Total Kjedahl Nitrogen (TKN)

Total Kjeldahl Nitrogen (TKN) is a parameter used to measure the total nitrogen content in a sample. It includes both organic and inorganic forms of nitrogen. TKN analysis involves a chemical digestion method known as the Kjeldahl method. In this method, the sample is digested with sulfuric acid and a catalyst, converting the organic nitrogen into ammonium sulfate. The ammonium ions are then distilled and collected in an alkaline solution. Finally, the collected ammonia is titrated with a standardized acid solution to determine the TKN concentration. TKN is an important parameter in wastewater and environmental analysis, as nitrogen compounds can contribute to water pollution and impact ecosystems. By measuring TKN, scientists and engineers can assess the nitrogen load in various samples, including wastewater, surface water, and soil. It helps in evaluating the effectiveness of nitrogen removal processes in wastewater treatment plants and monitoring the environmental impact of nitrogen-rich discharges.

He was a Danish chemist who developed a method for determining the amount of nitrogen in certain organic compounds using a laboratory technique which was named the Kjeldahl method after him.