The striking pad on books of matches is about 50% red phosphorus. The determined experimenter could obtain a pile of red phosphorus by scraping off the striking pads of matchbooks with a sharp knife. A typical composition of the striking pad is about 50% red phosphorus, along with about 30% antimony sulfide, and lesser amounts of glue, iron oxide, MnO2, and glass powder. I don't think these contaminants will seriously interfere with the reaction. Naturally, it is a tedious process to get large amounts of red phosphorus by scraping the striking pads off matchbooks, but who cares?
Making Hydroiodic Acid:
This is made by mixing iodine and red phosphorus. When making hydroiodic acid from iodine and red phosphorus, the acid is prepared first, and allowed to come to complete reaction for 20 minutes before adding the ephedrine to it. The way around the roadblock here is to just boil off some more of the water from the ephedrine extract, and make the acid mixture in fresh pure water. Since the production of HI from iodine and red phosphorus gives off a good deal of heat, it is wise to chill the mixture in ice, and slowly add the iodine crystals to the red phosphorus-water mixture.
Now, Making Methamphetamine:
To do the reaction, a 1000 ml round bottom flask is filled with 150 grams of ephedrine. Also added to the flask are 40 grams of red phosphorus and 340 ml of 47% hydroiodic acid. This same acid and red phosphorus mixture can be prepared from adding 150 grams of iodine crystals to 150 grams of red phosphorus in 300 ml of water. This should produce the strong hydroiodic acid solution needed. Exactly how strong the acid needs to be, I can't say . With the ingredients mixed together in the flask, a condenser is attached to the flask, and the mixture is boiled for one day. This length of time is needed for best yields and highest octane numbers on the product. While it is cooking, the mixture is quite red and messy looking from the red phosphorus floating around in it.When one day of boiling under reflux is up, the flask is allowed to cool, then it is diluted with an equal volume of water. Next, the red phosphorus is filtered out. A series of doubled up coffee filters will work to get out all the red phosphorus, but real filter paper is better. The filtered solution should look a golden color. A red color may indicate that all the red phosphorus is not yet out. If so, it is filtered again. The filtered-out phosphorus can be saved for use in the next batch. If filtering does not remove the red color, there may be iodine floating around the solution. It can be removed by adding a few dashes of sodium bisulfate or sodium thiosulfate.The next step in processing the batch is to neutralize the acid. A strong lye solution is mixed up and added to the batch while shaking until the batch is strongly basic. This brings the meth out as liquid free base floating on top of the water. The strongly basic solution is shaken vigorously to ensure that all the meth has been converted to the free base. You now can sell or use the free base for injection use or with free base meth now obtained, the next step you can do is to form the crystalline hydrochloride salt of meth. To do this, a few hundred mls of toluene is added to the batch, and the meth free base extracted out as usual. If the chemist's cooking has been careful, the color of the toluene extract will be clear to pale yellow. If this is the case, the product is sufficiently pure to make nice white crystals just by bubbling dry HCl gas through the toluene extract. If the toluene extract is darker colored, a distillation is called for to get pure meth free base. The yield of pure methamphetamine hydrochloride should be from 100 to 110 grams.