Method for pretreating sample during detection of impurities in high-purity aluminum metaphosphate by using plasma spectrum method

Abstract

The invention discloses a method for pretreating a sample during detection of impurities in high-purity aluminum metaphosphate by using a plasma spectrum method, which belongs to the technical field of detection of trace impurity elements, and is used for solving the problems that the impurities are easily introduced, the interference is great and the sample introduction flow fluctuates to influence the accuracy in the conventional method. The method mainly comprises the following steps: (1) weighing a solid-state high-purity aluminum metaphosphate powder sample, adding the sample into a plastic closed container, adding a concentrated hydrochloric acid solution and fully contacting aluminum metaphosphate with the acid solution, closing the plastic closed container, and preserving the digestion temperature to be 180-200 DEG C for 4-5 hours; and (2) if clarification is achieved, cooling to room temperature, transferring the solution into a volumetric flask, diluting the solution to achieve the scales, and shaking uniformly, thereby obtaining an aluminum metaphosphate sample solution; if clarification is not achieved, adding a proper amount of hydrofluoric acid, stirring, standing, diluting the solution to achieve the scales after the solution is clarified, shaking uniformly, thereby obtaining the aluminum metaphosphate sample solution. The method disclosed by the invention has the characteristics of relatively few reagents, low salinity and low spectral background and is mainly used for measuring the trace impurity elements contained in high-purity aluminum metaphosphate.

Description

technical field [0001] The invention belongs to the technical field of detection of trace impurity elements. In particular, it relates to a plasma spectrometry method, which is a method for pretreating samples when detecting high-purity aluminum metaphosphate impurities. Background technique [0002] Inductively coupled plasma-atomic emission spectrometry (ICP-AES) is now commonly used equipment. It has high analytical sensitivity, wide linear range, and low background, and can effectively determine trace elements in aqueous solutions. [0003] Existing alkali fusion (dissolution) method prepares the method that adopts plasma spectrometry to measure the aluminum metaphosphate impurity solution sample as follows: the solid aluminum metaphosphate sample powder is placed in the silvery or polytetrafluoroethylene container, then into the container Add sodium hydroxide or potassium hydroxide, heat until it is completely dissolved, then add strong acid to neutralize the acidific...

AI Technical Summary

Problems solved by technology

[0004] The disadvantages of using the aluminum metaphosphate sample solution prepared by this alkali dissolution (or alkali fusion) method to measure trace impurities by plasma spectrometry are: 1. The method requires a large amount of sodium hydroxide or potassium hydroxide; 2. The sample The solution contains a higher concentration of salt, which increases the background and interference in the plasma spectrometry

Moreover, the sampling system of the instrument is easily blocked, and the sampling flow rate fluctuates, resulting in poor repeatability of test results, and poor accuracy and precision.