催化光度法测定痕量钒(Ⅴ)

• 作 者: 张瑛 王翀煜 俞伟
• 机 构: 绍兴市质量技术监督检测院,绍兴县环境保护监测站,绍兴县环境保护监测站 312000,312000,312000
• 出 处: 化学分析计量
• 发表日期: 2001年06期
• 关键词: 催化 光度法 钒

研究了稀盐酸介质中钒(V)催化溴酸钾氧化1-氨基-8-萘酚-3,6-二磺酸一钠盐形成红色产物的指示反应,建立了催化光度法测定痕量钒(V)的新方法。在55℃下恒温反应55min,加EDTA抑制反应,同时以流水冷却,于λ_(max)=436nm处测定催化反应和非催化反应的吸光度A和A_0,钒(V)含量在0～20ng/25mL与△A呈良好的线性关系,测定的检出限为3.6×10~(-2)ng/mL。对24种共存离子进行了干扰试验,结果表明,该实验的干扰离子主要为Cu~(2+)、Fe~(2+)离子,可借助于碱沉淀分离予以消除,也可以用磺基水杨酸掩蔽,或采用732阳离子交换树脂分离。该法用于松针、桂园等试样的分析,结果比较准确。

The reaction of vanadium (V) in dilute hydrochloric acid with potassium bromate to oxidize 1-amino-8-naphthol-3,6-disulfonic acid monosodium salt to form a red product was studied. A catalytic spectrophotometric method for the determination of trace vanadium ) Of the new method. The reaction was heated at 55 ° C for 55 min, and EDTA was added to inhibit the reaction. While cooling with flowing water, the absorbances A and A_0 of the catalytic and non-catalytic reactions were measured at λ max = 436 nm, and the vanadium (V) And △ A showed a good linear relationship, the detection limit of 3.6 × 10 -2 ng / mL. The interference experiments of 24 kinds of coexisting ions were carried out. The results showed that the interference ions in this experiment are mainly Cu2 + and Fe2 +, which can be eliminated by alkali precipitation separation. Salicylic acid masked, or isolated using 732 cation exchange resin. The method is used for the analysis of pine needles and cinnamon fields. The results are accurate.