The Kjeldahl nitrogen analyzer is a professional instrument used to determine the protein content and nitrogen content of samples. It has a wide range of applications in grain and oil detection and many other fields. The automatic Kjeldahl nitrogen analyzer has a high degree of automation and good safety. It is a favorite of users. The new Kjeldahl nitrogen analyzer product, this article mainly introduces the determination steps of the automatic Kjeldahl nitrogen analyzer, that is, the step method of the automatic Kjeldahl nitrogen analyzer to determine protein. Since there are many models of automatic Kjeldahl nitrogen analyzer, and different models of products, the determination steps are different, so this article mainly introduces the ZDDN-II automatic Kjeldahl nitrogen analyzer in detail. 1. Reagent preparation 1. Digestive tube reagent preparation: 2. Preparation of lye reagent: 3. Preparation of lye reagent: 4. Preparation of mixed indicator: 2. Operation steps 1. Digestion steps: 2. Distillation steps: 3. Titration: 4. Calculation: Reminder: Since the automatic Kjeldahl nitrogen analyzer will continue to optimize and improve its technology with the development of science and technology and experimental needs, the determination steps of the automatic Kjeldahl nitrogen analyzer will also change with the model upgrade. The above operation steps may It is no longer suitable for upgrading product operations, so to obtain the latest automatic Kjeldahl nitrogen determination procedure, please check the product manual, or contact the manufacturer’s technicians. Polyethylene Glycol,Polyethylene Glygcol,Poly Ethylene Glycol,Polyethylene Glycol Series Jiangsu Zhongluman New Material Technology Co., Ltd , https://www.zjrozhmch.com
Step 1: First use an electronic balance to weigh a solid sample (soy flour) between 0.2g-2g and record it as m, and pour it into the digestive tube;
Step 2: Add copper sulfate. First use an electronic balance to weigh 0.2g of copper sulfate, and pour it into the digestive tube in the same way;
Step 3: Add potassium sulfate, first weigh 6g potassium sulfate with an electronic balance, and pour it into the digestive tube the same way;
Step four, add concentrated sulfuric acid. Finally, add 20ml of concentrated sulfuric acid with a pipette.
First, weigh 400g of sodium hydroxide, pour it into the prepared beaker, then add 1000ml of distilled water, stir well, and pour it into a plastic bottle.
First, weigh 400g of sodium hydroxide, pour it into the prepared beaker, then add 1000ml of distilled water, stir well, and pour it into a plastic bottle.
First use an electronic balance to weigh out 0.1g of methyl red and pour it into beaker 1, then use an electronic balance to weigh out 0.5g of bromocresol green and pour it into beaker 2, measure 100ml of ethanol and pour it into beaker 1. Pour the same amount of 100ml of ethanol into beaker 2. After stirring evenly, pour the solutions in beaker 1 and beaker 2 into the large beaker. After stirring, pour the reagent in the large beaker into the reagent bottle.
Step 1: First, put the prepared reagent into the digestion furnace for digestion, connect the collection tube to the digestion tube, clamp the middle with a fluorine rubber ring to prevent gas leakage, and then connect the suction pump to discharge the exhaust gas and tap water into the sewer together .
Step 2: Connect the power cord, turn on the switch, turn on the instrument, press the [Set] key to enter the main page, and start to set the temperature to be heated, etc. After the setting is completed, select [Start] and click OK to start digestion. After the digestion is completed, the test tube will be included. The rack is moved to the test tube mounting base for cooling,
Step 3: Install the Erlenmeyer flask on the base of the Erlenmeyer flask, move the tray left and right to move the Erlenmeyer flask up and down, and then install the digestion tube on the base of the digestion tube.
Connect the power cord, turn on the switch, and turn on the instrument. After the language selection is completed, the system will automatically add water, and the instrument can automatically set various parameters. In manual mode, directly press the [acid addition], [alkali addition], or [distillation] keys to complete acid addition, alkali addition, and distillation After the operation is completed, remove the conical flask.
Hydrochloric acid preparation: first adjust the pipette to 0.417ml, add to the volumetric flask after aspiration, add an appropriate amount of distilled water to make the volume 100ml, and then pour the prepared 0.05mol/L hydrochloric acid solution into the acid burette to the 0 mark , And finally add 2-3 drops of mixed indicator for titration. Titrate until the gray matter, and write down the number of milliliters consumed by HCL, which is V1.
According to the calculation formula, calculate the final result.
March 01, 2024