The Kjeldahl Nitrogen Analyzer is an instrument for quantitatively analysing elemental nitrogen by means of the Kjeldahl method.
Kjeldah method：
In the Kjeldahl method of nitrogen determination, under the condition of catalyst, the organic nitrogen is digested with concentrated sulfuric acid to convert the organic nitrogen into inorganic ammonium salt, and then the ammonium salt is converted into ammonia under alkaline condition, which is distilled with steam and absorbed by excess boric acid solution, and then titrated with standard hydrochloric acid, the amount of nitrogen in the sample can be calculated.
When using this method to determine the sample, it is generally necessary to go through four parts: digestion, distillation, absorption and titration.
1.Digestion：The sample is heated and digested with concentrated sulfuric acid and a catalyst to decompose the organic matter, in which carbon and hydrogen are oxidized to carbon dioxide and water, sulfur is released in the form of sulfur dioxide, and the organic nitrogen in the sample is converted into ammonia and combined with sulfuric acid to form ammonium sulfate.
2.Distillation: Distill the digested sample with excess alkali to distill the ammonia. During the distillation process, due to the addition of excess alkali solution, the ammonium root is extremely unstable under strong alkali conditions. Under heating conditions, the ammonium root is converted into ammonia gas and is distilled out.
3.Absorption: The distilled ammonia gas, under condensation conditions, combines with water to become ammonia water, which flows into the boric acid absorption liquid to form stable ammonium borate.
4.Titration: The distilled ammonia gas, under condensation conditions, combines with water to become ammonia water, which flows into the boric acid absorption liquid to form stable ammonium borate.
Our kjeldahl nitrogen analyzer mainly replaces the second and third processes. We have auto distillation unit, auto distillation with titration unit and full automatic kjeldahl system with autosampler.
Suitable for customers who want to upgrade the exsisting systems like glassware and manual kjeldahl device.
Our kjeldahl nitrogen analyzer can be used in argriculture, environment, food, feed, tobacco, education, pharmaceutical, science & research.
Operation process
1.Distillation part (usually automatic liquid filling)
2.Lye (40%NaOH solution): add to the digestive tract to provide alkaline environment.
3.Boric acid (2%H3BO3 solution): add the receiving cup to receive the NH3 distillate.
4.Pure water: dilute digestive juice, provide pure water for steam generator, clean equipment.
Structure demonstration of Kjeldahl nitrogen analyzer
1. A number of safety tests monitor the instruments at the same time to ensure the safety of personnel and instruments in the testing process.
2. Selection of anti-splash bottle material: the service life of imported plastic material is 200% longer than that of traditional glass material.
3. In the "titration while distillation" mode, titration is carried out while the sample is distilled, which can shorten the test operation time by more than 40%.
4. The linear motor directly promotes the piston pump technology, and the minimum titration volume is increased from the original 2.4uL/ step to the 1uL/ step.
5. The steam generator adopts aluminum heating cup and multiple protection devices to ensure the rapid heating of the test and protect the safety of the instrument.
6. The original metal condensation method is adopted. as for the outlet of the condensate of the condensate bottle, the temperature sensor ensures that the temperature of the effluent does not exceed the temperature and ensures the accuracy of the test results.
