Skip to product information
1 of 4

PayPal, credit cards. Download editable-PDF & invoice in 1 second!

YS/T 575.21-2007 English PDF (YST575.21-2007)

YS/T 575.21-2007 English PDF (YST575.21-2007)

Regular price $160.00 USD
Regular price Sale price $160.00 USD
Sale Sold out
Shipping calculated at checkout.
Quotation: 24-hr self-service. Click YS/T 575.21-2007
See Chinese contents: YS/T 575.21-2007

YS/T 575.21-2007: Methods for chemical analysis of bauxite. Part 21: Determination of organic carbon content. Titrimetric method

This Part specifies the determination method of organic carbon content in bauxite. This Part applies to the determination of organic carbon content in bauxite. Determination range: 0.01% ~ 1.00%.
YS/T 575.21-2007
YS
NONFERROUS METALS INDUSTRY STANDARD
OF THE PEOPLE REPUBLIC OF CHINA
ICS 71.100.10
Q 52
Replacing YS/T 575.21-2006
Methods for Chemical Analysis of Bauxite - Part 21:
Determination of Organic Carbon Content - Titrimetric
Method
ISSUED ON: NOVEMBER 14, 2007
IMPLEMENTED ON: MAY 01, 2008
Issued by: National Development and Reform Commission
Table of Contents
Foreword ... 3
1 Scope ... 6
2 Method Principle ... 6
3 Reagents ... 6
4 Determination Device ... 7
5 Specimen ... 8
6 Analysis Procedures ... 8
7 Calculation of Analysis Results ... 9
8 Precision ... 10
9 Quality Assurance and Control ... 10
Methods for Chemical Analysis of Bauxite - Part 21:
Determination of Organic Carbon Content - Titrimetric
Method
1 Scope
This Part specifies the determination method of organic carbon content in bauxite. This Part applies to the determination of organic carbon content in bauxite. Determination range: 0.01% ~ 1.00%.
2 Method Principle
After boiling and decomposing carbonate by phosphoric acid, use silver sulfate as a catalyst. Use potassium persulfate to oxidize the carbon in the organic matter to carbon dioxide; and then use thymolphthalein as an indicator; then use ethanol-ethanolamine- potassium hydroxide solution to absorb and titrate.
3 Reagents
3.1 Silver sulfate.
3.2 Phosphoric acid (1+1).
3.3 Saturated aqueous solution of potassium persulfate.
3.4 Sodium oxalate standard solution: take 0.2000g of sodium oxalate (reference substance) that has been dried at 130??C in advance; dissolve it by water; transfer it to a 200mL volumetric flask; dilute to the mark with water; and shake it well. 1mL of this solution contains 1mg of sodium oxalate.
3.5 Ethanol-ethanolamine absorption solution: mix evenly 900mL of absolute ethanol with 100 mL of ethanolamine; and add 0.1g of thymolphthalein to mix evenly. 3.6 Ethanol-ethanolamine-potassium hydroxide standard titration solution: dissolve 1.3g of potassium hydroxide in 900mL of absolute ethanol; stand for one day; filter out the insoluble matter. Add 100mL of ethanolamine and 0.1g of thymolphthalein indicator; mix evenly. The concentration of the solution is determined in accordance with sub- 8 - Condensing tube;
9 - Three-necked flask, 500mL;
10 - Electric furnace;
11 - Separating funnel, 100mL;
13 - Gas scrubber, containing 20% copper sulfate;
16 - Absorption cup, containing absorption solution;
17 - Reference cup, containing absorption solution;
18 - Burette.
Figure 1 ?€? Determination Device
5 Specimen
Grind the specimen by a mortar to pass through a 71??m sieve; dry the ground specimen at 110??C??5??C for 2h; place it in a desiccator; and cool to room temperature for later use.
6 Analysis Procedures
6.1 The number of determinations
The same specimen shall be determined for twice independently and the average value shall be taken.
6.2 Blank test
Do a blank test with the testing material.
6.3 Connect the determination device according to the diagram of the determination device; add ethanol-ethanolamine absorption solution (3.5) to the absorption cup and the reference cup, respectively; so that the liquid level of the solution is 2cm~4cm above the sieve plate in the cup. Ventilate (control the flowrate to about 0.3L/min); use ethanol-ethanolamine-potassium hydroxide standard titration solution (3.6) to titrate until the solution is stable blue (the color in the absorption cup is the same as the reference cup); stop ventilation.
6.4 Remove the carbonate in the specimen and the carbon dioxide in the system

View full details