Section I Gravimetric Method
1 Subject Content and Application Scope
This standard specifies the determination of sulfur content by barium sulfate gravimetric method.
This standard is applicable to the determination of sulfur content in limestone products for chemical industry and the determination range is greater than 0.05%.
2 Normative Reference
GB 6682 Water for Analytical Laboratory Use - Specification and Test Methods
3 Method Summary
Decompose the specimen with nitric acid and potassium chlorate, oxidize sulfur to sulfate, add hydrochloric acid and evaporate to dryness, so as to remove the nitric acid. Filter the solution to remove insoluble substances like silicon; in hydrochloric acid medium with pH value of about 1, add barium chloride to generate barium sulfate precipitate. Then, filter out the barium sulfate, precipitate, ignite and weigh it, and then calculate the sulfur content by the mass of barium sulfate. •
4 Reagents and Solutions
Water used in this standard shall conform to the specification of Grade 3 water specified in GB 6682; unless otherwise specified, the adopted reagents refer to analytical reagents.
4.1 Potassium chlorate (GB 645).
4.2 Nitric acid (GB 626) solution: 1+1.
4.3 Hydrochloric acid (GB 622).
4.4 Hydrochloric acid solution: 1+1.
4.5 Hydrochloric acid solution: 1+100.
4.6 Hydroxylamine hydrochloride (GB 6685) solution: 50g/L.
1 Subject Content and Application Scope
2 Normative Reference
3 Method Summary
4 Reagents and Solutions
5 Specimen
6 Analytical Procedures
7 Expression of Analysis Results
8 Allowable Difference
9 Subject Content and Applicable Scope
10 Normative Reference
11 Method Summary
12 Reagents and Solutions
13 Apparatuses
14 Specimen
15 Analytical Procedures
16 Expression of Analysis Results
17 Allowable Difference
Additional Information
