论文部分内容阅读
介绍了新试剂3-羟基1-(2-氯-4-硝基苯基)-3-苯基三氮烯(HCNPPT)的合成及质谱鉴定结果。提出了在十二烷基硫酸钠(SDS)和聚乙烯醇(PVA)存在下用HCNPPT分光光度测定高含量镁的方法。测定的最佳碱度为0.2mol/L NaOH介质,于25mL溶液中含4.0—6.0mL2×10~(-4)mol/L HCN PPT、1.5—2.4mL 2%PVA和1.0—3.0mL 2.5%SDS时可获得满意的结果。测定以试剂空白为参比在530nm处进行,比尔定律适用范围为0.08—0.48mg/mL Mg(Ⅱ),显色后20—90min内吸光度值不变,方法的选择性好,测定4mgMg(Ⅱ)时40mgN~+、K~+、Cs~+、Sr~(2+)、Ba~(2+)、10mgCl~-,6mgSO_4~(2-)、EDTA,0.4mgFe~(2+)、SiO_2和0.1mgCa~(2+)、Al~(3+)不干扰。用于测定菱镁矿中的镁,结果良好。
The new reagent 3-hydroxy 1- (2-chloro-4-nitrophenyl) -3-phenyl-triazene (HCNPPT) was synthesized and identified by mass spectrometry. A method of spectrophotometric determination of high levels of magnesium with HCNPPT in the presence of sodium dodecyl sulfate (SDS) and polyvinyl alcohol (PVA) has been proposed. The optimum alkalinity was 0.2mol / L NaOH medium, containing 4.0-6.0mL 2 × 10 -4 mol / L HCN PPT, 1.5-2.4mL 2% PVA and 1.0-3.0mL 2.5% SDS can get satisfactory results. The determination of reagent blank at 530nm, Beer’s Law range of 0.08-0.48mg / mL Mg (Ⅱ), after 20-90min color expression unchanged, the selectivity of the method, the determination of 4mgMg (Ⅱ (2 +), 10 mgCl ~ -, 6 mg SO_4 ~ (2 -), EDTA, 0.4 mg Fe ~ (2 +), And 0.1mgCa ~ (2 +), Al ~ (3+) do not interfere. For the determination of magnesium in magnesite, the result is good.