Method for determining content of fluorine in fluorine-containing liquid during tantalum and niobium hydrometallurgical process

Abstract

The invention discloses a method for determining the content of fluorine in a fluorine-containing liquid during the tantalum and niobium hydrometallurgical process, which comprises the steps of preparing a lanthanum nitrate solution, and transferring the lanthanum nitrate solution to a potentiometric titration bottle for calibration; cleaning the pipeline of a potentiometric titrator with pure water, and then moistening the pipeline of the potentiometric titrator with the lanthanum nitrate solution, wherein the titration type is mv titration, the end point parameter is the first end point, theend point jump is middle, and the jump volume is 100.0mv / ml; adding a standard solution of fluorine into a titration cup, adding pure water, placing the solution in the potentiometric titrator for titration, recording the titration volume of lanthanum nitrate, and calculating the titer of lanthanum nitrate according to a formula 1; adding a sample solution into the titration cup, adding ammonia water, pure water and neutral red in sequence, adjusting the sample solution from yellow to red by a hydrochloric acid solution, then placing the solution in the potentiometric titrator for titration,recording the titration volume of lanthanum nitrate, and calculating the content of fluorine in the sample solution according to a formula 2. The method of the invention has the characteristics of high reproducibility, small relative standard deviation in measurement and high accuracy.

Description

technical field [0001] The invention belongs to the technical field of fluorine determination methods, and in particular relates to a method for determination of fluorine content in fluorine-containing liquids during tantalum-niobium hydrometallurgy. Background technique [0002] At present, the tantalum liquid, niobium liquid, tantalum neutralization mother liquid and niobium neutralization mother liquid involved in the fluorine-containing liquid in the tantalum and niobium hydrometallurgy process all contain high content of fluorine. For tantalum liquid, niobium liquid and tantalum neutralization mother liquid , Determination of fluorine content in niobium neutralization mother liquor, the industry generally uses fluorine ion selective electrode to measure its potential value, and then calculates the fluorine content in the solution by drawing the calculation formula generated by the standard curve, this method belongs to the analysis of low content fluorine method, the so...

AI Technical Summary

Problems solved by technology

[0002] At present, the tantalum liquid, niobium liquid, tantalum neutralization mother liquid and niobium neutralization mother liquid involved in the fluorine-containing liquid in the tantalum and niobium hydrometallurgy process all contain high content of fluorine. For tantalum liquid, niobium liquid and tantalum neutralization mother liquid , Determination of fluorine content in niobium neutralization mother liquor, the industry generally uses fluorine ion selective electrode to measure its potential value, and then calculates the fluorine content in the solution by drawing the calculation formula generated by the standard curve, this method belongs to the analysis of low content fluorine method, the method needs to dilute the solution thousands of times during the measurement process, resulting in large deviation of sample analysis data and poor accuracy

In addition, there is also thorium nitrate titration method for the determination of high content of fluorine. This method is not very suitable for the system in tantalum and niobium liquid. After the sample is treated, there is a white precipitate, and the color of the titration end point is not very obvious. ; and thorium nitrate, a radioactive substance, is used, and thorium nitrate has certain difficulties in procurement, storage, operation and subsequent treatment

Images