CN101576482B

CN101576482B - Method for analyzing trace tin in selenium

Info

Publication number: CN101576482B
Application number: CN2009100401468A
Authority: CN
Inventors: 戴凤英; 刘天平
Original assignee: Guangzhou Research Institute of Non Ferrous Metals
Current assignee: Guangzhou Research Institute of Non Ferrous Metals
Priority date: 2009-06-10
Filing date: 2009-06-10
Publication date: 2011-05-18
Anticipated expiration: 2029-06-10
Also published as: CN101576482A

Abstract

The invention relates to a method for analyzing trace tin in selenium, which is characterized by comprising: adding a selenium sample into concentrated nitric acid and concentrated hydrochloric acid, and heating and dissolving the selenium sample; adding water into the mixture, adding the concentrated hydrochloric acid into the mixture, and heating the mixture until boiled; adding hydroxylamine chloride and an ascorbic acid into the mixture, stirring the mixture, standing the mixture in a boiled water bath, cooling the mixture, and using water to drive the obtained solution to have a constant volume; adding a mixture of a sulfuric acid and water with the proportion of 1:1 into one part of the solution, heating the mixture until white smoke is just emitted, and cooling the mixture; and adding a mixed solution of 50 g/L thiourea and 50 g/L ascorbic acid into the obtained solution, using water to drive the obtained solution to have a constant volume, placing the obtained solution, taking a mixture of the sulfuric acid and the water with the proportion of 1:99 as current carrier and a potassium borohydride solution as a reducing agent, and using an atomic fluorescence spectrometer to measure the mass concentration of tin. The method has good substrate separation effect, small selenium residue amount, high measurement sensitivity, simple and convenient operation and accurate result,does not use organic reagent which is harmful to the human body, and is suitable for measuring the tin content of between 0.0002 and 0.01 percent in the selenium.

Description

The analytical approach of trace tin in a kind of selenium

Technical field

The present invention relates to a kind of chemical analysis method, particularly a kind of metallic element chemical analysis method.

Background technology

Selenium is the important foundation material of making semiconductor, cooling module, photovalve etc., and the purity of selenium has very big influence to the physical property of making device.In the common pure selenium, except that containing 0.0002～0.01% trace tin, the copper that also contains trace, mercury, arsenic, antimony, tellurium, iron, plumbous, nickel, bismuth, magnesium, aluminium, silicon, impurity elements such as boron, Determination of Microamount of Tin adopts existing industry standard YS/T226.3-1994 chemical analysis method usually in the selenium at present, its method principle is: use nitric acid, sulfuric acid decomposes selenium, under 320 ℃ of conditions of volatilization stove, the selenium volatilization is eliminated, in the 0.5mol/L sulfuric acid medium, tin and phenylfluorone-bromohexadecane base Trimethylamine generates red complex, measures its absorbance in wavelength 510nm place.This method sample pre-treatments adopts selenium with SeO ₂The form volatilization is removed with element tin to be measured and is separated, and will produce selenium steam in the processing procedure, and regularly use organic reagent in follow-up Spectrophotometry for Determination, is detrimental to health contaminated environment.

Summary of the invention

In order to overcome the deficiency of industry standard method, the purpose of this invention is to provide a kind of analytical approach, this method sample good separating effect, the residual quantity of selenium is little, do not use harmful organic reagent, adopt the hydride Generation-Atomic Fluorescence Spectrometry to measure, highly sensitive, easy and simple to handle, the result is accurate.

Technical scheme of the present invention is: take by weighing 0.50～1.00g selenium sample, add 2～5mL red fuming nitric acid (RFNA) and 20mL concentrated hydrochloric acid, heating for dissolving; Adding water to volume is 60mL, adds 20～30mL concentrated hydrochloric acid again, is heated to and boils; Add 6～10g hydroxylamine chloride and 2g ascorbic acid, stir, place boiling water bath to leave standstill 1.5～2h, after the cooling, get the solution with water constant volume; Divide and get 5～20mL solution, add 1: 1 sulfuric acid of 1mL: water is heated to and just emits white cigarette, cooling; Add 4～8mL 50g/L thiocarbamide: 50g/L ascorbic acid mixed solution, the water constant volume is placed 15～30min, and with 1: 99 sulfuric acid: water was made current-carrying, and the solution of potassium borohydride of 20～30g/L is a reductive agent, measures the mass concentration of tin with atomic fluorescence spectrometer.

Embodiment

The sample of embodiment is a pure selenium, is that the purity that made through further purifying by cathode copper, the plumbous earth of positive pole and the comprehensive selenium raw material that reclaims of waste materials such as the flue dust of sulfuric acid plant, sour mud is at the selenium more than 99%.Choose two kinds of different samples, be respectively sample 1# and 2#, each embodiment by same procedure measure sample 1# and 2# selenium each once.

Embodiment 1

Take by weighing the 0.50g sample and place 250mL beaker (doing blank test) in company with sample, wetting with low amounts of water, add the 2mL red fuming nitric acid (RFNA), the low-grade fever dissolved samples.Add the 20mL concentrated hydrochloric acid, heating makes sample dissolution, takes off cold slightly.Adding water to volume is 60mL, adds the 25mL concentrated hydrochloric acid again, is heated to and boils.Take off coldly slightly, add 7g hydroxylamine chloride, 2g ascorbic acid, stir and make the selenium precipitation separate out and condense.Place boiling water bath to leave standstill 2h in beaker, after the cooling test solution is changed in the 100mL volumetric flask, the simple substance selenium of cohesion can be stayed in the beaker, is diluted to scale with water, mixing.

Branch is got the 20mL test solution and is placed the 150mL beaker, adds 1mL1: 1 sulfuric acid: water, and be heated to and just emit the white cigarette of sulfuric anhydride, take off cooling.Add low amounts of water and boil, change over to after the cooling in the 50mL volumetric flask, add the 6mL50g/L thiocarbamide: 50g/L ascorbic acid mixed solution, be diluted with water to scale, mixing is placed 20min.Sulfuric acid with 1: 99: water is made current-carrying, and the 25g/L solution of potassium borohydride is a reductive agent, measures its fluorescence intensity on atomic fluorescence spectrometer, deducts the fluorescence intensity in company with the sample blank testing liquid, calculates the mass concentration of tin with calibration curve method.

Embodiment 2

Take by weighing the 1.00g sample and place 250mL beaker (doing blank test) in company with sample, wetting with low amounts of water, add the 3mL red fuming nitric acid (RFNA), the low-grade fever dissolved samples.Add the 20mL concentrated hydrochloric acid, heating makes sample dissolution, takes off cold slightly.Adding water to volume is 60mL, adds the 30mL concentrated hydrochloric acid again, is heated to and boils.Take off coldly slightly, add 8g hydroxylamine chloride, 2g ascorbic acid, stir and make the selenium precipitation separate out and condense.Place boiling water bath to leave standstill 1.5h in beaker, after the cooling test solution is changed in the 100mL volumetric flask, the simple substance selenium of cohesion can be stayed in the beaker, is diluted to scale with water, mixing.

Branch is got the 10mL test solution and is placed the 150mL beaker, adds 1mL1: 1 sulfuric acid: water, and be heated to and just emit the white cigarette of sulfuric anhydride, take off cooling.Add low amounts of water and boil, change over to after the cooling in the 50mL volumetric flask, add 4mL 50g/L thiocarbamide: 50g/L ascorbic acid mixed solution, be diluted with water to scale, mixing is placed 25min.Sulfuric acid with 1: 99: water is made current-carrying, and the 30g/L solution of potassium borohydride is a reductive agent, measures its fluorescence intensity on atomic fluorescence spectrometer, deducts the fluorescence intensity in company with the sample blank testing liquid, calculates the mass concentration of tin with calibration curve method.

Embodiment 3

Take by weighing the 1.00g sample and place 250mL beaker (doing blank test) in company with sample, wetting with low amounts of water, add the 4mL red fuming nitric acid (RFNA), the low-grade fever dissolved samples.Add the 20mL concentrated hydrochloric acid, heating makes sample dissolution, takes off cold slightly.Adding water to volume is 60mL, adds the 20mL concentrated hydrochloric acid again, is heated to and boils.Take off coldly slightly, add 9g hydroxylamine chloride, 2g ascorbic acid, stir and make the selenium precipitation separate out and condense.Place boiling water bath to leave standstill 2h in beaker, after the cooling test solution is changed in the 100mL volumetric flask, the simple substance selenium of cohesion can be stayed in the beaker, is diluted to scale with water, mixing.

Branch is got the 5mL test solution and is placed the 150mL beaker, adds 1mL1: 1 sulfuric acid: water, and be heated to and just emit the white cigarette of sulfuric anhydride, take off cooling.Add low amounts of water and boil, change over to after the cooling in the 50mL volumetric flask, add 8mL 50g/L thiocarbamide: 50g/L ascorbic acid mixed solution, be diluted with water to scale, mixing is placed 30min.Sulfuric acid with 1: 99: water is made current-carrying, and the 20g/L solution of potassium borohydride is a reductive agent, measures its fluorescence intensity on atomic fluorescence spectrometer, deducts the fluorescence intensity in company with the sample blank testing liquid, calculates the mass concentration of tin with calibration curve method.

Table 1 is result's contrast of measuring tin in the sample with method of the present invention and industry standard YS/T226.3-1994 analytical approach.As can be seen from Table 1, this law result and rower methods and results basically identical.

The result that table 1 is measured trace tin in the selenium compares

Because a large amount of matrix selenium produce seriously Determination of Microamount of Tin and disturb, therefore need to separate except that selenium.Table 2 has provided embodiment 2 behind the reduction separating step, and selenium amount remaining in the test solution is removed main element selenium the correlation data of the remaining selenium amount in back with adopting the industry standard method with the volatilization of SeO2 form in 320 ℃ of selenium volatilization stoves.By table 2 as seen, the separating effect of this law is better than the rower method.

The remaining selenium amount of table 2

Table 3 has provided the mark-on recovery test result of the inventive method, adds the tin standard of different amounts respectively in the 1# sample, measures by the method for embodiment 3.By table 3 as seen, method recovery of standard addition of the present invention is between 97.9～102.7%, accurately and reliably.

Table 31# sample mark-on recovery test

Table 4 has provided the Precision test result of method, presses the method for embodiment 2,1#, 2# sample is carried out 9 times respectively measure the relative standard deviation of computing method, the stability of investigation method and reappearance.Data presentation, the relative standard deviation of this law is less, and method is stable, favorable reproducibility.

The test of table 4 precision

Comprehensive above data as seen, method of the present invention be the residual quantity of a kind of matrix good separating effect, selenium little, do not use that harmful organic reagent, mensuration are highly sensitive, detection limit is less than 1 * 10 ^-9G/mL, easy and simple to handle, result accurately, the analytical approach of trace tin in the selenium of favorable reproducibility.Be applicable to and measure in the pure selenium 0.0002～0.01% tin content.

Claims

1. the analytical approach of trace tin in the selenium is characterized in that taking by weighing 0.50～1.00g selenium sample, adds 2～5mL red fuming nitric acid (RFNA) and 20mL concentrated hydrochloric acid, heating for dissolving; Adding water to volume is 60mL, adds 20～30mL concentrated hydrochloric acid again, is heated to and boils; Add 6～10g hydroxylamine chloride and 2g ascorbic acid, stir, place boiling water bath to leave standstill 1.5～2h, after the cooling, get the solution with water constant volume; Divide and get 5～20mL solution, add 1: 1 sulfuric acid of 1mL: water is heated to and just emits white cigarette, cooling; Add 4～8mL 50g/L thiocarbamide: 50g/L ascorbic acid mixed solution, the water constant volume, place 15～30min, sulfuric acid with 1: 99: water is made current-carrying, the solution of potassium borohydride of 20～30g/L is a reductive agent, on atomic fluorescence spectrometer, measure its fluorescence intensity, deduct fluorescence intensity, calculate the mass concentration of tin with calibration curve method in company with the sample blank testing liquid.