Determination of proportion of gaseous component in mixture of gases e.g. CO

摘要

The method is colorimetric in which a constant flow of the sampled gas is produced in a glass capillary tube (3) filled with a fine granular indicator (4). The colour of the indicator within a defined volume is visible through a window (6) in the jacket (5) surrounding the tube, at which radiation is directed from a source (7). A remission signal I(t) is detected (8) and its rate of increase is worked out over an interval during which an excess of indicator remains. After the chemical reaction a saturation remission signal is determined corresponding to almost complete conversion.