Procedure for Distilling Samples on the Kjeltec 2300 Analyzer Unit
- Turn power on.
- Turn printer on.
- Turn water on.
- Go to manual mode.
- Flick titrating tube to get bubbles out. Dispense titrant several times to get bubbles out.
- Go to steam on. Press arrow key to turn steam on. Allow to warm up for 5 minutes.
- Press arrow key to turn steam off.
- Go to analysis mode.
- Select program.
- Go to result. Select blank.
- Have tube containing water in place.
- Close door.
- Run at least two blanks. Make sure the blank value is around 0.10 or less.
- Go to result and change to % Nitrogen. (The blank number above should read the last blank value you ran.)
- Put a tube with 1 mL of the 1% N solution standard and some water in place. Input 1.0 for the weight.
- Close door and let run. Readout should be close to 1% (+ 0.05%).
- Proceed with samples. Run the glycine check first. Input the correct weight for each sample. (The result for the glycine check should be close to 18.66 % N.)
- If you have blanks within the set run a tube with just water first to flush out the system, then run the blank. (Change result to blank for running the blank then back to % N for the samples. Input the weight for the samples as above.)
- Record numbers from printout into nitrogen book and onto lab sheets with 2 decimals.
- %N = 14.01 x N H2SO4 x (mL acid)/(sample wt(g) x 10)
- % Crude Protein = %N X 6.25
Shut Down and Maintenance
- Place tube with water in unit. Select manual. Go to steam on. Press arrow key and allow generator to run for about 5 minutes. Press arrow key to turn steam off. Remove tube and dispose of contents.
- Turn power off.
- Turn water off.
- Turn printer off.
- Clean drip tray. Clean the shield. Rinse and inspect the rubber adapter. Wipe any spillage with a damp cloth. Squirt water into titration vessel and onto pins to clean.
- Place empty tube in unit and close shield.
- Check and clean around reagent tank screw caps to remove crystals. Every one to three months:
- Clean alkali pump. Put 2 L of warm distilled water in a beaker. Put alkali tube into beaker. Select manual mode. Select add alkali several times. Empty distillation tube as needed. (A rinse using a half a liter of warm water is sufficient.) Replace hose into alkali tank. Flush out residual water and remove entrapped air.
- Clean receiver solution dispensing system as above only if contamination has occurred.
- Check volume of alkali. Go to manual mode. Select the pump you want. Measure dispensed liquid. Adjust as necessary.
- Check volume of receiver solution. Put drain tube into measuring cylinder. Go to manual mode. Select add receiver. Adjust as necessary.
- Clean splash head. Put 25 mL distilled water and 25 mL acetic acid into distillation tube. Select manual. Go to steam on for 5 to 10 minutes. Turn off steam. Replace tube with tube containing 50 mL distilled water. Distill for 5 minutes. Repeat the distillation three times with fresh water.
- Inspect all tubing and connectors.
- Brenner, J. M. 1965. Total Nitrogen. In C. A. Black (ed) Methods of Soil Analysis, Part II, SSSA., Madison, Wis. p.1149-1178.
- Horwitz, W. (ed). 1970. Official Methods of Analysis of the AOAC, 11th Edition, Washington, D. C. p.16-17.
- Tecator Manual. Kjeltec System 2300 Distilling Unit. Tecator, Hoganas, Sweden.