流动注射化学发光测定乙醛的研究

Study on Determination of Acetaldehyde by Chemiluminescence with Flow Injection

本文研究了应用Ｇａ（没食子酸）－Ｈ２Ｏ２－ＯＨ－化学发光体系、流动注射技术测定乙醛的条件，如反应介质及其ｐＨ值，Ｇａ及Ｈ２Ｏ２溶液的浓度，温度、试液混合次序与化学发光强度的关系等，选择了流动注射系统的若干参数。所拟定的方法测定乙醛的浓度范围为每ｍＬ１．７×１０－３～４．４×１０－７ｇ，相对标准偏差为１．８％（用２×１０－５ｇ／ｍＬ乙醛溶液进行１１次平行测定），检出限为每ｍＬ３．１×１０－８ｇ，采样频率为１２０次／ｈ。该法用于有机化工厂废水及酒精中乙醛的测定，结果令人满意。

Conditions of determination of acetaldehyde with Ga H 2O 2 OH - chemiluminescence system and flow injection technique ,including the effects of media,pH,concentration of Ga and H 2O 2,temperature and the order of reagent addition on the maximum of chemiluminescence intensity were selected.And the flow system was optimized.Chemiluminescence intensity is linearly proportional to acetaldehyde concentration from 4.4×10 -7 to 1 7×10 -8 g per mL.Using the optimized system,a satisfactory method for acetaldehyde determination in waste water and alcohol was developed with a mean error of 1.8% (using 2×10 -8 g per mL acetaldehyde solution with 11 replicates),a detection limit of 3.1×10 -8 g per mL and a sampling rate of 120 times per hour.