57% Hydriodic Acid
Step by Step Write-Up

• Intro
• Background and Terms
• General Overview
• Step-by-Step Instructions
• Obtain ingredients
• Test ingredients
• Mix ingredients
• React ingredients
• Redistill product
• Hypothetical considerations
• Instructions for buying a new Cadillac
• Conclusion

This is a really long-winded write-up, but have faith; your patience will be rewarded. Mixed in with a boring discussion of chemical reactions, I've decided to liven things up by including detailed instructions on how to obtain a new luxury car, so bear with me.

Argox has been slandered on this Forum. But none dare say poseur. The following write-up is based on EXPERIENCE, not made-up bullshit that passes for knowledge.

Hydriodic acid is illegal to manufacture or possess in California. It may even be illegal where you live. Find out. In the republic where Argox resides, a person can manufacture hydriodic and not go to jail. The jail time comes from making meth with it, or selling it to meth chemists, but avoiding prison is where your native cunning comes into play. Check out the legality of hydriodic in your neck of the woods before you make several hundred liters, just in case.

Hydriodic acid is a fuming corrosive liquid, clear yellow to muddy brown in color. Hydrogen iodide is a transparent fuming corrosive gas. 57% hydriodic acid is a constant boiling (127ºC/760 mm) mixture of hydrogen iodide and water.

In this write-up, the notation HI will refer to hydrogen iodide--a gas. The notation HI_(aq) will refer to 57% hydriodic acid--a liquid.

HI_(aq) is used in the clandestine production of meth amphetamine. HI_(aq) reduces ephedrine to methamphetamine and can be regenerated by red phosphorus (RP) and water. Instructions for making meth using this method can be found elsewhere on this Forum. I don't know if the instructions are any good or not. I've never made meth and don't know fuck all about making it. This is absolutely true. However, I am familiar with its market dynamics.

HI and HI_(aq) are strictly and successfully controlled by the war-on-drugs agencies, since these compounds are relatively obscure and little used by industry. Any attempt to purchase HI or HI_(aq) from a legitimate supplier will draw the attention of the authorities. Guaranteed.

Ephedrine-based meth laboratories in the 50 to 100 kg/week range will have clandestine sources for ephedrine, RP, and HI_(aq). The black market price of HI_(aq) varies according to local market conditions. It ranges from $us[deleted] to $us[deleted]per liter in North America, with wide swings in price in the same area depending on its availability and the amount of meth manufacture taking place at the time. A liter of HI_(aq) weighs 1,700 grams and contains 970 grams of HI.

The clandestine meth chemist without a black market source for HI_(aq), or the enterprising chemist who wishes to supply the former, have three choices for making HI_(aq):

1. Combine iodine and red phosphorus, carefully add water. This method is widely used by those chemists who supply meth labs with HI_(aq). However, it has the disadvantage of using watched chemicals. Red phosphorus (RP) is controlled. Iodine (I₂) is watched. Obtaining OTC RP and I₂ is not a serious endevour. OTC RP from match box strikers and OTC iodine from tincture is time consuming and labor intensive. Only tweakers will attempt to make their own RP and I₂. Besides, this write-up is all about making HI_(aq) from innocuous non-watched ingredients at any scale.

2. Bubble hydrogen sulfide gas through an aqueous slurry of I₂, distill HI_(aq).

   H₂S + I_2(aq) --> 2HI_(aq) + Sº

   This method is suitable for large-scale production of HI_(aq). The disadvantage is that hydrogen sulfide is extremely poisonous. I really want to stress that the novice clandestine chemist should never attempt to generate H₂S. H₂S is a deadly poison. There is no antidote. With a lethal dose measured in small ppm's, death can be expected in 15 minutes from acute cellular asphyxiation.

   I was once gassed with hydrogen cyanide, which is similar in toxicity to hydrogen sulfide, luckily there IS an antidote for cyanide poisoning, and my lab was equipped with a Lilly kit and my co-workers were quick to respond, and the chief chemist had the brains to show up at the emergency room in that poor South American town with a bottle of thiosulfate. Had the gas been H₂S instead of HCN, Argox would not be here to tell the tale. Having said that, for manufacturing HI_(aq) in quantities above 20 liters/day, this would be the most practical method. However, I repeat that H₂S is deadly poison, and if anything goes wrong, you and everybody in the immediate area will be at risk of dying. The obnoxious smell of H₂S at low concentrations quickly overwhelms the senses at higher concentrations, and it is quite common for the victim to assume that 'the smell went away, so everything's OK.' Usually the last wrong assumption they ever make...

3. React potassium iodide with ortho-phosphoric acid, recover HI_(aq) and HI. The chemistry of phosphorous is complex. Observation indicates that the following are the major reactions:

   1. KI + H₃PO_4(aq) + delta temp--> HI_(aq)+ KH₂PO₄

   2. KH₂PO₄ + KI + delta temp--> HI + K₂HPO₄
      

   3. additional HI_(aq) and HI is obtained throughout the dehydration of potassium phosphate salts and polymerization of same while reacting with potassium iodide at high temperature--400+ºC

   4. This method has the advantage of being safe and controllable and uses non watched ingredients. The process is similar to a simple distillation, and requires only the type of glassware normally owned by the clandestine chemist. For 10 liters/day of HI_(aq), this method is ideal, requiring only a 22L RB flask and heating mantle. A 12L-10L RB flask /heating mantle will produce 5 liters/day; a 5L RB flask/heating mantle 2.5 liters/day, etc. The heating mantle is a key element in making HI_(aq), oil and sand baths will not take the temperature high enough. The tweaker can use a 1L erlenmeyer with single 24/40 neck on a stirrer/hot plate combo and produce 300-400 cc in a couple of hours. (Percent recovery is a function of scale. At larger scales, more HI_(aq) will be recovered mol/mol per KI. 92% recovery mol/mol at the 22L scale and larger, contrasted with only 75% at the 1L scale. Why this is true I can only speculate, but it is true nonetheless.)

Now, for the first time on the Hive, this easy method will be explained step-by-step.

Disregard everything that has appeared previously on the Hive regarding the reaction of KI and H₃PO₄. I used TFSE extensively while initially researching this procedure, and without exception, all previous information is unclear, misleading, and, in several cases, made-up bullshit. The HI FAQ on Rhodium's page, as regards KI and H₃PO₄, is erroneous. But you can count on my write-up to tell you exactly how to make HI_(aq) safely. No bullshit here.

Here is a general overview of the procedure, specifics to follow:

In general terms, you will be mixing KI powder with H₃PO₄ liquid in a stirred RB flask on a heating mantle rigged for atmospheric distillation. The RB flask will be equipped with an condenser for downward distillation, a receiver to recover HI_(aq), and a second receiver/trap filled with dH₂O in which to bubble and recover HI.

KI will be converted first into HI_(aq), then into HI_(aq) and HI as the reaction proceeds. Hydriodic acid will distill at 105 to 127ºC. After the initial run of acid is produced and the contents of the reactor cooled, the dilute hydriodic acid will be redistilled to produce HI_(aq). The dilute hydriodic acid from the redistillation that comes over at less than 127ºC will be reused in subsequent reactions in the HI trap/receiver. No dilute acid should go to waste. Overall efficiency goes way up by recycling the dilute acid into the next batch.

If this procedure sounds complicated, it's not, and your good buddy Argox will shortly give you all the tips, short cuts, and safety considerations that you will need to successfully make HI_(aq) the first time.

Making 10L of HI_(aq) in a 22L reactor takes one full 24 hour day from start to finish. This includes setting up the glassware and dismantling and cleaning up for the next batch. You need to stay awake during the reaction. The reaction should not be left unattended for more than 10 minutes. The dynamics are continually changing as the reaction proceeds; suckback can be a concern: you need to stay on top of it. It takes the same amount of time in a [deleted], but if you have the resources and knowledge to set up at that scale, you're a master, not a student, and need no further instruction from me.

The reaction is simple. However, there are two caveats.

Caveat One--there is a white crystalline precipitate left in the bottom of the flask after the reaction is over and everything has cooled--condensed phosphates. This residue is insoluble in hot water and non polar solvents. It must be physically scraped from the flask. (Not a difficult chore with a 1L or 2 L, but with a 3N 22L RB count on breaking at least one neck. On a larger scale the problem can be solved by investing in a [deleted] with a large center flange opening that will allow you to get your arm inside and scrape.

Caveat Two--the majority of HI_(aq) is produced at a temperature above the melting point of Teflon. Teflon paddles will melt and make the phosphate residue even more impervious. Teflon stir bars will melt, revealing the magnet. But really, who cares? Don't sweat the Teflon. (After all, once that first hypothetical batch of HI_(aq) goes out the hypothetical door, you can afford to buy a $20 sheet of Teflon and cut a dozen new paddles.) Glass-coated metal rods and blades are the answer for the perfectionist in the audience. Just keep in mind that no exposed metal can be anywhere near HI_(aq). Drop one little drop on your heating mantle and watch it burn a hole through the aluminum housing on its way to China. COVER your heating mantle with foil--lots of it! That's my way of saying that freshly made HI_(aq) is very, very corrosive. So don't even think of entering the lab without eye protection, a lab coat, and good rubber gloves. If two drops of HI_(aq) can burn a serious indentation into a cast-iron lab stand base, imagine what a splash of acid will do to your skin, or worse, an eye.

PART TWO

STEP-BY-STEP INSTRUCTIONS

1. Obtain ingredients.

Ortho-phosphoric acid, (H₃PO₄) commonly called phosphoric acid, a thick clear syrupy liquid, can be purchased or ordered from the neighborhood hydroponics store. They sell it as 'pH Down.' Conversely you can order it from the chem supply. Don't respond with posts belly aching about how you're too paranoid or too smart to buy from the chem supply, and need a write-up that is 100% over-the-counter at Wal-Mart. Argox is not the guy to bitch to about chemicals not being available at the corner Circle K. He recently tried to help in that regard and only received grief for his effort. Finding chems is what separates the men from the boys, the serious from the dilettantes. Back to subject. Buy 75% technical grade phosphoric acid--this works best. Phosphoric acid is non watched and OTC. It's in everything, even Coca-Cola. Next to sulfuric acid, phosphoric is the most common acid on the planet. You can find it on the shelf at the hydroponics store. DO NOT listen to all those posts about how you can get phosphoric acid at Home Depot or the flooring company. That is bullshit. [A personal aside--I think bees should receive a rating, like on e-bay. Except it would be a bullshit rating. The more bullshit you post, the more negative the rating.] The phosphoric acid sold for cleaning tile is only 15-25% acid, the rest is water, surfactants, soap, and stuff that will fuck up the reaction. Make sure you buy 75% technical grade H₃PO₄. It is strictly OTC, so no bitching. One gallon on the store shelf retails for $us20--be sure and read the label--some 'pH Down' is nitric acid--you want the label to say 'phosphoric acid.' A 5 gallon pail can be ordered from a hydroponics store for $us65.

Potassium iodide, a heavy white crystalline powder, can be bought at the chem supply. It is non watched and non controlled. You can buy it on-line. Technical grade is OK, but most supply houses only stock the USP grade. The higher price for USP grade in the global scheme of things is insignificant, buy whatever is easiest to obtain. USP KI can be purchased for $us36/kg. There is a boom in KI these days, because of the terrorism scare, take advantage of the general panic and buy a lot if it now, you will absolutely go unnoticed. 1.3 kg of KI will yield one liter of HI_(aq) at 94% efficiency (very large scale), so order accordingly, before the WOD reads this post and adds KI to the 'List.'

2. Test ingredients.

Determine the concentration of H₃PO₄ by boiling it. Below is a chart of boiling points for different concentrations of H₃PO₄. You want yours to boil at 135º. That will indicate 75% acid. If your sample boils at a lesser temperature, don't despair, boil all your acid until it reaches 135º (and then make sure to get 75% next time). You can boil phosphoric acid in an open beaker on the hot plate. The fumes are non-toxic and non-corrosive--they smell like Sprite (because phosphoric acid is used to give soft drinks that citric flavor). H₃PO₄ is generally unreactive at room temperature--have no fear about mixing room temperature H₃PO₄ and KI in the RB flask. Nothing will happen. At room temperature, H₃PO₄ and KI will not react.

3. Mix ingredients

The mol/mol ratio of KI to H₃PO₄(100% basis) that works best, according to EXPERIENCE, is about 1:1.2. Here is how that is calculated:

1 mole KI = 166 grams
1 mole H₃PO₄ (100% basis) = 98 grams = 131 grams of 75% H< sub>3PO₄
1 X 166 = 166
1.2 X 131 = 157
157/166 = 0.946

Therefore, for every ten grams of KI, add 9.5 grams of 75% H₃PO₄. Nobody will get mad if you just add equal parts (weight/weight--w/w) KI and H₃PO₄. Now you understand how I arrived at this simple formula. Although it sounds almost flippant to say add equal parts by weight KI and 75% H₃PO₄, truth be told this formula was obtained after lots of trial and error. Adding more acid will not increase yield, but you can try it, nothing bad will happen.

As soon as I post this, three or four of the usual suspects will follow up with posts saying that I'm full of shit and that what you really need to do is add water so that all the HI will have enough water to come over at 57%. See, if you figure 1 mole of KI has 137 grams of iodine and with the one proton donated by the phosphoric acid that makes 138 grams of HI, so 138 grams of HI would need 104 grams of water to make 57% HI_(aq). Follow me? These arm-chair chemists will then tell you that the equal w/w 75% H₃PO₄ to KI only adds about 42 grams of water, therefore they will say to add 62 grams of distilled water in addition to the phosphoric acid for every mole of KI. Don't listen to them. I'm heading them off at the pass right now. The reaction just doesn't work that way. (How do I know? I thought of adding more water from the git-go and tried it. I've also experimented with every concentration of phosphoric acid from 50% to 105%.) If you add more water, you will only generate a shit load of dilute acid, which must be distilled off before the real acid is made. See, what the arm-chair chemists don't know because they haven't actually done this, is that most of the HI_(aq) comes over AFTER all the water from the 75% H₃PO₄ has distilled off. The bulk of the HI_(aq) is formed from the dehydration of 105% H₃PO₄ at high temperature, a process typical of the complex chemistry of phosphates. The H₃PO₄ actually polymerizes into long-chain 'condensed' phosphates and gives off water and donates a proton in the process. This is the water and hydrogen that make most of the HI_(aq). And those long-chain polymers are what stick to the bottom of your flask like stink on a pig. And even if I'm somehow wrong on the theory, in practice I am right on target.

Now that you know how much to add, just dump the two ingredients into an appropriately sized flask. Nothing will happen at room temperature. There is no fizzing or effervescence during the entire reaction, so you can fill the flask fairly full. But no more than 60% for a RB, less for an erlenmeyer. But you already know that, right, because you have at least rudimentary lab skills, right? There will be a period of some massive bumping at a larger scale once the water boils off and the polymerization begins, even with agitation, so if you are faint of heart, fill the flask only 30%. At 1L, 3L and 5L bumping is not a problem. The bumping is nerve-wracking at the 22L scale. At [deleted] scale the bumping will make you jump out of your fucking skin. Agitation helps but doesn't eliminate bumping altogether, so if you get scared easy, add less ingredients. It's really a function of balls versus greed. If you have the pelotas, then load that sucker up, 'cause it's a full 24 hours whether you make a little or a lot. If the doors come down, the charges will be the same, as well, so I say go for it.

4. React ingredients

UNDER A FUME HOOD, heat and stir the ingredients--it's that simple. At 65º an obvious reaction will take place. The clear solution will turn dark brown. This is hydriodic acid being formed. Keep the heat on high, don't let off. The solution will begin to boil at 105ºC and a small amount of milky white distillate will come over into the receiver.

After getting rid of the initial milky white distillate and taking up the initial bubbles in a dilute base and throwing both away, connect your two regular receivers. This is an atmospheric distillation, so relax. Just keep the heat on high and the overhead or magnetic stirring going. On a smaller scale, stirring is not necessary. For bees with big equipment who lust after the perfect yield, stir.

The reaction is not over when all the brown acid has boiled out of the reactor, it has just begun. Keep the heat on high and watch in amazement as more and more and more acid keeps forming in the condenser. Don't worry about the thermometer at the still head going above 127ºC, it is still HI_(aq) coming over, just the temp inside the reactor is getting HOT. At 400ºC both HI_(aq) and HI will come over. Lots of HI at a larger scale, so be prepared for it. About 10% of the total acid production will be in the form of HI that must be collected in the water trap/receiver. HI is exceedingly soluble in water and the dissolution is exothermic, so stirring is not absolutely necessary, but cooling is. More than 10% of the total acid comes over as HI, but most of it is being absorbed by the liquid in the receiver catching the distillate. That is why you keep the dilute acid in the receiver even after the 57% acid comes over. If you remove the initial dilute acid and then collect the 127ºC boiling fraction (HI_(aq)) as a separate fraction, then to your dismay, you will have loads of HI coming over that must be caught in water. And then you will find that the hydriodic acid in the receiver is incredibly concentrated-- 70% not 57%. The 70% acid gives off so much fumes that handling it is a challenge. So just let ALL the acid collect in the same receiver flask, make sure your receiver is big enough, and you won't have to deal with much actual HI gas.

The reaction is over when no more HI_(aq) or HI is produced. The reaction is over when no more acid drips into the receiver and/or suck-back begins to be a real problem in the water trap (suck-back with HI is violent--the most violent of any gas Argox has ever worked with, make SURE you have an empty trap to catch suck back). The remaining contents of the reactor will look like white taffy. The dilute acid in the receiver will look dark brown. The dilute acid in the water trap will be a clear brownish yellow. Once no more acid comes over, you can turn off the heat, take off the water trap, and allow the glassware to cool--slowly. Keep in mind that your glassware is at 400ºC, so don't even think about handling it or taking it out of the mantle or off of the hotplate--the thermal shock will crack the flask instantly. Since you know Argox doesn't make this shit up (unlike others, nameless for now), this means that he found out the hard way about thermal shock and cracking glassware, and is saving you a lot of grief with these words of wisdom.

5. Redistill HI_(aq)

There are two ways of telling if your acid is 57%:

1) Weigh it in a graduated cylinder--the density of 57% acid is 1.7. 500 cc will weigh 850 grams, exactly. Anything less is not 57%.

2) Boil it. 57% hydriodic acid boils at 125-127ºC.

(OK. OK. Get back on your chair. I was just kidding to see if you were awake. A little black humor--of course you don't fucking boil it, it will corrode everything in your lab including your lungs, just weigh it.)

Probably none of the initial acid collected in either of the receivers is going to be 57%. Weigh it to find out. If its density is less than 1.7, then you must redistill. No sweat. There is a short cut that makes this a snap.

The redistillation is a straitforward atmospheric distillation. No gas will be generated. As soon as the acid boils and starts coming over you must watch the thermometer at the still head. As soon as it reaches 125º, change receivers. Everything that comes over from that point forward is 57% HI_(aq). The very last drop will distill out of the boiling flask. No residue will be left, it all boils. In fact, after you have done this distillation once, you will quickly figure out the obvious short cut--collect the fraction that comes over at less than 127º, and then turn off the heat and everything left in your boiling flask is 57% HI_(aq), no need to distill it--it's already pure. Just allow it to cool before you package it up.

6. Hypothetical considerations

What follows is the only speculative part of this write-up. You might call this Argox' version of made-up bullshit. However, even my bullshit should be instructive.

How might the public view hypothetical shop-made HI_(aq)? (It depends on their intelligence, of course.) See, acid made by the method I have just detailed is dirty brown. This is due to trace amounts of HI being oxidized to I₂ as it comes over in the condenser (4HI + O2 = 2I₂ + 2H₂O) and from impurities in the tech grade KI. The brown color is insignificant, and does not interfere with the potency of shop-made acid. Commercial HI_(aq) contains a reducing agent as a stabilizer, usually hypophosphorous acid, and is clear yellow. In the hypothetical case you use this write-up for other than purely theoretical considerations, at some point the topic of off color might arise. But, again, speaking hypothetically, I would recommend that you educate rather than stabilize. Unstabilized shop-made HI_(aq) will work just as well as the store-bought variety in a hypothetical user's hypothetical application. The difference is purely cosmetic. The way to convert dirty brown acid into clear yellow acid is to add red phosphorous and heat it. But hey! Wait a minute! Isn't that what a hypothetical user might be doing anyway? Adding RP and heating it? Explain this to whomever, hypothetically. Give whoever a demonstration in a test tube. Convince them. Hypothetically.

Once the hypothetical user overcomes his or her initial reluctance, don't be surprised with the heavy pounding on the door late one night--no, it's not the cops, it might be that hypothetical person begging for more hypothetical acid. The word might hypothetically spread to others, and the all-request line become incessant. Of course, I really wouldn't know anything about any of this...it's all just hypothetical. I am making it up, OK.

As for packaging, hypothetically pour acid into amber glass bottles, or better yet, the red .....oh shit, since this is all hypothetical, I wouldn't want to be hypothetically linked to a certain bottle...hell, if you are intelligent enough to make acid, you can figure out in what to put it. Remember--one liter of HI_(aq) weighs exactly 1,700 grams. In the hypothetical case the hypothetical user goes into a production frenzy and needs volume, think black HDPE jerrycans.

HI_(aq) must be protected against light and always stored in a cool (temperature and otherwise cool) area AWAY from people. I wouldn't freeze it, but since I've never frozen any, I couldn't really say what might happen. The acid will slowly degrade over time, but no big deal. Without a stabilizing agent, HI will slowly revert to I₂. But like I said, no problem: the hypothetical user's hypothetical application will solve that hypothetical problem.

With your native intelligence, you'll figure out all sorts of other shortcuts and useful procedures in the off-chance you actually paid attention and hypothetically decide to make a little hypothetical acid.

7. Instructions for buying a new Cadillac.

What? Did I bore you, and you missed that part? You mean you weren't paying attention? Don't recall anything in all this gibberish about chemical reactions and corrosive acid that had anything to do with an expensive car? Oh. I'm sorry. In case you missed it the first time, the highly detailed instructions on how to buy a new Cadillac start at the beginning of this post, right where it says 'INTRO.'