Hello,
I was wondering if any of you Ladies and Gents might be chemists, industrial or otherwise. I am looking into a project (actually a thought experiment at the moment) that uses a chemical reaction/process. I need to fully understand that process and reaction so that I can design a piece of equipment to optimise and make best use of it.
All help gratefully received.
Cheers,
Carl.
And the reaction is .
Sorry about that, it comes from years of applying a “credentials before essentials” mindset.
I’m interested in two things. The first is the catalysing of 35% hydrogen peroxide with sodium permanganate, in either solid form or in solution, to produce steam and oxygen. I’m hoping that this can be used as an instant source of drive gas for a small turbine. This has been done in rocket engineering, most notably by the Germans in ww2, but they used 80% or stronger peroxide. I judge those kinds of concentrations way too dangerous. So I need to know what kind of a reaction I can expect from 35%. How hot will it get? How much steam? What concentration of permanganate solution?
The second thing is the reaction between ethylene gylcol or glycerine and pottasium permanganate. This is almost a hypergol, i.e. mixtures combust virtually instantaneously on contact. Similar questions apply. How hot? How much gas? What are the constituents of the gas produced? Again I’m looking at this either as a turbine drive gas generator or a possible igniter for a larger rocket engine.
Thanks in advance,
Carl.
I said sodium and pottasium permanganate in the above post. I meant either or in both cases.
I went straight to IGNITION! by John Clark (download and view in a dedicated reader if your browser makes a mess of it), which has a whole chapter on the stuff but there’s nothing to read about low concentration peroxide. This raised a smile though
Say that somebody dropped (accidentally or otherwise) a greasy wrench into 10,000 gallons of 90 percent peroxide in the hold of the ship. What would happen —and would the ship survive? This question so worried people that one functionary in the Rocket Branch (safely in Washington) who had apparently been reading Captain Horatio Hornblower, wanted us at NARTS to build ourselves a 10,000-gallon tank, fill it up with 90 percent peroxide, and then drop into it —so help me God —one rat. (He didn’t specify the sex of the rat.) It was with considerable difficulty that our chief managed to get him to scale his order down to one test tube of peroxide and one quarter inch of rat tail.
The whole book’s a fun read if you’re interested in “exciting” chemistry 
From memory the British version of the meshersmit rocket engine used a platinum catalist and I think that it is now declassified and the since museum has one to look at.
Why use a solid fuel when peroxide engines can be so simple?
The British engine was much better and didn’t blow up all the time
Rates of reactions is a bit complicated and it was a long time ago I will try to look at it over the weekend
Rates of reactions in a rocket engine is a bit complicated and it was a long time ago I will try to look at it over the weekend.
My initial guess would be about 1/4 of the power if you went 35% proxide
I can see that I will need to provide a bit more background so that we don’t end up going over well trodden ground.
I’ve read Ignition; you have to take everything the Americans say about peroxide with a whole mine full of salt. After WW2 we in this country became the world authority on catalysed peroxide engines. In 1971 we launched a satellite, Prospero, using the Black Knight rocket powered by Bristol Siddeley Gamma engines. These catalysed peroxide (90%) through silver plated gauzes and then injected kerosine into the superheated steam and oxygen stream that resulted.
In 1988 David Andrews, one time chief engineer of the Gamma project wrote in a JBIS paper on Black Knight that:-
With regard to silver or silver nitrate as a catalyst, I’m trying to avoid this as it is very expensive. The Germans used a 27% solution of sodium permanganate in water to catalyse hydrogen peroxide in the steam generator of the V2 missile. Steam generator output drove the turbine that ran the pumps for the fuel and oxidiser, namely LOX and ethanol. An excellent description is given in the report on Operation Backfire, downloadable from the Smithsonian.
To reiterate, I’m looking at a slower, more modest scale reaction using the 35% peroxide which is much safer to handle. I’m hoping I can make a unit that could drive a small turbine to give usable power.
I’m also very interested in the ethylene or propylene glycol/permanganate reaction. A good rocket engine igniter could lie in the idea of injection of glycol and permanganate solution, the flame from which could then ignite the main propellants.
Operation Backfire was the British Technical Intelligence effort to analyse and test the V2 rocket. German technical units were rounded up and with assistance from British (mostly REME) units, they assembled and test fired a number of V2’s. The report runs to 5 volumes. Volume 2 contains the engineering report on the design, construction and operation of the missile. The detail is breathtaking.
It is indeed one of the sorriest facts in the history of human endeavour that such a groundbreaking technical feat will forever be tainted by it’s association with Nazism.
100ml of 35% (weight/weight) solution is 38.5g of H2O2, that’s 1.13 moles (say about one).
Based on the reaction 3H2O2 + 2KMnO4 → 3O2 + 2MnO2 + 2KOH + 2H2O.
One mole of H2O2 and 104g of KMnO4 gives 11.88g of water.
Not sure if that is of any help?
Thanks Jan!
Now we are getting somewhere. I have been doing this myself, looking at the molar quantities and the energy released by the reaction between H2O2 and KMnO4. WHat I’m trying to get to is the amount of heat released and the temperature this would take the water to when converting it to steam.
Carl.
Another one for you. What alchemy is required to get hydrogen peroxide out of sodium carbonate peroxide? This is commonly sold as Vanish detergent and from chemical suppliers.