Case Study

Carbon Hydrogen Nitrogen Determination in Coal and Coke

Sample Preparation
Crush & Grind the sample to size ≤ 0.2(GB) / 0.212(ISO) / 0.25mm (ASTM). Air dried Moisture should be tested by oven or TGA in case of calculating dry basis value

5E-CHN2200 Elemental Analyzer

Instrument Settings

Oxygen Flow (SV4): 3L/min; 
Oxygen Flow (SV5): 0.8L/min; 
Oxygen Flow (SV6): 0.3L/min;
Main Furnace Temperature: 950 ℃; 
Secondly Furnace Temperature: 850 ℃ 
Nominal Sample Weight: 80 mg;
Analysis Time: 6 minutes per analysis;

Special Modifications to Unit

Method Approval
GB/T 30733 ASTM D5373 AS 1038.6.4 ISO 29541


1. Prepare instrument as outlined in the operator’s instruction manual (perform maintenance and leak checks, etc.);
2. Purging and analyze blanks until instrument is stable (nitrogen results will reach a plateau);
3. Calibrate by CRM EDTA;
4. (4-5) blanks and (1-2) waste samples to condition the instrument
5. 3 samples of calibration substance to check or carry out the calibration;
6. Run 9 sample analyses
7. 2 samples of calibration substance to check the calibration;
8. Repetition of point 5 to point 6 until all samples are processed;

Do Calibrating refer to operator’s instruction manual for details.

Typical Results

1Coal 10.080182.984.271.80
2Coal 10.081682.934.201.76
3Coke 30.079290.434.030.95
4Coke 30.081390.543.961.01