Chemicals I Have Known (and Made) - Hydrogen Cyanide

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As I look back on my career in industry, I realize that I became inured to the chemicals I dealt with and produced. I will be posting occasionally on some of the materials I worked with and made during the first part of my career. The first chemical I worked with was hydrocyanic acid - a simple molecule consisting of a hydrogen atom, a carbon atom, and a nitrogen atom (HCN). This molecule is so simple that there are molecular clouds in space where HCN is found, released from stars that have synthesized carbon and nitrogen in their core. But HCN has a well-known reputation as a poison, one that prevents oxygenated blood from being able to deliver their life-giving load to cells. Once oxygen transport ceases, energy production in a cell stops, and the cell and the organism that contains the cell dies.


So at the chemical plant I worked at, one of the requirements to work in the cyanide area was to ensure that I could detect cyanide leaks so I would not wander into an area with a fatal concentration. This was done by means of a sniff test. Three beakers of water were set on a tray. Two were plain water, and the third had a concentration of cyanide in it that resulted in small amounts of cyanide vapor in the air above the beaker. To pass the test, you had to tell which beaker held the cyanide. The first time I took the test, I was guessing somewhat. None of this "bitter almonds" smell, just something that was a little off. By the last time I took the test, almost 10 years later, I picked up the beaker with the cyanide and before it made it halfway to my nose, I put it back down on the tray and said "That's the one." What was originally too faint for me to be certain had become so overwhelmingly repugnant over the course of a decade that it gagged me.


Cyanide. What's it good for? Hydrogen cyanide is used in quite a few chemical processes as a feed stock. One of the chemical processes is used to make another chemical called methyl methacrylate (MMA), used in acrylic paints and in plastics like Plexiglass. My chemical plant made MMA as well, but that's a story for another day. The other main use of cyanide was to make sodium cyanide, which is used in the mining of precious metals. Sodium cyanide solutions are able to leach small concentrations of gold, silver, and other precious metals out of ore, allowing it to be concentrated and extracted into product. Our plant produced sodium cyanide as well as HCN. Some HCN is shipped to other locations for use. When it was shipped, the tank cars that contained it were painted in a distinctive manner. They had red stripes on them - one that circled the car lengthwise, and one that circled the circumference of the car, forming a cross on both sides of the car where the stripes collided. These cars were called candy stripers in the trade.


Hydrogen cyanide is produced when ammonia, natural gas, and air are heated and passed over a platinum - rhodium gauze mesh. The off-gases are then absorbed, and the cyanide produced is concentrated and purified. At our plant, HCN was stored in tanks surrounded by dikes. One of our safety features was flare guns mounted on posts throughout the tank farm. If the worst happened, and liquid cyanide were to leak out onto the surface of the dike, folks were instructed to fire a flare gun and set the liquid on fire. HCN is volatile (78ºF boiling point), but the vapor will not explode. Instead, it will undergo a deflagration where the combustion wave front is slower than the speed of sound. Other gases like methane will explode, where the combustion wave front is faster than the speed of sound, which causes the pressure wave that creates damage in an explosion. So for HCN, it is much better to let it burn and eliminate the toxic vapors evaporating from the liquid surface.


One day in 1979, I was out at the plant on a Saturday. I remember that Dr. Jenks was there on that day as well, and he invited me into his office. Dr. Jenks was one of those older generation chemists who knew everything about the chemistry and processes. He had a wooden box in his office, about 18" on the narrow sides, and about 10' long. In that box was the replacement platinum/ rhodium gauze for the catalyst change. At that time, when precious metal prices were at a 30 year high, his office held about 2 million dollars in platinum and rhodium. I was impressed.


My main job in manufacturing support was in the waste treatment process. As you can imagine, the waste water from these cyanide processes needed special treatment and segregation from other waste water. The "state of the art" water collection system consisted of cypress lined trenches, with cypress boards covering the top. This ran downhill to the bottom of the plant, where we had the Trade Waste water treatment facility. Waste water came into a collection point, where sodium hydroxide was added to make sure that the water was basic. If cyanide ions were in an acidic solution, cyanide vapor would be released above the solution, and that is not a good thing. So once the pH was adjusted to make the waste basic, then it would be mixed with liquid chlorine. Our plant produced sodium metal and liquid chlorine, so we had only to send the chlorine down a pipe to the water treatment plant, and mix it in with the waste water. When the chlorine hit the basic water, it produced chlorine bleach solution (sodium hypochlorite). Bleach attacks the cyanide and converts it to a non-toxic degradation product. To ensure that the reaction took place, after treatment the water was diverted into what were called 8-hour ponds. These ponds were on either side of the treatment building, and were unlined ponds where the water was held until the reaction was complete. Then the water was released into a baffled chamber called the one hour pond where it was analyzed to make sure that all of the cyanide was destroyed, and after the last test, the water was combined with the other sewer waste and went into the City of Memphis sewage treatment system. Unfortunately at the time, our interceptor sewer did not hook up to the sewage treatment system, and the water along with all of the domestic wastewater was discharged directly into the Mississippi River. Environmental protection has definitely improved in the 40 years since I was working in this process.


I would imagine that the staffing situation for the Trade Waste process has also improved. Back when I worked at the plant, there was a single operator who was stationed at the treatment plant. This individual sat in a central control room, and on either side of the control room were the chlorine injectors with the liquid chlorine flowing through them. Now, I don't know about you, but I would be hesitant to work by myself, with cyanide-laden waters and liquid chlorine surrounding my office, but back in the late '70's, I didn't think as much about the implications of what could go wrong. The plant had a safety procedure where the person working in a remote location had to check in with the main control room at least once per hour. Believe me, at that time, so much could have gone wrong in an hour's time that the operator could have been dead for 59 minutes. But it never did at that facility during at least the first 30+ years of operation. Looking now at the facility on Google earth, it is obvious that they have made significant changes and improved the safety of the treatment operation. But some of the facilities look similar to what I worked with 40 years ago.


There's much more I could go into. Cyanide has some amazing chemistry, and the waste treatment is almost an art unto itself. I did some large-scale testing there where we added a hydrogen peroxide waste stream that was what I considered to be fun chemistry. But it was definitely a good process to work on for my first real production support for making a nasty chemical.


Posted first on my blog



Neil Lock Added Mar 22, 2018 - 12:27pm
Fascinating that a molecule so simple can be so destructive. Why?
opher goodwin Added Mar 22, 2018 - 1:34pm
When I was at school we had a chemistry teacher who loved explosives. He used gas, gunpowder and other contact explosives. He taught us how to make triiodonitrogen. It was a black paste. When it dried it exploded on contact.
We had great fun making it. We used to smear it everywhere. We put some on the roller blackboard so that when they were moved down they popped and banged. We put them under stools so that when people sat down the stools banged.
As things progressed we started using more. It can to a head when we started putting dollops around on the floor. The lab tech trod on one which exploded and he dropped a whole load of glass apparatus. We got hauled before the Head and told off. 
I think nowadays we'd probably have been locked up as terrorists.
My daughter is a chemical engineer. She works with some nasty stuff - huge containers of tons of chlorine. Enough to wipe out a city.
wsucram15 Added Mar 22, 2018 - 1:51pm
at my plant they did a cleaning and  annealing process on the metal that also included some serious chemicals.  In fact, the coating process on one form of the wire we made was all caustic materials.  Which one was used depended on electrode positive or negative.  The waste water process guy was a lazy guy, but it is an interesting process.  Thank God we had a great quality control dept.  Ive seen some interesting chemicals and how destructive they can be if not handled properly.
But my BF is the one you need to talk to about chemicals, he is a plater.  His company plates for airlines, utility companies and medical supply companies. They have big tanks upon tanks of chemicals for a variety of metal coatings,  Anodizing such as -zinc, niobium, Electroless-(i think thats hydrogen and used in nickel plating),Electroplating also a variety of metal coatings like nickel, gold, silver. etc..
the chemicals are so rough, he has to wear special clothing and boots.  It eats the material after time.
I dont think people think about this kind of thing enough. This stuff, gets dumped.  I live near an abandoned steel plant, can use the water at all..20 years later.
Dave Volek Added Mar 22, 2018 - 2:33pm
Nice essay about an industrial process. We need to better understand where stuff comes from.
The science channel has a program called "How It's Made". It keeps the various factory processes fairly simplistic. But if one has not had much exposure to industrial processes, it is quite educational.
Tubularsock Added Mar 22, 2018 - 7:52pm
Broken Clock. fascinating post. Tubularsock loved chemistry as a young child. Received his first chemistry set when Tubularsock turned eight. Started working on gun powder and developed a tidy amount and decided to fill a small rocket with it as fuel.
Tubularsock wasn’t the swiftest child on the block.
Prepared a fuse to the rocket and lit the fuse. The fuse reacted as a fuse would and all was going so well.
Then the fire hit the gun powder in the rocket and it ignited and flames shot out of the rocket and it lifted off about four inches.
At that point the rocket folded into itself and fell to the blast-off-area in a molten mass of burning goo.
It didn’t explode as expected but rather, really for a second or two, looked like a “real” rocket until melt down.
Oh Tubularsock forgot to mention, the rocket was made of plastic.
As stated before, Tubularsock wasn’t the swiftest child on the block.
Nobody's Sweetheart Added Mar 22, 2018 - 9:13pm
I made Napalm once at work, but didn't ignite it. I also experimented with making Quaaludes at the same place, but couldn't find a good guinea pig, lol.
Mark Hunter Added Mar 23, 2018 - 3:28am
When I was on the hazardous material response unit, an instructor told me that if you smelled the bitter almond scent at a cyanide incident, it was already too late for you. That never made sense to me: If you smelled it and immediately died, how did people know what it smelled like? Were somebody's last words, "Bitter almond ... ugggghhhhh"?
Anyway, I'm glad to know my brother and I weren't the only people who loved blowing things up as kids.
Even A Broken Clock Added Mar 23, 2018 - 10:29am
Neil - I can't speak about other chemicals, but cyanide affects the cytochrome C oxidase, which is the enzyme that does the transfer of the electrons from oxygen into the cell, where it is able to make adenosine triphosphate (ATP). By glomming onto the cytochrome C, it prevents the transfer from occurring. It is notable that there are antidotes available as well. We had sodium thiosulfate which if the person was still conscious you could administer by mouth (otherwise it would need to be injected). And amyl nitrite pearls (you know, the "poppers" that once were in favor as a party chemical). Those were present in enclosures throughout the manufacturing area. The biggest safety rule that we had though was the buddy system. All work was to be done by two people. The only exception was the water treatment area I described in my post.
Even A Broken Clock Added Mar 23, 2018 - 10:32am
Opher - I wonder how many folks became interested in chemistry due to teachers who were explosives enthusiasts. We also did the nitrogen triiodide, although I remember it a more purple than black. We spread it a time or two on the stairway in our high school, which did cause quite a ruckus. I also remember that later in the year, a quantity of mercury came up missing from the lab. Word was that we had a student who was trying to make mercury fulminate. Yes, it was a different world then. When my children went through chemistry, it was a pale version of what sent me into my career interest.
Even A Broken Clock Added Mar 23, 2018 - 10:38am
Ah yes, electroplating. That is also something that often uses cyanide. Cyanide ions have the ability to solubilize many different metals, and then using electricity to reverse the reaction causes the metal to plate back out on the cathode. Electrochemistry is also fascinating and I remember studying the electrochemical potentials for many different reactions.
Waste solutions from plating and other chemical processes are definitely nasty and need to be properly treated. This is one reason why regulations are so important, because before there were water treatment standards, it was definitely cheaper to dump the solutions into surface waters or down the sewer pipes.
Even A Broken Clock Added Mar 23, 2018 - 10:41am
Thanks, Dave. Before I retired, I assigned myself to write a sort of history about chemical safety where I could document some of the changes that happened while I worked. I did send a copy to my supervisor, who had zero chemical background, and left a copy with our plant's emergency response / safety team, where it probably is gathering dust. But it was a great pleasure to write these things down. I will be posting some of the process stories in my blog over time. Hope you enjoy.
Even A Broken Clock Added Mar 23, 2018 - 10:44am
Tube, that anecdote was classic. I can honestly say that I did not have a chemistry set growing up. It was only in high school that my curiosity was ignited, no ignition of rocket fuses.
I do remember though, having one of those mazes with a blob of mercury that you had to try to lead the mercury through the maze to get to the middle. We never had those for long, though. They tended to get stepped on and the mercury just sort of vanished.
Even A Broken Clock Added Mar 23, 2018 - 10:47am
Michael B, your story reminds me of my favorite professor in college, my organic professor. He was about 5'6", came into class each morning with a liter beaker of café au lait, and had a marine buzzcut. But he had such a way of explaining things that I could see the reaction taking place. Anyway, once he told us how to synthesize mescaline. He said, I'm not worried about teaching you how to do this, since you'll never get ahold of the precursor chemical that this reaction uses. So I never got to have an early turn at breaking bad.
Even A Broken Clock Added Mar 23, 2018 - 10:50am
Mark, like with opiate overdoses, people can be brought back, like with the antidotes I described. You do have some time before the ceasing of cellular processes becomes irreversible. Maybe it was those folks who were brought back that remembered the bitter almonds? As I said, though, it did not remind me of almonds.
In your volunteer fire work, do you have any opioid overdose opportunities?
Dino Manalis Added Mar 23, 2018 - 11:34am
That's why the FDA should continue to evaluate chemicals and their effects on people and the environment!
Bill H. Added Mar 23, 2018 - 11:45am
When I was a kid, I got a big foldout Gilbert chemistry set with a test tube rack and Bunsen burner. After stinking up the house by combing sulphur, iron filings, and muriatic acid, I was directed by dad to pursue other areas of chemistry. I ended up somehow becoming fascinated by growing crystals, which took much patience, but produced some really neat results. The best crystals were from nickel sulphate and copper sulphate, both of which are poisonous.
mark henry smith Added Mar 23, 2018 - 12:41pm
Thanks Opher, my brother got a chemistry set and went into the field of industrial hygiene. I believe there's a connection there. I became fascinated with making bombs out of matches and how matches could be detonated by hitting them with a hammer. And bullets, at my brother's urging.
The Burghal Hidage Added Mar 23, 2018 - 5:14pm
Chemicals I Have Known
Upon the advice of counsel I will invoke my fifth amendment right
The Burghal Hidage Added Mar 23, 2018 - 5:15pm
Marko - the old bullet with a hammer thing! Yeah, I did that too! I think there may have been chemicals involved
Leroy Added Mar 23, 2018 - 10:07pm
Thanks for the interesting narrative, EABC. 
As a kid, I had access to the World Book Encyclopedias.  I stumbled across gun power and set about making it.  My experience was similar to TubularSocks.  It was more suited as rocket fuel, but I did have one successful batch.  I spent a good chunk of the money I earned over the summers to buy fireworks, which I used to create bigger ones.  I suppose I would be under the jail if I did it today.  Probably explains why my hearing is not so good today.
Leroy Added Mar 23, 2018 - 10:21pm
My job the last year and a half with my previous employer was, in part, to deploy chemical labs in North America.  It was a learning experience.  It was supposed to be for a year and they would find another job for me.  I knew it was a lie, but I had no choice.  I would like to say that I was uniquely unqualified, but that would not be true.  My predecessor was good at deploying what was done before but wasn't qualified either.  The thought was that doing what was done before was all that was necessary--a piece of cake.  All they needed was a warm body. No one ever asked the chemical experts.  After reviewing with suppliers and asking questions, it was determined that locating hydrogen and oxygen tanks beside each other wasn't a best practice, nor was locating acids and bases in proximity with poor labeling.  The chemical expert took issue with locating the lab next to the cafeteria.  Said someone like the cooking equipment would essentially inhale the fumes, not the mention that it would stink to high heavens and would make eating there less enjoyable.  Some people are just hard to get along with.  Yeah.  It was one of those jobs that was supposed to be easy.  It was the bottleneck of the operation.  It was one of the more screwed up situations I had ever seen.
Mark Hunter Added Mar 24, 2018 - 12:25pm
Clock, I haven't run into any opiod cases personally, but it's increasing around here and some of our neighboring departments and EMS have responded to them. We're just now getting some Narcan for our first responder units, and I have a feeling we'll be using it.
Even A Broken Clock Added Mar 24, 2018 - 1:10pm
Bill - did you get hydrogen sulfide out of the mix? That would be a good indication to switch to crystals, for sure.
Even A Broken Clock Added Mar 24, 2018 - 1:12pm
Burghal - Chemicals I Have Known - the private version. Sometimes the constitution is very advantageous. Thanks.
Even A Broken Clock Added Mar 24, 2018 - 1:19pm
Leroy - thanks for your memories. There was a science fiction story (I think by Asimov) where the guilty party was identified because he put platinum black on the wrong gas cylinder. He put it on the oxygen cylinder since he had been working on Titan with a hydrogen / methane atmosphere.  Then he put it on the hydrogen cylinder, which ignited  when the cylinder was opened in an oxygen-containing atmosphere.
I also remember in my job where I had to transfer hydrogen cylinders out to air monitoring stations away from the plant. When we started, we put the cylinders in the back of a station wagon, lying on their sides. When I got better inculcated into the safety culture, I realized that driving down the road with unsecured flammable gas cylinders was not the safest thing, and I got us to use a pickup truck with a good cylinder rack. Chemicals can be very dangerous if you don't pay close attention to the safety issues with them.
Even A Broken Clock Added Mar 24, 2018 - 1:20pm
Thanks, Mark. EMS usually bears the brunt of this, but I figure that even VFD's aren't immune from having to use this as well. It's a crazy world we've created, for sure.
mark henry smith Added Mar 24, 2018 - 2:07pm
Loved that movie where they had to drive the nitroglycerine to the dam, or something, sounds like much of what I just read. They paid the drivers double, but they got blown up in the end. It was a French movie, so a Disney happy ending wasn't required, I guess.
I've worked with all kinds of idiots in the home improvement business over the years. There are products with the name Lock Tite, that if you read the label was full of acetone, and another really nasty chemical that escapes my name because of it, and guys would put themselves in rooms with no ventilation for hours on end and I think they're probably all dead now. The chemical was methaline chloride, I do believe. And who's that comedian who used to host The Tonight Show? Blond hair, husband named Fang, self-disparaging. Not Phyllis Diller, the other one. Darn lack of memory for names. I've had that problem since I was a kid, not because of chemicals. More likely concussions.
EABC, you should do a post on brain chemistry. 
Mark Hunter Added Mar 24, 2018 - 5:01pm
That was indeed Phyllis Diller, Mark, who had the husband named Fang and the wild blonde hair.
Bill H. Added Mar 25, 2018 - 11:31am
Yes, it was Hydrogen Sulfide gas. It was actually one of the written experiments in the Gilbert manual. They mentioned that not only would it stink up the house, but you would have to sacrifice a test tube for the experiment.
Even A Broken Clock Added Mar 26, 2018 - 10:18am
mark, like Mark said, it was Phyllis Diller. Started back in the sixties with her long cigarette holder while it was still socially acceptable to be seen with a smoking accessory.
Your mention of acetone brought back a memory for me. I worked for a year as an a part time chemist for a concrete company. At the time they were investigating the properties of fly ash since they wanted to use it as a cement extender. Well, I used acetone to clean off and dry off glassware. Use a spray bottle to apply acetone, then hang up the glassware on a rack and it dried off very quickly. Well, it turns out if you use a stream of acetone and aim it at a housefly in flight, the housefly instantly drops out of the sky, a dried out husk of an insect. It basically instantly dehydrates the fly. Very impressive (and addictive for a college student to try).
Even A Broken Clock Added Mar 26, 2018 - 10:21am
Bill - I think it probably was a good thing that I never did have one of those sets. Hate to think what I could have come up with when I didn't really know what I was doing.
I'm glad this stream on chemistry seems to have struck a responsive chord. I'll probably do a post every month or so on some of my other chemicals that I helped to manufacture. Each one had its unique aspects and dangers.
mark henry smith Added Mar 26, 2018 - 12:51pm
Sorry, all, the comedian I was thinking of was Joan Rivers. I got the two confused all the time.
Methaline chloride is used in paint stripper, not Lok Tite. What Lok Tite had was benzene. Guys I knew would be breathing benzene and acetone fumes all day without any ventilation. I'd tell them what I'd read on the label, and what my brother, the industrial hygienist, and immunologist mother said about those chemicals, but dudes. You tell them to read the label and they're rolling it up and smoking it. These guys would be smoking too.
I tried to keep as much ventilation as possible in my work areas. I do believe it's the reason my memory is so good, still, perhaps, except for names, and short term stuff. There's a reason they call painting, the drinker's profession in Britain. Might as well have fun killing yourself.   
Even A Broken Clock Added Mar 27, 2018 - 10:26am
Yes, methylene chloride is pretty nasty stuff. Actually, just about any chlorinated hydrocarbon has nasty properties, and can cause mental issues. Look at trichloroethane, the dry cleaning solvent. Look at carbon tetrachloride. The other thing that they do, is once they get into the ground water, they tend to segregate and float on the upper layers of the water table. Then they slowly migrate downstream. Any well water that comes from the contaminated aquifer will contain the chlorinated impurity. The compound will also migrate into surface water whenever the groundwater enters a stream. That's one reason why the sites where the contamination happened are so difficult to clean up. Just upstream of the plant I worked in here in West Virginia, there was another chemical plant that made all of those chlorinated compounds. Just imagine what was left behind from it. The site is a grassy field now, and they have some sort of pumping system to flush the groundwater out, where it will get treated, but it will be centuries before all of the contamination is gone.
Benzene smelled pretty good, but it's toluene, a derivative of benzene with a methyl group added to the benzene ring, that really smells good. Also xylene, with two methyl groups. There's a reason why they call this type of material aromatic chemicals.
mark henry smith Added Mar 27, 2018 - 1:43pm
EABC, I met a guy who would always volunteer to do the spray painting for exactly that reason, he liked the smell. I think he's dead now too. So many people I worked with in the painting field are either dead or brain dead from all of the fumes. And well water is contaminated all over. My brother would recommend a complex filtration system for any well reliant person, and keeping the system impeccably clean, since filter systems can also become a source of contaminants growing on organics. He said chlorine mixed with organics produces formaldehyde, another toxin. But made me feel better when he said the most underreported problem is micro pollutants from medicines and other sources.
What a wonderful world we live in. Without plastics, life as we know it would be impossible.
Hey, do you know what happened to the picture, Nazi, post that has like a hundred comments? Looks like it went viral. 

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