Nitric acid and phosphoric acid

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Simon007

Well-known member
Joined
Aug 28, 2016
Messages
54
Hi there, ok a little story, at work one of the engineers was told to clean some blocked water nozzles from the ovens, they are made of brass and get scaled up due to the hard water we have here, anyway he was told to use this chemical in the sonic bath, so he did and as soon as he put the nozzles in, brown fumes appeared, when he told me this, I thought that sounds like nox fumes, so I went to look at this chemical and it's from ecolab and the msds states that its a cleaning product and contains nitric acid >20 <70% and phosphoric acid <10%, now the company won't use it, so the question is, can I use it for refining? Will the phosphoric acid affect it's use?

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Personally, I would forget it, depending on the composition of the chemical there is a slight possibility it could be converted to nitric acid with much trouble and research, but I would forget, not worth the trouble. it besides if the company will willingly provide you with chemicals tell them to buy you nitric acid without additives.

I would just make a trip to town to my local auto parts and feed store, and make my own nitric if It was too far to go to buy it or I could not get nitric acid.
 
Problem is in the uk it is impossible to get nitric acid without a licence, also sulfuric acid is also hard to get at 98%, yes you can get battery acid but it's low concentrate, also sulfuric drain cleaner but the quality isn't that great.
If it was as easy as asking work to buy nitric acid, I would of! Problem is like I said, to buy nitric you have to have a licence, even companies, I doubt they could buy this cleaner again, it has been hanging around in the chemical shed for a while.

Dam terrorists spoiling everyone's fun, also with a stupid kid throwing acid in a load of people last month in London, that will probably make it difficult to buy anything.

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Post the MSDS and a picture of the product maybe we can help.

I have made good strong nitric acid from battery acid, nitrates are all around you (Heck your pee could be made into nitric with a lot of work and time), even a caveman can make it from rocks H2SO4 and dirt from the cave floor KNO3, countries, kings, and governments have power through history because of nitrates, nitrates are all around us, countries used to tax their population being paid in nitrates from the farmers, there is a way to find a source for nitric, no matter what country tries to stop you, you just have to learn and figure out how. they are used all around you in some form or another.

There deliming solutions that I know of, that contain up to about 30% nitric acid and as much as 40% phosphoric acid (normally the nitric is very dilute say 5%, with phosphoric acid being the major component of the deliming solution. used for cleaning plumbing, food and dairy equipment... Primarily to remove calcium and magnesium salts, phosphoric acid is used to passivate the Iron alloys against corrosion by the dilute nitric acid.

Some delimers even have additives like hydrochloric acid which may cause problems for making nitric (for silver for example).

Some delime solutions also use hydrofluoric acid which is fairly volitile something we would not be wanting to mess around with here.

Phosphoric acid can be used in distilling nitric acid, whether you can from the chemical you have may depend on its composition.

Phosphoric acid is pretty much a non-volatile acid (boiling point above somewhere above 300deg. F), that can displace NOx from a nitrate salt. Phosphoric acid can also be concentrated by evaporation (much like nitric acid can up to its azeotropic composition with water around 68% HNO3), only phosphoric can be made much stronger I believe somewhere around 80% (if My memory works, which is not very good).
 
Ok here is a picture of the container
And the msds
cf0e04955903d234211b427fbff3647d.jpg
View attachment UK-EN-105522E-P3-HOROLITH FL.pdf

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Simon007,
Have you read the data sheet?

Have you taken notice of the dangers involved with its use?

These dangers can be even worse when you start using these acids (especially nitric with the metal of the periodic table), many of which we deal with in recovery and refining of precious metal.

From the ingredient stated on the MSDS, it does appear the product can be made into nitric acid, that is as long as there are no chemicals or additives that are not listed on the MSDS, which possibly could interfere with making HNO3.

From what I can gather from reading the MSDS, you have 20% HNO3 and 10% H3PO4, which should be able to make a weak HNO3 of less than 20% (water from the process).

Keep in mind if you had a gallon of the delimer solution, holding somewhere around 70% to 80% H2O, and less than 10% is H3PO4.
There would also be some loss of the nitric (unconvertable NOx) in the process of making it into the very dilute nitric acid ( less than 20% HNO3 in concentration).

Now before attempting trying to extract the nitric from solution. As you noticed when you read all of the warnings in that MSDS (if you have not studied it you should now).

You will also need to do a thorough study, in order to be able to protect yourself from the dangers of the gases created from the acid.

We have a fairly good safety section you can get a basic knowledge of some of the dangers of the gases, and how to protect yourself from them, you should also do your research on the web for the dangers of NOx gases, and safety precautions.

After you have done your research on the dangers of the gases and handling acids.

We can begin to discuss the dangers involved with the process of extracting the nitric acid from the solution.

For example:
From the simple mistake of lowering the temperature of the reaction vessel, or a power outage lowering the temperature of your reaction vessel, and having extremely hot boiling acids ( say 68% nitric acid mixed with 90% phosphoric acid) and sharp shards of your extremely hot lab glass exploding in your face, from doing some simple thing like turning off the heat, and getting blinded for life.
 
Thanks for the reply butcher, yes I completely understand the dangers of the chemicals we use, and I understand the chemical used at work, which is why I said to my manager that they can't use that chemical for what they where using it for, I also downloaded the msds for it and told him what was produced when they put brass in it and showed him the dangers of NOx which is why it has been hidden away, he did say to pour it down the drain! Imagine what my response to that one. I will take it home so that can't happen, I suppose I could use it to remove base metals.

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Simon

Looking closely at the MDS sheet it appears that the Nitric content is a minimum of 20%. The actual statement says 20% - <70% i.e. It could actually be as high as 69% although that may not be likely.

It's certainly pretty corrosive and good enough to use for stripping base metals, but try it in a very weak solution first having checked the relevant metal reactions with the Phosphoric acid (freely available on t'interweb.) I do think that I would personally feel comfortable trying a very small amount as an experiment as an AR solution, but be sensible, careful, and use all the relevant protection.

I really do mean small amounts in a controlled environment to make sure it doesn't have any side effects. You know the drill with safety by now. Plan, research and cover your bases before you pour a drop. If you don't feel prepared, or have enough safety systems or equipment then put simply don't do it. It's gotta be your decision.

Jon
 
Hi Jon,

Yes the msds is vague on the nitric, well I saw what was left of the brass water nozzle! I will see how it works at getting rid of base metals and have a go at ar with it, also I have a lot of silver mylars and silver contacts from contactors, so I'm sure it will be useful to me.

Simon

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Hello Jon,
Chemicals llike these are very common in the dairy industry and I use ecolab's other cleaning products at work making cheese daily. The nitric acid in it is usually on the low side of the range in the msds (but not always!) so titrating it is necessary before considering it. The Phosphoric acid can damage your glassware if exposed or heated for long enough. It will dissolve base metals and can make a weak AR that will dissolve gold.
The problem is what is not shown in the msds. I tried a very similar cleaner once and could not see the reaction so I kept adding more and more only to find it also had an anti-foaming agent added. It made the bubbles microscopic so I couldn't tell when the reaction had started or ended other than color change. That additive is not classified as hazardous so it isn't on the msds. I meet with the Ecolab Rep weekly and asked him about it and he told me there are many propreitary additives they use (but not what they're made of)
So not knowing what is in your particular solution sounds pretty risky.
Stay Safe. Good Luck
 
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