I had to fill the car with petrol the other day. I also filled my 20 litre jerrycan for all the petrol driven things around here – generator, mowers and the brushcutter (AKA The Petrol Driven Bastard). The only unleaded petrol available here now is the new E10 – ten percent ethanol.

The car’s fine with it, almost all Toyotas have no issue with this silly diluent. Saving emissions? You really need a bit of chemistry education – what do you get when you burn ethanol? The generator and mower are also fairly new so I don’t expect them to have problems. My little tractor – the ride on mower – might, and the Petrol Driven Bastard (PDB) certainly will.

So I’ll have to get the ethanol out or at least reduce it for those things. It’s not difficult but it will reduce the octane rating of the remaining petrol by, as far as I can find out, 3 points. It’ll drop from 97 to 94 octane, I doubt the old engines will notice that.

I am not going to do it for the car because I’d have to deal with 50 litres at a time and the car doesn’t need it anyway. The PDB declares alcohol-free petrol essential and I expect the old engine in the tiny tractor will need it too, but I only have to deal with a couple of litres for both.

It’s very simple. Ethanol is soluble in water. Most of the hydrocarbons in petrol are not. So you mix the petrol with water (for E10 I’d say 1 part water to 9 parts petrol), shake the hell out of it and leave it overnight. You’ll have the water (and hopefully most, if not all, of the ethanol) at the bottom and the petrol at the top. Oh and… don’t be tempted to have a smoke around it. Shaking it is going to release a lot of explosive fumes. Probably best to not do it in the kitchen, eh?

This is easier if you have a garage full of lab equipment including a separating funnel and stand but you can do it in any petrol resistant container. If you can tap off from the bottom, take out all the water and a bit of the petrol just to be sure, and dispose of it without killing anything that matters to you. Do not attempt to drink the ethanol/water mix, you don’t know what else got extracted. Dump it. Ideally not into the sewage system and certainly not into your septic tank. I have a lot of weed-strewn waste ground here that would be improved by a treatment with something horrible, you have to find your own way.

No separating funnel, you could carefully pour or siphon the cleaned up petrol into another container. Make sure you only get petrol and sacrifice the last bit, don’t try to get it all or you’ll get water in there again.

This works if you only need a litre or so for an old, small engine. It’s not viable for a very old car engine. That would need a whole industrial scale fractionation column and I don’t think many people will have space for that – or sufficient training to use it without blowing themselves into mince.

This E10 is not about saving the planet. Burning ethanol produces carbon dioxide, same as pretty much every chemical compound on the planet. It’s about getting rid of old cars. They want you to drive electric dodgems that won’t work in winter or in floods.

There is a solution, if you have the equipment and knowledge. Unfortunately modern education has ensured that few people have that knowledge.

I am increasingly convinced that this has happened before.

21 thoughts on “E10

  1. Early 80s – Shell introduced low octane petrol without telling anyone. Result? Lots of blown engines because nobody had been told to retard the ignition to cope, made worse by older engines’ tendency to be running high compression ratios to suit leaded. Byebye, piston crowns . . . I don’t know if anyone sued them successfully – probably not because they would lawyer up and had the money to do it indefinitely.

    Liked by 1 person

    • Hmmm… in the early 80s I had an old Austin Princess (the wedge shaped one) that blew a piston so badly I had to get a new (well, scrapyard new, I was a student) engine fitted. I hadn’t heard about this low octane change until now.

      Liked by 1 person

    • I hope it’s effective on a particular weed patch I have here. Nothing else has managed to shift them. So if I can get ethanol-free (or at least much reduced) petrol and kill some persistent weeds at the same time, excellent.

      Liked by 2 people

      • Well, ammonium sulphamate (eg Rootout or suitable generic) used to be permitted for weeds, brush and tree stump removal. EU regs now only permit it for tree stump removal. Cheap enough and highly effective.

        Liked by 1 person

        • I do have some tree stumps I’d like to take out. They tend to be hidden in the grass so they catch the scythe, which can be unpleasant. I’ll see if that stuff will help.


  2. The process of producing the alcohol will produce CO2.
    Carting it about will produce more.
    There is a similar scam with deisel. Mix it with subsidised palm oil.
    Then the Beeb bleats about natural habitat being destroyed so that Eastern farmers can grow more subsidised palm oil.
    But the greenies at Beeb will tell you that the palm oil is for cooking. As if the world is suddenly having more fry ups.
    Do not tell you that over half the world palm oil production is for adding to diesel as a sustainable, renewable, etc. To save the planet.
    Bugger the endangered species in what was jungle, rainforest whatever.
    I think that Denmark no longer catch sand eel, food of the endangered cute puffin, to burn their little fatty bodies as renewable sustainable fuel in power stations.
    Now they make margarine and animal feed from them. And they hog and increase their EU quota for sand eel. Wonder why your Danish bacon tastes odd? Or your soft spread Lurpak.
    Probably used to lubricate their wind turbine gear boxes.
    At least the whales are safe,, for now. It was Scottish shale oil that saved the whale. Bings.
    Now we want to bugger up their acoustic and electro-magnetic navigation and comms equipment with ultra sonic noise from offshore wind turbines and all the electric cables lying on shallow sea bed. Know how ship de-gausing works. Think about that over thousands of square kilometers.
    All to save the planet.
    End of rant.

    Liked by 4 people

    • I guess they produce it by fermentation which will produce a lot of CO2 as it runs. Then they have to distill it, which requires heat (more energy, more CO2). And that’s just the start.

      Like hydrogen, ethanol is not a primary energy source. It has to be made from other energy sources, using energy and generating CO2 in the process. And then you burn the ethanol… which produces CO2.

      So it’s clearly not about CO2 production at all. It’s all about separating dopes from their money.

      Liked by 3 people

  3. Thank you for this. I had completely forgotten about my rather ancient Hayter mower with a Briggs & Stratton engine, with all this talk of E10. Normally, when it’s getting near empty, I just take my old petrol container with us when my wife fills her car and top it up with the same unleaded stuff. This only happens every couple of years or so.
    The Government website has nothing about lawnmower compatibility.
    Next time we go to the petrol station, I’ll check to see if they have super unleaded available – if not I’ll have to follow your instructions.

    Liked by 2 people

  4. If the alcohol is 10% by volume, as opposed to 10% by mole ratio, that’s even worse. If, to a first approximation, unleaded 95 is all octane (C8H18, molecular weight = 114) and alcohol is all C2H5OH = 46, then if we assign 0.9 of a mole of octane present instead of 1 mole, that’s replaced by 114/46 moles of ethanol which is just shy of 2.5 moles. Octane’s combustion enthalpy is -5074 kJ/mol, whereas ethanol’s is -1367 kJ/mol. They are thus, substituting (from 1 mol octane to 2,5 mols ethanol) 3376 kJ instead of 5074. Could someone else check my figures, just to make sure?

    Liked by 1 person

      • Exactly. It’s like the “eco” dishwasher setting
        that ffing setting doesn’t clean anything so it’s not eco if you’re running the machine twice. (I tend to put everything through the 65 degrees . Pasteureises everything

        Liked by 1 person

        • I’ve wondered about the eco push to wash everything at 30C. That temperature doesn’t kill any bacteria, it incubates them. Sure, soap will wash some of them off (it won’t kill them) but any that are left will be thriving.

          Liked by 1 person

  5. I think it’s important to say something about hydrogen as a supposed combustion fuel here. People in the media and on social platforms are periodically in fits of exultation about it.

    My refutations are below:-

    (1) Hydrogen is // not // a common element on Earth; the main and functionally the only sources are (a) water, and (b) natural gas and the lighter alkanes/paraffin fractions. See (2) below, for a process that’s far far cheaper and more convenient…

    (2) Hydrogen is nowhere made industrially by the electrolysis of water; this is only seen in the chemistry labs of such schools as still have them. Trouble is, it looks so tidy and you see pretty little bubbles and stuff, and it makes journos wet themselves with delight… The process is //astoundingly// expensive in electrical power – even if you tried to do it via “renewables”. A current of 200,000 Amps (yes, I did type 200,000) will give you just under a cubic foot of hydrogen gas (not liquid…) even second. That’s _ 2 grams _ …) You need about 40 grams (20 seconds’ production to even start to equal the heat output of a mole of petrol (as octane C8H18), for which there are no special safety measures needed as it’s a fluid at room temperature, whereas hydrogen would have to be delievered compressed or as a liquid. Explosion risks etc.

    It is made on hundred-million-tonnage+++ scales by the sysnthesis-gas/producer-gas processes; these involve reacting steam and methane/ethane at temperatures above 750C in the gas phase. The stable oxide of carbon above 700C is carbon monoxide (NOT CO2!) and this can be piped straight to blast furnaces as the prime reducing agent for smelting iron our of its ores. The hydrogen produced goes mainly to the Haber process, for making ammonia, the critical reactant in fertiliser manufacture.

    (3) No electricity generating method iis very efficient. To make hydrogen from water, you’d need first to generate the electric power, then convert it to DC via AC-to-DC rectification (you can’t electrolyse stuff form AC mains), and then you have to store/compress/ transport safely the hydrogen. You still have the compression/transport problem if you make it via the methane/steam processes. This is why all the plant for this is less than a couple of hundred yards from the steam-reformer towers to the Haber-Process reactors. You just have a furling or so (or less) of piping.

    I’ll think of more, later…


  6. I’ve read that one of the ways of filtering out watery contamination in petrol, is to pass it through a filter made of (clean) chamois leather. Might be worth a try to see if it works for you Leggy.


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