| 摘要 |
989,561. Determining oxygen absorption by absorbents. J. M. VOITH G.m.b.H. Feb. 5, 1962 [Feb. 22, 1961], No. 4264/62. Heading B1X. The oxygen consumption by an oxygen absorbent is measured by introducing a sample of the absorbent into an oxygen-containing system closed to the atmosphere, measuring the drop in. pressure in the system to obtain a measure of the oxygen consumption by the sample, and using the indication in pressure drop to replenish the oxygen content to neutralize the pressure drop, thus making the system ready for the sample to absorb more oxygen. The indication of the pressure drop may be used to supply oxygen to the closed system from an oxygen reservoir or to initiate electrolysis of copper sulphate solution using a constant electric current actuated by the level of a column of mercury which makes or breaks the electric circuit, the level of mercury being determined by the pressure in the system. The time intervals between breaking and making the circuit may be transmitted to a digital pulse counter or to a line recorder for graphical recording. The method may be carried out at constant temperature. In Fig. 3 a test vessel 1 is associated with an electrolytic cell 49 and a contact pressure gauge 48. Test substance 11 absorbs oxygen and mercury electrode 56 contacts electrodes 57 thus causing the electrolytic cell to produce oxygen which is supplied to test vessel 1 thus increasing the pressure and lowering the mercury electrode 56. A carbon dioxide absorber 8 and stirrer 9 may be provided. Recordings are obtained on the indicating device 72. Fig. 2 (not shown) shows an alternative form of test vessel wherein a hollow stopper contains carbon dioxide absorbent. The method may be used to determine the biological oxygen requirement in water supplies. |
