Hydrogen cyanide |
NO.12M |
| HCN |  |
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Performance
| Measuring Range |
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| Number of Pump Strokes |
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| Correction Factor |
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| Sampling Time | 1 minute per pump stroke | |||
| Detecting Limit | 1 ppm (n=2) | |||
| Colour Change | Yellow → Red | |||
| Reaction Principle | 2HCN + HgCl2 → Hg(CN)2 + 2HCl HCl + Base → Chloride |
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| Coefficient of Variation | 10% (for 50 to 200 ppm), 5% (for 200 to 800 ppm) | |||
| Shelf Life | 3 Years | |||
| Corrections for temperature & humidity | Unnecessary | |||
| Store the tubes at cool and dark place. | ||||
Possible coexisting substances and their interferences (NOTE)
| Substance | Concentration | Interference | Change colour by itself to |
| Hydrogen sulphide | 500 ppm | + | Red |
| sulphur dioxide | 500 ppm | + | Red |
| Calibration gas generation | Permeation tube method |
| TLV-TWA | TLV-STEL | Explosive range |
| - | C 4.7 ppm | 5.6 to 40% |
