Limnological Organic Analyses by Quantitative Dichromate Oxidation

Book excerpt: A limnological oxidation technique, based on procedures employed in soil chemistry, was developed and tested by use of purified organic compounds and various natural substrates. A sample is oxidized by dichromate in a strongly acid medium maintained at 100 C. The amount of dichromate reacting (determined titrimetrically as the difference between the initial and final quantities) is reckoned as Oxygen Consumed, or weigh of oxygen required by the sample. The oxidation serves as the principal step for sensitive determinations of organic carbon (as CO2) and nitrogen (as NH3).