Study On The Determination Of Nb In Niobium-Tantalum Ore By Spectophotometry

With the continuous development of science and technology, using of the rareniobium and tantalum metal is used widely. The metals and alloys have been widelyapplied in the field of modern electronic industry, iron and steel, aerospace, chemicalindustry and other emerging industries. Therefore, accurate determination andextraction of niobium in niobium and tantalum ore are very important meaning.Spectrophotometry is sensitive,simple, accurate, rapid, operation, low runningcost, and wide applied method. However, the sample pretreatment step is required todetect niobium metal using spectrophotometry. Especially, the employed chromogenicand hyperchromic agents are toxic organic reagents, which are harmful. In this paper, amethod determination of niobium with high sensitivity, good accuracy, and simpleprocess was discussed by using low toxic reagents in the pretreatment progress.Main projects and results are as follow:1.Using of organic reagents for spectrophotometric determination of niobium, It isfound in the presence of sixteen alkyl pyridine bromide, tartaric acid as auxiliarycomplexing agent,and completed2,3,7-three hydroxy-9-salicylfluorone fluorone andchrome azurol S photometric determination of niobium target, this new method has highsensitivity and good accuracy compared with national standard method. This methodwas employed to test in real samples, and obtained satisfy results.Deep red compounds of2,3,7-three hydroxy-9-salicylfluorone and niobium（Ⅴ）have maximum absorption wavelength at560nm, Beer′s law is kept in the range of0.10⁶μgNb/25mL, complex apparent molar coefficient is1.44×10⁶L mol^-1 cm^-1the detection limit （3S/N） is0.092μ g mL^-1. Pink compounds of Chrome azurol S andNb（Ⅴ） have the maximum absorption wavelength at504nm, Beer′s law is kept in therange of0.07².4μgNb/25mL, complex apparent molar coefficient is2.1×10⁶L mol^-1 cm^-1the detection limit （3S/N） is0.064μ g mL^-1.2. The different processing methods for samples, affected differently the extractionof niobium in niobium and tantalum ore,using the roast-alkali fusion method forextraction of niobium in niobium and tantalum ore,Through the single factor experimentmethod to obtain the optimum extraction conditions of niobium in niobium andtantalum ore. niobium and tantalum ore:（80）, calcination temperature is600℃,roasting time is30min, alkalinity （Na₂O₂）is10times of the amount in the theory.3. Different kinds of anion exchange resin for separation system of niobium andtantalum elements have different effect. This paper research adsorption and separationof the metallic element niobium-tantalum in niobium-tantalum ore using four kinds of anion exchange resin such as D201, D202, D301, D303.D303resin has the best elutioneffect for niobium in niobium and tantalum ore, adsorbed completely on tantalum, noadsorption on niobium. Next is D301, but need to add EDTA for masking tantalum. Sothis paper uses D303anion exchange resin to elution niobium.4.The analysis results of Niobium in niobium tantalum ore are the same andsatisfactory with that of inductively coupled plasma atomic emission spectrometry. Thisspectrophotometry is economical, simple, and accurate and applied method widelycompared with other ways.