铜(Ⅱ)-氯酸钾-盐酸苯肼-α-萘胺体系催化动力学光度法测定痕量铜  

Catalytic kinetic spectrophotometric determination of trace copper using copper(Ⅱ)-potassium chlorate-phenylhydrazine hydrochloride-α-naphthylamine system

作　　者：任健敏[1] 林壮森[2] 彭珊珊[1] 

机构地区：[1]韶关学院化学系,广东韶关512005 [2]广东工业大学轻工化工学院,广东广州510090

出　　处：《冶金分析》2006年第5期81-83,共3页Metallurgical Analysis

摘　　要：基于铜(Ⅱ)催化氯酸钾氧化盐酸苯肼继而与α-萘胺偶合显色的反应,建立了催化动力学光度法测定痕量铜的新方法。通过正交试验得到测定痕量铜的最佳条件。在合适条件下,催化和非催化反应吸光度差(△A)与反应时间(t)呈线性关系,其回归方程为△A=2.8571+55.087t,r=0.9985;表观速率常数为k=8.2×10-2/s,为准零级反应;表观活化能为92.1kJ/mol,方法的线性范围为0～0.08μg/mL,检出限为6.26×10-10g/mL。大多数离子无干扰,Fe3+干扰可加入NaF掩蔽。用于管网水中痕量铜的测定,回收率96.8%和98.8%。A new catalytic spectrophotometric method for the determination of trace copper has been established. It is based on the fact the copper（Ⅱ）can catalyze the oxidation of phenylhydrazine hydrochloride by potassium chlorate and then the oxidation products are coupled with α-naphthylamine. The optimum conditions of the catalytic reaction are studied by 4 factors 3 horizontal orthorhombic experiments. Under the suitable conditions, the absorbance difference（ △A ） between catalytic and non-catalytic reaction is linear with time（ t ）. The linear regression equation is △A = 2. 857 1 ＋ 55. 087 t, r= 0. 998 5. The constant of rate is k = 8.2 × 10^-2/s. The catalytic reaction is a pseudo zero order reaction. The apparent activation energy of the catalytic reaction is found to be 92.1 kJ/mol. The linear range is 0 -0.08 μg/mL,and the detection limit is 6.26 ×10^- 10 g/mL. Major ions do not interfere expect for Fe^3＋ （masking with NaF）. The method has been applied to the determination of Cu（Ⅲ） in tap water samples with the recovery of 96.8 % and 98.8 %.

关 键 词：正交试验 催化动力学 分光光度法 痕量铜 

分 类 号：O657.32[理学—分析化学]