Spectrophotometric system for simultaneous flow-through measurements of dissolved inorganic carbon, pH and CO2 fugacity

A flow-through CO2 measurement device, comprising:

• a first optical cell having a sample inlet and reagent inlet;
• a second optical cell having a sample inlet and reagent inlet;
• a third optical cell having a sample inlet and reagent inlet;
• an acid reservoir, a pH dye reservoir, an fCO2 dye reservoir, a DIC dye reservoir, an fCO2 reference solution reservoir, a DIC reference solution reservoir;
• a water sample source;
• a water-sample pump in fluid communication between the water source and respective sample inlets of the first, second and third optical cells;
• a second pump in fluid communication between the acid reservoir and the sample inlet of the second optical cell;
• a third pump in fluid communication between the pH dye reservoir and the sample inlet of the third optical cell;
• a fourth pump in fluid communication between the fCO2 dye reservoir and the reagent inlet of the first optical cell and in fluid communication between the DIC dye reservoir and the reagent inlet of the second optical cell;
• and
• a fifth pump in fluid communication between the fCO2 reference solution reservoir and the reagent inlet of the first optical cell and in fluid communication between the DIC reference solution reservoir and the reagent inlet of the second optical cell.