| 摘要 |
952,155. Gas analysis systems. W. SIMON. Oct. 24,1962 [Nov. 9, 1961], No. 40291/62. Heading G1B. A method of quantitatively analysing gaseous mixtures, which contain a specific amount of a rapidly and quantitatively removable component, comprises passing the mixture through a first thermal conductivity analyser e.g. a Katharometer 7, then through a device e.g. an absorption tube 9, which quantitatively removes the component, and subsequently through a second thermal conductivity analyser, e.g. a Katharometer 8, adjusting the flow by means of a cock 3 till it reaches a steady state, and comparing the output signals of the two Katharometers in a measuring instrument 10, which gives a differential signal proportional to the specific amount. The apparatus shown may be used for performing analysis of a single component in a gas mixture e.g. determination of oxygen in organic compounds by distillation of the compound in helium e.g. at 900‹C., conversion of the cleared oxygen to carbon monoxide by passage over carbon in the tube 9 at 1100‹C., and subsequent quantitative analysis of the carbon monoxide. A reservoir 6 and a pressure-balancing vessel 5 are provided, cocks 1, 4 controlling the entry and exit of gas to the apparatus. In use, the apparatus, except the reservoir 6, is evacuated and the gas mixture is allowed to flow from the reservoir by opening the cock 3. At the steady state the differential signal of the two Katharometers 7, 8 is measured, and the proportion of carbon monoxide computed. This apparatus may also be used in the analysis of carbon dioxide in the atmosphere, components of flue gases, or combustion products of organic compounds. For simultaneous analysis of several components of a gas mixture, a number of the arrangements shown of the tube 9 and Katharometers 7, 8 are connected in' series (Fig. 2, not shown), the Katharometers being held by thermostats at a constant 25‹C. Such an apparatus may be used for a carbon, nitrogen, hydrogen determination of an organic compound, which is heated in a stream of helium with potassium chlorate in a combustion tube, the produced gases being analysed after removal of excess oxygen by passage over copper. The hydrogen content is determined by removal of the water produced using phosphorus pentoxide in the first absorption tube, the carbon dioxide is removed using sodium asbestos in the second tube, and the nitrogen is subsequently removed by reaction with magnesium at 600‹C. |
