GOST 1219.6-74
GOST 1219.6−74 calcium Babbits. Method for determination of antimony
GOST 1219.6−74
Group B59
INTERSTATE STANDARD
CALCIUM BABBITS
Method for determination of antimony
Lead-calcium bearing alloys.
Method for determination of antimony content
ISS 77.160.20*
____________________
* In the index «National standards» 2006
ISS
Date of introduction 1975−01−01
The decision of the State standards Committee of the Council of Ministers of the USSR from January 17, 1974 N 150 date of introduction is established 01.01.75
Limitation of actions taken by Protocol No. 2−92 of the Interstate Council for standardization, Metrology and certification (ICS 2−93)
REPLACE GOST 1219−60 in part of sec. VII
REPRINTING. September 2003
This standard applies to calcium babbits and sets the volumetric method for determination of antimony (in mass fraction of antimony from 0.05 to 0.30%).
The method is based on the oxidation of trivalent antimony to pentavalent during the titration with a solution of potassium bromate in presence of methyl orange indicator.
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 1219.0−74.
2. REAGENTS AND SOLUTIONS
Sulfuric acid according to GOST 4204−77.
Hydrochloric acid by the GOST 3118−77.
Potassium branovitsky according to GOST 4457−74, 0.01 N. the solution is prepared as follows: 0,2784 g of potassium bromate are dissolved in water in a volumetric flask with a capacity of 1 DM, adjusted to the mark with water and mix.
Methyl orange (pair-dimethylaminoazobenzene sodium).
Antimony GOST 1089−82 brand Su00.
The installation of the titer of a solution of potassium polnovatogo
To install the titer of 3−4 flasks with a capacity of 250 cmis placed on 0,0120 g of powdered metallic antimony, poured 20 cm
of sulfuric acid and dissolved by heating. The cooled solution was poured in 100 cm
of water and 20 cm
of hydrochloric acid and boiled for 10 min, then the solution was cooled to 70−80 °C, introduce 2−3 drops of 0.1% methyl orange indicator and titrated solution of potassium polnovatogo to the disappearance of the pink color of the solution.
The titer of a solution of potassium bromoperoxidase (), expressed in g/cm
of antimony, calculated by the formula
where — hanging antimony, g;
— the amount of potassium bromate solution consumed for titration of antimony, cm
.
The final titer of the solution of potassium bromate taking the arithmetic mean of the results of 3−4 determinations.
3. ANALYSIS
A portion of the babbit 1.0 g placed in a flask with a capacity of 250 cm, add 20 cm
of sulfuric acid and heated at high temperature to dissolve the alloy. At the time of the dissolution, the flask closed with a small funnel. After decomposition of the alloy the flask is cooled, then carefully along the walls of the flask pour 100 cm
of water and 50 cm
of hydrochloric acid and boiled for 10 min. the solution was Then cooled to 70−80 °C, add 2−3 drops of 0.1% methyl orange indicator and titrated with 0,01 n solution of potassium polnovatogo to the disappearance of the pink coloration of the solution. At the end of the titration, add another drop of indicator solution.
At the same time through all stages of the analysis carried out control experience on the determination of antimony in reagents.
4. PROCESSING OF THE RESULTS OF THE ANALYSIS
4.1. Mass fraction of antimony () in percent is calculated by the formula
where is the number of potassium bromate solution consumed for titration of sample solution, cm
;
— the amount of potassium bromate solution consumed for titration of the solution in the reference experiment, cm
;
the titer of a solution of potassium Bromeliaceae, expressed in g/cm
of antimony;
— hanging Babbitt, g
.
4.2. The allowable divergence between the extreme results of the analysis shall not exceed 0.008 abs. % — mass fraction of antimony from 0.05 to 0.1% and 0.02 abs. % — mass fraction of antimony from 0.1 to 0.3%.
