GOST 19709.1-83
GOST 19709.1−83 Tellurium of high purity. Method for the determination of sulphur (Change No. 1)
GOST 19709.1−83
Group B59
STATE STANDARD OF THE USSR
TELLURIUM OF HIGH PURITY
Method for the determination of sulfur
Tellurium of high purity. Method for determination of sulphur
AXTU 1709
Valid from 01.01.85
to 01.01.90*
_______________________________
* Expiration removed
Protocol N 4−93 inter-state Council
for standardization, Metrology and certification
(IUS N 4, 1994). — Note the manufacturer’s database.
DEVELOPED by the Ministry of nonferrous metallurgy of the USSR
PERFORMERS
V. P. Savraev, L. I. Zelensky, M. G. Sun, E. V. Lisitsyna, L. I. Maxi, E. V. Borovikova, N. Ryabova
INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
Member Of The Board Of A. P. Snurnikov
APPROVED AND put INTO EFFECT by Decision of the USSR State Committee on standards of 26 September 1983 N 4535
REPLACE GOST 19709.1−74
The Change N 1, approved and put into effect by the Decree of the USSR State Committee for standards from
Change No. 1 made by the manufacturer of the database in the text IUS N 5, 1989
This standard sets the polarographic method for the determination of sulphur (at a mass proportion of from 0,00002 to 0.03%) to the tellurium of high purity.
The method is based on the recovery of sulphur compounds to hydrogen sulphide, Stripping and absorption solution of alkali in the presence of hydroxylamine and Trilon B and polarography solution containing sulfide ions.
(Changed edition, Rev. N 1).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 22306−77 with the Supplement.
1.1.1. For the results analysis be the arithmetic mean of results of two parallel measurements.
1.1.2. Control of the correctness of the results of the analysis carried out by the method of standard addition.
Mass fraction of sulfur in the additive should be 100−200% of its content in the analyzed material.
The amount of additives is determined by difference 
and
— the results of the analysis of the sample
and the sample with the additive
, calculated as the arithmetic mean of two parallel definitions, the differences between them should not exceed the permissible values given in the standard.
The result of the analysis is considered correct if the value found additives different from the calculated values by no more than 
and
— the permissible discrepancy of the results of parallel measurements of sulfur in the sample
and the sample with the additive
.
Validation of the results of the analysis of a series of samples of tellurium perform /20 times a month, where
is the number of analysed samples of tellurium using the same reagents, solutions and equipment, but not less than once in
a month.
1.1.1,
1.1.3. Allowed the use of other equipment, materials, utensils and reagents, subject to obtaining the metrological characteristics not lower than specified in this standard.
(Added, Rev. N 1).
2. SAFETY REQUIREMENTS
2.1. Safety requirements — according to GOST 24977.1−81 and normative-technical documentation with the addition.
2.1.1. Used solutions and extractants with tellurium should drain into the collections.
Recycling and disposal of the compounds of tellurium should be as follows: the solution to precipitate out of the reaction flask is drained daily in a separate bottle, then after 2−3 weeks a precipitate of tellurium filtered off on paper filter, washed 2−3 times with water. Residue from the filter was dried in air, placed in a plastic bag and sent to the manufacturer for recycling.
3. APPARATUS, MATERIALS AND REAGENTS
Polarograph type AC-PPT-1 or the generic type PU-1.
The apparatus for making recovery and purification of the mixture (Fig.1). Flask capacity 3 DMis made of quartz glass or molybdenum.
Damn.1. Installation for the preparation of restorative mixtures
Installation for the preparation of restorative mixtures
Damn.1
Apparatus for recovery of sulfur and Stripping of hydrogen sulfide (Fig.2). Allowed the application of the inverse of the refrigerator and the receiver of any design that ensures the full absorption of sulfide ions.
Damn.2. Plant for recovery of sulfur and hydrogen sulfide Stripping of
Plant for recovery of sulfur and hydrogen sulfide Stripping of
1 — hot plate; 2 — reaction vessel with a reducing mixture; 3 — sections;
4 — receiver with an alkaline solution of hydroxylamine and Trilon B (spiral quartz nozzle,
welded to the outer side of the output tube back of fridge); 5 — reverse fridge;
6, 7 — bubbler with a solution of pyrogallol in caustic potash solution;
8 — bubbler with distilled water.
Damn.2
The unit with a closed coil and thermostat.
The electrolyzer with a remote anode.
Argon gas GOST 10157−79 or nitrogen according to GOST 9293−74.
Hydrochloric acid according to GOST 14261−77 and distilled; distilled mixed with deionized or double-distilled water in a volume ratio of 1:1 with the addition of 100 mg of potassium permanganate to 1 DMmixture. The first fraction volume of 300 cm
drop. For analysis use the second fraction with a volume of 400 cm
.
Nitric acid GOST 4461−77, double-distilled.
Potassium sulfate according to GOST 4145−74, twice recrystallized and calcined for 1 h at 500 °C.
Potassium hydroxide (caustic potash) according to normative-technical documentation, solution with a mass fraction of 25%.
Potassium iodide according to GOST 4232−74.
Distilled water GOST 6709−72, double-distilled (or svejeprokipachenna).
Potassium permanganate according to GOST 20490−75.
Potassium chloride according to GOST 4234−77, recrystallized, saturated solution.
Pyrogallol And a solution with a mass fraction of 25% potassium hydroxide solution.
Sodium posterolaterally (hipofosfit sodium) according to GOST 200−76.
Hydroxylamine hydrochloride according to GOST 5456−79, 2M solution.
Sodium sulfide according to GOST 2053−77.
Salt is the disodium Ethylenediamine — N, N, N', N' -tetraoxane acid (Trilon B) according to GOST 10652−73.
Mercury GOST 4658−73.
Bidistilled water: distilled water is poured into a flask with a capacity of 3 DM, pour about 1 g of granulated potassium hydroxide and potassium permanganate to the intense coloration and boil the solution. The first and third portions of the distillate is discarded, the second portion collected.
A. a solution of caustic Kali, 2M solution of 11.2 g of potassium hydroxide and 10 g Trilon B dissolved in 100 cmof double-distilled water. Prepare for 2 days before use.
B. a solution of Hydroxylamine hydrochloric acid, 2M solution of 13.9 g of hydroxylamine dissolved in 100 cmof double-distilled water.
Background electrolyte: 80 cmof solution A, 20 cm
of solution B and 150 cm
double-distilled water mixed in a day of use.
The recovery mixture in a flask with a capacity of 3 DM, equipped with a reflux condenser, making 444 g of potassium iodide, 150 g of sodium hypophosphite, pour 530 cm
of hydrochloric acid and 200 cm
of distilled water, stirred and boiled in a current of argon for 7−8 h. the Rate of argon purge should be 3−4 bubbles per 1 s. Argon pre-cleaned by passing through two bottles of Drexel with a solution of pyrogallol in caustic potash. During cooling from the recovery of the mixture should stand a variety of temperatures (Unallocated, indicates the lack of concentration of hydrochloric acid). The recovery mixture was decanted from the precipitate of salts and store in a flask with a glass stopper in the dark place.
Standard solutions of potassium sulfate.
Solution a: 0,0544 g of potassium sulfate dissolved in water. The solution was transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.
1 cmstandard solution A contains 0.1 mg of sulfur.
Solution B: 10 cmstandard solution And placed in a volumetric flask with a capacity of 100 cm
and then filled to the mark with water, prepared before use.
1 cmof a solution contains 0.01 mg of sulfur.
Standard solutions of sulfide sulfur.
Solution a: 0,0748 g of dried filter paper of sodium sulfide was placed in a volumetric flask with a capacity of 100 cmand dissolved in 20 cm
of the background electrolyte was adjusted to the mark with double-distilled water and stirred.
1 cmstandard solution A contains 0.1 mg of sulfur.
Solution B: 10 cmstandard solution And placed in a volumetric flask with a capacity of 100 cm
, made up to the mark and the background electrolyte and stirred.
1 cmof solution B of the standard contains 0.01 mg of sulfur.
A solution with a known content of sulphide sulphur: 0.2 cmof solution B is diluted with the background electrolyte in a graduated cylinder to 10 cm
and polarographic.
The sulfur content in polarographic solution is 0.2 mg/DM.
Solutions of sulfide sulfur is prepared on the day of use.
Reaction vessel: a cylinder made of PTFE or glass with a diameter of (40±10) mm and height (50±10) mm with a tight lid.
The quartz Cup with top diameter of (20±10) mm and height (20±5) mm according to GOST 19908−80*.
______________
* On the territory of the Russian Federation GOST 19908−90. — Note the manufacturer’s database.
Itestosterone acid according to GOST 4200−77.
Ammonia water according to GOST 24147−80.
Deionized water: distilled water is passed through a chromatographic column filled with cation exchanger KU-1 and the anion exchanger an-1 or similar.
Bromine according to GOST 4109−79, purified by distillation in a quartz apparatus and a three-time washing by shaking in a separating funnel with an equal volume of deionized or double-distilled water. The aqueous phase before discharge to the sewer is neutralized with an alkali.
The recovery mixture B: in a flask with a capacity of 3 DM, equipped with a reflux condenser, introduce 150 grams of sodium hypophosphite, pour 300 cm
of hydrochloric acid, 500 cm
itestosterone acid and 200 cm
of distilled water, stirred and boiled in a current of argon 6−8 h. the Rate of argon purge should be 3−4 bubbles per 1 s. Argon pre-cleaned by passing through two bottles of Drexel with a solution of pyrogallol in caustic potash solution. During cooling from the recovery of the mixture should stand a variety of temperatures (Unallocated, indicates the lack of concentration of hydrochloric acid). The recovery mixture was decanted from the precipitate of salts and store in a flask with a glass stopper in the dark place.
(Changed edition, Rev. N 1).
4. PREPARATION FOR ASSAY
4.1. In bubblers 6 and 7 (see the devil.2) pour a solution of pyrogallol in caustic potash. In bubbler 8 pour mediterreaneo or deionized water. Bubbler 8 connected to the reaction vessel 2 (quartz or glass) with vinyl chloride hoses. In the vessel 2 is filled once per shift 150 cmpre-treated recovery of the mixture A or B, and the receiver 4−10 cm
of the background electrolyte. Through refrigerator 5 pass cold water. Socket of the refrigerator and the socket tube 3 is slightly lubricated with phosphoric acid or spectral pure graphite. Through the installation of flow flow of argon at a rate of 2−3 bubbles per 1 s. If the speed of passage of bubbles of argon bubbler 6 and the receiver 4 are the same, the installation airtight.
Correctness of installation check a standard Stripping solution of sulphate sulphur. For this restoration the mixture is boiled for 1 h for further purification from sulfur. The recovery mixture was cooled, then, in the receiver 4 pour 10 cmof the background electrolyte, and a thin section of the fridge with the help of pipette into the reaction flask 2 are administered 0.2 cm
of a solution of potassium sulfate. The sulfide was removed within 40 min after switching on the tiles. Then the solution from the receiver poured into electrolyzer with a remote anode (anode compartment pre-filled with mercury at 2 mm above the level of platinum contact, a saturated solution of potassium chloride to the brim and closed with a stopper) and polarographic sulfide ions in the half-wave potential of minus 0.8 V relative to the saturated calomel electrode. The anode compartment of the electrolytic cell need daily fill with fresh saturated solution of potassium chloride.
The height of the peak on polarogram solution in the receiver is compared with the peak height of the solution is 0.2 mg/lof sulfide sulfur. The difference of the heights of peaks of both solutions should not exceed 10%. If the difference is greater and the solution in the receiver gives lower peaks, it is necessary to wash out the refrigerator deionized or double-distilled water and repeat the assay.
If the solution in the receiver gives a much higher peaks, we tested the correction in the reference experiment, as indicated in claim 4.2.
(Changed edition, Rev. N 1).
4.2. For the newly assembled unit are checking the purity of the recovery of the mixture and carrier gas (amendment in the reference experiment). For this recovery through boiling, the mixture was passed argon for 30 min. the Amendment reference experiment (in units of micrograms of sulfur in 10 cmof solution) are measured against the peak of the corresponding solution to the peak height obtained in the recovery of 0.2 µg of sulfate sulfur. If polarogram solution of the control experiment did not observe the peak of sulfur, and there is a point of inflection on the curve from the polarographic peak potential of sulfur, the wave height and take half the difference of the ordinates of inflection points and minima on the positive branch of the peak.
The installation think is workable, if the amendment reference experiment does not exceed 0,02 g of sulfur.
Amendment in the reference experiment checked before starting the analysis, the replacement of the container with argon or nitrogen solutions in barbarah and after each transition from the distillation of large quantities of sulfur to the Stripping of small amounts of sulfur.
4.3. One or two times during the working day the installation will graduate. For the calibration setup hold recovery and Stripping of sulfur of 0.2, of 0.5, 1.0, 2.0 and 3.0 cmof a solution of potassium sulfate as specified in claim 1.1.
4.2, 4.3. (Added, Rev. N 1).
5. ANALYSIS
5.1. When the mass fraction of sulfur from 5·10to 3·10
% a portion of the tellurium mass of 0.2000 g placed in a conical flask with a capacity of 50 cm
and pour 3−4 cm
mixture of nitric and hydrochloric acids (3:1). Close flask with watch glass and hold the dissolution of initially cold, and then with gentle heat not higher than 100 °C. Remove the watch glass and the solution was evaporated to dryness. The evaporation is repeated twice, each time adding 1 cm
of hydrochloric acid. Pour 3 cm
of hydrochloric acid, heated to dissolve the salts, and transfer the cooled solution into the reaction flask distilling apparatus, washing three times for 1 cm
of the wall of the flask with hydrochloric acid.
The receiver is poured 10 cmof the background electrolyte. Passed through the installation a stream of argon, through 20−30 mines after full recovery of tellurium to the elemental state bring to the boil and lead Stripping and the absorption of hydrogen sulfide for 35−40 min. the solution from the receiver is transferred to the electrolyzer and polarographic sulfide ions at a potential of minus 0.8 V (against a saturated calomel electrode).
From the height of the waves sulphur of the investigated solution is subtracted the average value of the two control experiments carried out in similar conditions; thus the average value of the wave heights of sulfur in control experiments should not exceed 30% of the wave height of the sulfur of the investigated solution.
One recovery you dare (150 cm), it is possible to consistently pursue the determination of sulfur in three batches of tellurium.
(Changed edition, Rev. N
1).
5.2. When the mass fraction of sulfur from 2·10to 5·10
% suspension of tellurium ground 1,0000 g is placed in a quartz Cup and pour the 2 cm
distilled hydrochloric acid. In the reaction vessel at the bottom pour 3 cm
of bromine, insert the Cup with the sample, close the vessel and leave for the cold at night. The next day, put the Cup in a water bath (sample must completely dissolve) and distilled off the excess of bromine. The solution was cooled and transferred into the reaction flask of the distillation apparatus with a reducing mixture of B, carrying a Cup of 2 cm
of hydrochloric acid. Further analysis is carried out as specified in clause 5.1.
(Added, Rev. N 1).
6. PROCESSING OF THE RESULTS
6.1. Mass fraction of sulfur () in percent is calculated by the formula
where is the mass of sulfur in the working solution, introduced for the calibration of the installation, mcg;
— the height of the peak polarographic solution of the sample, mm;
— arithmetic average peak height reference experiment, mm.
— the arithmetical mean height of the peak obtained during the calibration of an instrument, mm;
— weight of tellurium,
The height of the peaks used to calculate the results of the determination, count on the same instrumental sensitivity.
6.2. The difference between the two results of parallel measurements and the difference of two analysis results with a confidence probability of 0.95 should not exceed the values permitted discrepancies listed in the table.
| Mass fraction of sulfur, % | The permissible difference for parallel definitions % |
The permissible discrepancy between the results of the analysis % |
| From 0,000020 to 0,000050 incl. |
0,000007 | 0,000010 |
| SV. 0,00005 «0,00010 « | 0,00002 |
0,00003 |
| «0,00010» 0,00050 « | 0,00003 |
0,00004 |
| «0,00050» 0,00100 « | 0,00015 |
0,00020 |
| «0,0010» 0,0030 « | 0,0003 |
0,0004 |
| «0,0030» 0,0100 « | 0,0010 |
0,0015 |
| «0,010» 0,030 « | 0,003 |
0,004 |
6.1, 6.2. (Changed edition, Rev. N 1).
