论文部分内容阅读
介绍了试剂的合成方法、结构特点及与铌的显色条件,提出了测定钢中微量铌的分析方法。该试剂合成分为两步:首先将间氨基苯磺酸重氮化,后与变色酸偶联,生成单偶氮化物;其次,把426酸重氮化后与上述单偶氮化物偶联,生成双偶氮物,即2-(2-羟基-3-磺酸-5-硝基苯偶氮)-7-(3-磺基苯偶氮)-1.8-羟基萘-3.6-二磺酸,简称为硝基磺酚-M。该试剂为暗红色粉末,易溶于水,在碱性溶液中为深兰色,浓硫酸中为绿色,其水溶液在空气中长期稳定,但遇强还原剂能使其褪色。试剂与铌显色,在0.5～3N盐酸或0.5～5N硝酸中为最好,与铌生成1:1兰色络合物。最大吸收峰为620mm,试剂为540nm,对比度为80nm,克分
The synthesis method, structural characteristics and the conditions for the color development of niobium are introduced. An analytical method for the determination of trace niobium in steel is proposed. The synthesis of the reagent is divided into two steps: firstly, diazotization of m-aminobenzene sulfonic acid and then coupling with chromotropic acid to form monoazo compound; secondly, coupling the 426 acid diazotization to the monoazo compound, Azo compounds such as 2- (2-hydroxy-3-sulfonic acid 5-nitrophenylazo) -7- (3-sulfophenylazo) -1 .8-hydroxynaphthalene-3,6-disulfonic acid , Referred to as nitrosulphon-M. The reagent is a dark red powder, soluble in water, dark blue in alkaline solution and green in concentrated sulfuric acid. Its aqueous solution is long-term stable in the air, but strong reducing agent can make it fade. Reagents and niobium color, 0.5 ~ 3N hydrochloric acid or 0.5 ~ 5N nitric acid is the best, and niobium to generate 1: 1 blue complex. The maximum absorption peak is 620 mm, reagent is 540 nm, contrast is 80 nm, g fraction