.1%,能满足啤酒中甲醛的测定要求。
In H3PO4 medium, the catalytic effect of formaldehyde on the fading reaction of crystal violet with potassium bromate is catalyzed, and a new method of catalytic spectrophotometric determination of formaldehyde is established. The effects of H3PO4 dosage, crystal violet dosage, KBrO3 dosage, reaction temperature and reaction time were discussed. The optimal reaction conditions were established. Under the selected conditions, the linear range of this method was 0.11-1.12 mg / L with the detection limit of 4.5 × 10-2 mg / L. The method was applied to the determination of formaldehyde in beer. The relative standard deviations (RSDs) of the determination were less than 5% (n = 5) and the recoveries ranged from 95.2% to 109.1%. The method met the determination requirements of formaldehyde in beer.