Ammonia (dilute)
Dilute ammonia is produced by many biological processes, but can also be produced with relative ease.
Primary
- Feedstock for ammonia
Secondary
- Antibacterial and insect repellant qualities
Natural occurrence
- Ammonia is produced directly by most aquatic creatures, and excreted in their urine
- The urea in land animal urine hydrolyses naturally into dilute ammonia
Hazards
Production
Extraction
Air stripping
- Needed: One large lidded or sealable container, and a smaller open-topped container that can be placed upright within the larger one.
- Fill the larger container to a shallow depth with urine.
- Add some grass to make sure there are sufficient bacteria to start
- Repeat this process
- Place the lid on the large container
- Wait one day
- Lift the lid on the large container
- Smell the urine
- Check There should be no bugs, living or dead, in the container with the urine.
- Until the urine smells strongly of ammonia
- Fill the small container with a small amount of distilled water
- Place the smaller container upright within the larger container, not getting the water in the urine or the urine in the water
- Replace the lid on the larger container
- Wait for several (warm) days
- Remove the small container from the large container.
- The large container now contains stale urine. Discard or add to compost to promote nitrogen growth.
- The small container now contains dilute ammonia
Synthesis
Dry distillation
dry distillation of horn, hoof, and other nitrogenous organic matter produces some ammonia.
Dung burning
Basically a variation on the above process: burn the (urine soaked) dung at a low temperature and collect the ammonium chloride (NH4Cl) left in the ash. Add Sodium Hydroxide to release the ammonia.
Kjeldahl
Ammonia can be produced from the ammonium sulfate produced by the Kjeldahl method. This is wildly inefficient, but relatively simple. An arbitrary nitrogen-bearing organic compound [H•C•O•N•] is dissolved in hot sulfuric acid while providing excess oxygen. This results in carbon dioxide, water, and ammonium bisulfate. The carbon dioxide escapes, and the ammonium bisulfate solution is evaporated until crystals begin to form. Water is added to form a completely saturated solution of ammonium bisulfate, then sodium hydroxide is added, producing a sodium sulfate solution and gaseous ammonia.
- H•C•O•N• + H2SO4 → CO2 + H2O + NH4SO4
- Form saturated solution
- NH4SO4 + NaOH → NH3 + 2 H2O + Na2SO4
Purification
Concentration of dilute ammonia
Boiling ammonia water, then condensing or water-washing the vapors can get you to near 40%, which is a practical maximum at standard pressure.
See Also
Web
- "A Guide to Kjeldahl Nitrogen Determination Methods and Apparatus"
link courtesy Expotech USA. - Concentrating household ammonia