GOST 23859.4-79
GOST 23859.4−79 heat-resistant Bronze. Method for the determination of phosphorus (with Amendments No. 1, 2)
GOST 23859.4−79
Group B59
INTERSTATE STANDARD
BRONZE HIGH-TEMPERATURE
Method of determination of phosphorus
Bronze fire-resistance. Method for the determination of phosphorus
AXTU 1709
Date of introduction 1981−01−01
Resolution of the USSR State Committee for standards, dated 16 October 1979, N 3937 time of the introduction set with 01.01.81
Limitation of actions taken by Protocol No. 5−94 of the Interstate Council for standardization, Metrology and certification (ICS 11−12−94)
EDITION with Amendments No. 1, 2 approved in June 1985, March 1990 (IUS 9−85, 7−90).
This standard sets the photometric method for the determination of phosphorus at a mass fraction of from 0.005 to 0.02% copper high-temperature alloys.
The method is based on formation of yellow phosphorus-vanadium-molybdenum complex and the measurement of its optical density.
(Changed edition, Rev. N 1, 2).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 25086−87 with the addition of a GOST 23859.1−79, sec. 1.
(Changed edition, Rev. N 2).
2. APPARATUS, REAGENTS AND SOLUTIONS
Photoelectrocolorimeter or spectrophotometer.
Hydrochloric acid by the GOST 3118−77.
Nitric acid GOST 4461−77 and diluted 1:1, 1:3, 1:2.
A mixture of acids consisting of 400 cm
of concentrated hydrochloric acid, 100 CCof concentrated nitric acid and 500 cmof water.
Sulfuric acid GOST 4204−77, diluted 1:1.
Ammonia water according to GOST 3760−79.
Ammonium neccersarily according to GOST 20478−75, a solution of 100 g/DM.
Rectified ethyl alcohol GOST 18300−87 and diluted 5:8.
Ammonium undeviatingly meta GOST 9336−75, a solution of 2.5 g/DM: 2.5 g of the drug dissolved in 500−700 cmof hot water in a volumetric flask with a capacity of 1 DM, cooled to room temperature, add 20 cmof concentrated nitric acid, made up to the mark with water and mix.
Ammonium molybdate according to GOST 3765−78, recrystallized from alcoholic solution, a freshly prepared solution 50 g/DM.
For recrystallization 250 g ammonium molybdate, h. d. a. dissolved in 400 cmof water when heated to 70−80 °C, ammonia is added to a clear smell and the hot solution is filtered twice through the same dense filter into a glass contains 300 cmof ethyl alcohol. The solution was cooled to 10 °C and allowed to stand for 1 h. the Precipitated crystals are filtered off through a Buchner funnel, sucking mother liquor. The crystals are washed 2−3 times with ethanol, portions at 20−30 cmafter which they are dried in air.
Ammonium nitrate according to GOST 22867−77, a solution of 20 g/DM.
Iron, the reduced hydrogen.
Iron nitrate, solution 1 g/DM, is prepared as follows: 0.5 g of iron, reduced hydrogen, dissolved in 20 cmof nitric acid, diluted 1:3 and diluted with water to 500 cm.
Alum salesonline on the other 6−09−5359−87, a solution of 100 g/DM10 g of alum was dissolved with heating in 70 cmof water with the addition of 5 DMof concentrated nitric acid, the solution filtered and diluted with water to 100 cm.
Sodium phosphate disodium GOST 4172−76.
Potassium phosphate according to GOST odnosemjannyj 4198−75.
The standard solutions of phosphorus.
Solution A. 0,4395 g of single phosphate or potassium 0,4586 g twosemester sodium phosphate (previously dried at 105 °C to constant weight) was placed in a volumetric flask with a capacity of 1 DM, is dissolved in water, made up to the mark with water and mix. 1 cmof the solution contains 0.0001 g of phosphorus.
Solution B. 20 cmof solution A is placed in a volumetric flask with a capacity of 100 cmand then filled to the mark with water. 1 cmof solution B contains 0,00002 g of phosphorus.
Sec. 2. (Changed edition, Rev. N 1, 2).
3. ANALYSIS
3.1. A sample weighing 1 g is placed in a beaker with a capacity of 400 cm, add 10 cmof a solution of nitrate of iron, or 1 cmof a solution of alum salesonline, 30 cmof the mixture of acids to dissolve, cover with a watch glass and dissolved under heating. After cooling, add 30 cmof sulphuric acid diluted 1:1, and is evaporated prior to the allocation of white smoke of sulfuric acid. The residue is cooled, rinse walls of beaker with water and again evaporated prior to the allocation of white smoke of sulfuric acid. Again cool, add 250 cmof water and heated to dissolve the residue. To the hot solution add 10 cmof naternicola solution of ammonia, heated to boiling, and boil to decompose the excess ammonium naternicola. Cooled to 60−70 °C, rinse walls of beaker with water, add 10 cmof nitric acid, diluted 1:1, and precipitated ferric hydroxide with ammonia, carefully adding it to the formation of the soluble ammonia complex of copper and beyond that another adds 5−6 cmof ammonia. The mixture was incubated for 1 h at 60−70 °C for coagulation of the precipitate of iron hydroxide. The precipitate was filtered off on a filter of medium density. The sediment and the walls of the beaker are washed free of copper and chromium 7−8 times with hot ammonium nitrate solution with the addition of 2 cmof ammonia solution per 1000 cm, then 1−2 times with hot water, the precipitate is dissolved in 18 cmof nitric acid (1:2), washed 3−4 times with hot water, collecting the solution in the beaker. The solution is evaporated to a volume of 15−20 cm. Rinse walls of beaker with water, the solution was cooled, poured 10 cmof the solution vadeevaloo ammonium and 10 cmof a solution of molybdate of ammonium. After each addition of the reagent the solution was stirred. The mixture was transferred to a volumetric flask with a capacity of 50 cm, made up to the mark with water and measure the optical density in a cuvette with a thickness of the absorbing layer of 5 cm at a photoelectrocolorimeter with a blue filter or in a cuvette of 1 cm on the spectrophotometer at 400 nm. As a solution comparison, using a solution blank sample processed through the entire analysis with the addition of vadeevaloo and molibdenovykh
about ammonium.
3.2. Construction of calibration curve
In glasses with a capacity of up to 100 cmflow consistently 0; 1,0; 2,0; 3,0; 4,0; 5,0; 6,0; 8,0 and 10.0 cmstandard solution B phosphorus, poured 18 cmof nitric acid (1:1) and then received, as indicated in paragraph 3.1. As a solution comparison, using a solution containing no phosphorus.
Sec. 3. (Changed edition, Rev. N 1, 2).
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of phosphorus (
) in percent is calculated by the formula
,
where 
is the mass of phosphorus was found in the calibration schedule g;
the weight of bronze,
4.2. Discrepancies in the results of three parallel definitions should not exceed the values permitted by the divergence 
(the rate of convergence), calculated according to the formula
,
where — mass fraction of phosphorus in the alloy, %.
(Changed edition, Rev. N 2).
4.3. Discrepancies in the results analysis, obtained in two different laboratories or two of the results of analysis obtained in the same laboratory but under different conditions (
a measure of reproducibility) shall not exceed the values calculated according to the formula
,
where — mass fraction of phosphorus in the alloy, %.
4.4. Control of accuracy of analysis results is carried out according to State standard samples of heat-resistant (CR) bronze or by a method of additives in accordance with GOST 25086−87.
4.3, 4.4. (Added, Rev. N 2).
