High Efficiency Determination of Tin in Tungsten Concentrate

In the process of tungsten concentrate smelting, the existence of tin will have a serious effect on the mechanical and physical properties of the tungsten concentrate. Therefore, according to the national standard, the quality standard of the product submitted in the process of selling tungsten concentrates is required to report the content of tin in the tungsten concentrate and to determine the content of tin.

For the determination of tin in tungsten concentrate, potassium iodate volumetric method is mainly used. Potassium iodate method is mainly in the early treatment of the sample. The simple zinc powder and salt are generally used to decompose, then the oxidizing agent will oxidize the tungsten blue, the potassium iodate method has the complicated determination process and the inaccurate measurement. Therefore, it is also very important to find a simple and low cost test method for rapid and accurate determination of tin content in tungsten concentrate.

A method of upgrading potassium iodate volumetric method has been put forward by scholars. Its main contents are as follows:

After mixing the tungsten concentrate and the compound melting agent, it was melted at 750~850°C at high temperature. After the cooling, the hydrochloric acid leaching solution was obtained by hot hydrochloric acid leaching at a concentration of 8 ~ 10mol/L at 70~90°C, the compound melting agent from the mass ratio of anhydrous borax, boric acid and zinc powder was 1.5 ~ 2.5:0.5 ~ 1.5:8 ~ 10.

In the hydrochloric acid leaching solution, potassium permanganate was oxidized to filtrate and separate tin solution.

The excess iron powder was added to the obtained tin solution, and the reduction reaction was heated in the isolated air environment. After the reduction reaction was completed, the cooling reaction liquid was reached to the room temperature. The reaction solution was titrated with potassium iodide standard solution as an indicator and the potassium iodide solution was titrated to the end point. The titration results were used to calculate the tin quality in tungsten concentrate. The amount is 100%.

The tungsten tin separation was fully realized by using special melting agent to melt and restore tungsten concentrate completely under appropriate temperature conditions, and then combined with hydrochloric acid leaching and potassium permanganate oxidation. In addition, the method not only solves the problem of the coagulation of the animal glue after the oxidation of potassium permanganate, which makes the filtration speed increase, the labor intensity is reduced, the analysis time is shortened, the separation of tungsten and tin is complete, the tin loss in the separation process is reduced, the interference of tungsten ion to the test is completely eliminated, the method can not be used for atomic fluorescence. Such as precision instruments, equipment cost, cost maintenance cost and so on are all reduced, suitable for various types of laboratory, rapid analysis, and also suitable for large quantities of samples, easy to use.

• < Prev
• Next >