AUTOMATED-DETERMINATION OF CARBON IN NATURAL-WATERS

An automated method for determining inorganic C and organic C in water is described. The sample is acidified, and the CO2 from inorganic carbonate is removed in a packed column and measured with an IR analyzer. The stripped liquid is pumped to a furnace containing cobalt oxide catalyst at 950.degree. C where the organic C is oxidized; the resulting CO2 is measured with an IR analyzer. Operating as a 2-channel system, inorganic C and organic C are measured simultaneously at 20 samples/h. If used in a single-channel mode, inorganic and organic C are measured separately, inorganic C at 60 samples/h, organic C at 20 samples/h. The coefficients of variation at 1 and 5 mg l-1 organic C are 5.1 and 2.8%, respectively. The detection limit is 200 .mu.g l-1 C.