Requirements

Before you start the synthesis, consider buying Ammonium Aluminium Disulfate Dodecahydrate directly. It is a common substance usually sold as "Ammonium alum" or "Ammonium Aluminium Alum". But if you cannot buy the substance directly, you can synthesize it yourself using other materials:

• Distilled Water
• Sulfuric Acid 44%
• Hydrochloric Acid 14% (or Sodium Chloride)
• Ammonium Nitrate
• Aluminium
• Open space or laboratory with a fume hood
• Protective gear (neoprene rubber gloves, protective goggles, lab coat)
• Fishing Line

Synthesis and Crystal Growth Procedure

Begin by wearing protective gear (neoprene rubber gloves, protective goggles, lab coat). If possible, wear a respirator as well. Make sure that you have a working fume hood or access to an open space outside a building where you can safely conduct the experiment.

Then take a large heat-resistant plastic or glass container and place it in a ventilated area. Take 30 grams of Ammonium Nitrate (~6 teaspoons) and 20 grams of Aluminium (if you take more, it is ok. It is preferable to use balled aluminium foil) and put them into your container. Pour 150 ml of hot water on top. Then slowly add 150 ml of 44% Sulfuric Acid. After that, add 25 ml of 14% Hydrochloric Acid (or 1 teaspoon of Sodium Chloride). The reaction will start to take place. Do not breathe in the gases that are produced — they are toxic. IF TOXIC GAS RELEASE HAPPENS (YOU WILL NOTICE COLORED ORANGE SMOKE OR A PUNGENT ODOR) — HOLD YOUR BREATH AND LEAVE THE AREA IMMEDIATELY. DO NOT RETURN TO THE AREA IF GAS IS VISIBLE OR CAN BE SMELLED. Leave the area for about an hour. Then regularly check if the reaction is finished (no more gas is produced).

For reference, some of the reactions involved are as follows:

After that, add 150 ml of hot water to the solution and filter it to remove undissolved impurities. Then let the solution sit in the ventilated area for an additional 24 hours so that dissolved toxic gases can escape. After that, place the solution in a cold place, if possible (DO NOT USE YOUR FRIDGE OR ANY OTHER PLACES THAT CAN BE CONTAMINATED BY TOXIC GASES). If you place your solution in a cold place, wait an additional 24 hours for everything to crystallize, then collect the product — that is your Ammonium Aluminium Disulfate Dodecahydrate. You can then prepare a solution of it to grow crystals (dissolve the product in hot water and let it cool).

Insert a fishing line into the solution and leave the system undisturbed until seed crystals begin to form. Once the crystals reach a suitable size, carefully remove excess crystals so that only one or two remain attached to each line. Transfer the saturated solution into a clean vessel, collect any residual precipitate (which may be redissolved to produce additional solution), and place the fishing line with the selected crystals into the fresh solution to continue growth. Inspect the crystals periodically and remove any new growth that forms on the line to prevent unwanted fusion with the main crystal.

After approximately 3 weeks, large, stable crystals will form. Carefully detach the crystal from the fishing line. Ammonium Aluminium Disulfate Dodecahydrate is stable under normal atmospheric conditions; therefore, no protective coating (such as nail polish) is required.

If mold happens to develop in the solution (which may occur), filter it and add a few drops of a strong mineral acid (such as Sulfuric Acid or Hydrochloric Acid) to suppress further mold growth.