Someone rightly suggested that I started a new topic for this.
I am tooling around with the idea of adding hydrogen injection to my car and want to do so using Electrolysis of water. Or rather electrolysis of an
h2o/h2o2 solution (hydrogen peroxide diluted with distilled water for safety). I have this idea about directly translating voltage and maximum
electrode surface area for maximum extraction of H and O. However I am having trouble finding a cheap source of lab grade silver or platinum for
anticorrosive electrode material. Probably because silver and platinum arent cheap. Anyone have any good ideas about substitute electrode materials
that will resist oxidation and are easily formed into shapes unlike carbon(graphite electrodes very brittle).
Obviously Iron and Copper are useless unless I want to clean brakish redbrown or greenish byproduct every couple days.
I am also looking for an electrolyte that lacks a gaseous byproduct to electrolysis. I just want H and O escaping the reaction.
I dont need to explosively generate H. But I would be thrilled if it generated more than a liter/5-10 minutes.
There are folks sellling hydrogen injection kits for 3-4 hundred dollars that produce like a liter an hour. Which is uselessly small to enhance a
combustion reaction. Not enough hydrogen is produced in enough volume to add to the combustion reaction before recombining with the liberated O into
water. There are super expensive nickle metal hydride units that work great but they are only liberating H.
Any suggestions would be great.rsgpit - 2-6-2006 at 11:54
Just my field. I have a 1lpm electrolysis machine. I used 8 Stainless Steel grade 316 Ultra Corrosion resistant plates in parallel series. The
electrolyte is NaOH, it does not react at all. Use DC current obviously. Check out these pages and the wholes site. This guy has very good basics on
electrolysis. http://oupower.com
[Edited on 2-6-2006 by rsgpit]unionised - 3-6-2006 at 08:23
"Or rather electrolysis of an h2o/h2o2 solution "
Why use peroxide?The_Davster - 3-6-2006 at 09:34
Nickel will make good electrode material if the electrolyte is KOH or NaOH.tommyatomic - 3-6-2006 at 19:11
H2O2 is useful in a hydrogen injection system because it has extra oxygen. Producing a more complete combustion is the goal.12AX7 - 3-6-2006 at 19:36
Er...so take in more air!??
Timtommyatomic - 5-6-2006 at 00:17
rsgpit,
Good call on the 316 stainless. The spec in the wikipedia listing sounds just about perfect. Clearly I was looking way too exotic. 316 stainless is
actually pretty reasonable. And that website is pretty interesting. What kind of oxidation or rust are you getting from your electrode plates?
And NaOH for the electrolyte. His website has a handy note about it being available as drain cleaner.
12AX7,
Sure more air is good. More oxygen specifically is the goal
I can replace my stock air intake with one made to pull larger volumes of air into the engine or pull cooler air from outside the car. Alternately I
could use a turbocharger/supercharger with an intercooler to cool/compress the air coming into the engine. However the goal is the same. more oxygen.
In modern electronic fuel-injected engines the best performing engines are designed to take in as much air as possible. Furthermore your engine wants
that air to be as cold as possible because cold air is more dense and therefore contains more oxygen.
So I figure as long as I am going to end up with oxygen as a byproduct of liberating hydrogen; provided I dont explode,
how could the combustion cycle not benefit from more oxygen?gsd - 5-6-2006 at 02:21
Be aware that hydrogen has got the widest explosive limit of all substances (if I am correct then it is 4 to 74 % by volume), and this is with air,
i.e. 21% O2! Increase the oxygen percentage any more and you are literary playing with fire. Besides this oxygen will be premixed with hydrogen unlike
an IC engine where fuel is mixed with oxidizer as late as practically possible.
good luck!tommyatomic - 5-6-2006 at 06:06
GSD,
Fair enough. My plan previously was to start with distilled water H2O and then move to over the counter hydrogen peroxide which is like 3-6% h2o2 and
distilled water. Depending on the success or performance of that I was considering moving to a richer source of hydrogen peroxide as yet
undertermined. H2O2 in pure forms is actually more than significantly dangerous as well as unstable to begin with. The goal was 20-25% H2O2/ 80-75%
H2O which is actually as aggessive as I am willing to get.
Provided that the release speed is not too significant. I believe adding a frationally larger ratio of oxygen to be reasonably safe. I would never use
pure h2o2 as that is insanity beyond debate. The wikipedia writeup on h2o2 is just short of scary for anyone who can borrow an ounce of common sense.
I believe a cubic foot of H2O contains about 1,376 cubic feet of hydrogen gas and 680 cubic feet of oxygen. I am simply curious about testing an
increased ratio. I promise to post my results. If no one hears from me I blew myself up and let that be a lesson to everyone.
[Edited on 5-6-2006 by tommyatomic]rsgpit - 6-6-2006 at 09:15
Well the plates are partly rusted because I used regular tap water for some time. As you know tap water is chlorinated, and it just attacks the SS. So
if you use distilled water from the get-go, you should get little rust, as long as all the parts in the system are stainless. Why use H2O2, you're
just wasting money. It's already stoichiometric.tommyatomic - 7-6-2006 at 13:01
The why is easy. I cant find anyones published results of the benifits or performace degredation of an electrolysis based hydrogen boost system using
an h2o2/h2o mix. If someone has some experience with the benifits or drawbacks I am interested in hearing about it. Otherwise i'll just have to find
out the hard way.
So its a project and an experiment. The principal is logical but in application I would like to see first hand what the actual results are.
How can stainless steel work?
hodges - 7-6-2006 at 17:43
Maybe I'm being dense here - but I'm looking at an electrochemical series in the CRC handbook:
O2 + 4H+ 4e <--> 2H2O 1.229V
It seems to me that an electrode that will allow oxygen to form (as opposed to being attacked itself) is going to need to have an electrode potential
of at least +1.23 volts. This checks with copper, which has an electrode potential of 0.34 volts. When electrolysis is done with copper electrodes,
the copper dissolves at the anode and no oxygen is produced. The only elements it would appear would work for anodes would be noble metals such as
gold (+1.42 volts), possibly platinum (+1.2 volts), and of course inert non-metals such as carbon work. Iron, chromium, and nickel all have negative
electrode potentials. So how can stainless steel, or nickel, be used as anodes to produce oxygen?12AX7 - 7-6-2006 at 18:59
That's the reduction potential for either acid (1N?) or neutral (pH 7), and with 1atm H2 gas or something to that effect. Not much dissolves in a
basic (pH ~ 13-14) solution, I've done it myself.
Incidentially, gold and platinum probably dissolve in a chloride solution due to complexation. (I seem to remember platinum can be used for chlorate
production, so it must be able to withstand chlorides; but that it also wears at low chloride concentrations.)
Chloride, for the most part, isn't useful for oxygen anyway, since Cl2 has a lower reduction...erm...oxidation potential than O2.
Timordenblitz - 7-6-2006 at 20:24
What’s your aim in injecting hydrogen?
Are you planning on having an onboard electrolysis system, or are you trying to make it at home, compress or store chemically until injected in the
engine?
If your plan is onboard electrolysis.. you will consume more power creating the hydrogen then you get from burning it. See perpetual motion.
I really don't see an advantage of adding hydrogen to your combustion mix.
Putting lots of fuel in an engine is the easy part.. getting more oxygen in the cylinder is the trick.
Look at all the schemes man has invented for making a lot of horsepower... nitrous, cooling the induction charge, blowers, oxygenated fuels etc. It
all involves packing in more O2!
You don’t see complicated systems for introduction of more fuel. All you have to do is jet up.
If you succeed in injecting hydrogen in your engine without having a way of simultaneously shutting off the gasoline flow, your mixture will go rich
thus reducing power and efficiency.
Adding more fuel requires adding more oxygen. You’ll then need a blower or nitrous injection working in conjunction with the hydrogen injection.
With such a setup, having poorly sealing valves, hot spots, incorrect timing or a back fire happen... say good bye to your intake system.
In my opinion burning hydrogen is good for the environment, not drag racing.tommyatomic - 8-6-2006 at 12:06
My project never involved drag racing or anything that silly.
I was however considering onboard electrolysis and I am quite familiar with the absurd notion of perpetual motion.
I am quite aware that no system is more than 100% effecient and most systems arent even 30% effecient. Hell the most effecient alternater I can
install in my car isnt even 65% effecient.
Its easy enough to put less fuel in the engine by using smaller injectors. The goal is to test running cleaner and try running less petrol.
No need to drag perpetual motion kooks into this. Its simply a chemical curiousity of the mechanical variety.
[Edited on 8-6-2006 by tommyatomic]Twospoons - 8-6-2006 at 14:32
Well you are not going to run less petrol, thats for sure. Since petrol is the only energy input to your system, and you are planning on converting
some of it to hydrogen by electrolysis at an overall efficiency of around 10% ( Otto cycle engine = 40%, alternator = 60%, electrolysis = 50% - and
I think those are fairly generous figures!), you can see that you are going to need a lot more petrol to get the same mileage out of your car. I'm
fairly sure hydrogen will burn hotter too, which will push up NOx emmissions.hodges - 8-6-2006 at 14:49
Quote:
Originally posted by 12AX7
That's the reduction potential for either acid (1N?) or neutral (pH 7), and with 1atm H2 gas or something to that effect. Not much dissolves in a
basic (pH ~ 13-14) solution, I've done it myself.
Tim
Thanks. I learned something. I just tried electrolyzing a NaOH solution using ordinary copper wire. I did in fact get quite a bit of bubbling at
the anode, unlike when using a salt solution. I knew concentration affected potential, but I always thought the effect was negligable. However I
guess if the pH goes from 1 to say 14, that's a 10^13 factor difference in OH ion concentration which is such a large difference that the potential
change with concentration becomes significant.neutrino - 8-6-2006 at 18:40
There seems to be some confusion around. Please answer one question tommy: where is the power from the electrolysis cell coming from?tommyatomic - 9-6-2006 at 06:30
initially from a 12v dc lab power supply. I would like to run it off of my 12v marine grade deep cycle battery so it would be powered seperately from
the auto.tommyatomic - 9-6-2006 at 06:41
Even if it were running off of the auto's power (not my plan at this point) it would be not be any less effecient than the civic that belongs to the
guy living next to me. It has a 600 watt 8 channel stereo. It produces enough noise to product base tone shockwaves in nearby buildings. Locating a
surplus of power to run something like this is a relative non-issue. Stereo installers find ways to power stuff like this all the time.neutrino - 10-6-2006 at 22:46
Full power is being produced by the alternator continuously regardless of how much is actually needed? I didn’t know that.
I think you’ve fallen into the trap laid by the media that hydrogen is some wonder fuel. Let’s get this cleared up here once and for all.
<b>Hydrogen is not a power source!</b>
Hydrogen is a store of energy: you need energy to make it and get energy back when you consume it. You can only get out of it what you put in.
(That’s the law of conservation of energy.) Even then, there are huge efficiency problems with hydrogen.
Electrolysis is (IIRC) ~10% efficient and running the hydrogen you make to the engine will give you around the standard 30% of that. So you will only
get 3% of that extra stereo energy back into the engine if you do install a hydrogen generator on your car. Add in the extra weight of the equipment
needed and the cost of the parts and installation and I seriously doubt you can even break even.12AX7 - 11-6-2006 at 07:36
Quote:
Originally posted by neutrino
Full power is being produced by the alternator continuously regardless of how much is actually needed? I didn’t know that.
Where'd he say that?
I also read he's powering the hydrogen from an independent power source. That much sounds good.
Tim12AX7 - 11-6-2006 at 07:43
Quote:
Originally posted by neutrino
Full power is being produced by the alternator continuously regardless of how much is actually needed? I didn’t know that.
Where'd he say that?
I also read he's powering the hydrogen from an independent power source. That much sounds good.
Timtommyatomic - 11-6-2006 at 20:46
I dont know what there is to get irrational about.
I never said that H = power. Its just extra fuel with unique combustion properties. It may cause the ecu in the car to wig out. No telling what the
car will do. Although I am curious to find out.
This is no sort of attempt at perpetual motion and neither I nor anyone else has claimed that any auto can produce enough H or O to sustain a
combustion cycle independantly. It cant. I am quite aware.
My plan is to power the electrolysis independant of the alternator. I am not even done with my test electrolysis rig. Although I am almost there. I am
working out the plumbing.
I am curious to see if I can run my auto cleaner. I already understand the rules. The laws of thermodynamics are not generally ever flexable. They
cant be bargained with. They cant be reasoned with. Its no mystery.cbfull - 26-6-2006 at 14:30
Quote:
Originally posted by tommyatomic
In modern electronic fuel-injected engines the best performing engines are designed to take in as much air as possible. Furthermore your engine wants
that air to be as cold as possible because cold air is more dense and therefore contains more oxygen.
I'm not sure this is correct. Yes, the air is slightly more dense (but not by any great amount), but there is a thermodymic property here that is
more important.
Cold air tends to literally suck the energy out of your combustion reaction. If both the fuel vapor and air are very hot when the reaction is
triggered, you will be much closer to getting the maximum amount of energy possible for that reaction.
I haven't done these kinds of calculations for many years so anyone please chime in if there is something I am forgetting.franklyn - 26-6-2006 at 18:14
Practically anything you may want to know on this subject
[Edited on 27-6-2006 by franklyn]Twospoons - 27-6-2006 at 17:23
Quote:
Originally posted by cbfull
[
Cold air tends to literally suck the energy out of your combustion reaction. If both the fuel vapor and air are very hot when the reaction is
triggered, you will be much closer to getting the maximum amount of energy possible for that reaction.
No, thats not true. You still get the same delta T, if mass and fuel energy are the same. BUT the potential efficiency is higher if the whole process
runs colder. Engine efficiency on Wikipedia
If you look at the efficiency eqn for a non-reversible heat engine you can see that n will be higher as Tc/Th gets smaller. This can be
rewritten as Tc/(Tc+deltaT). If deltaT is fixed by the energy input and mass of the system, the only way to increase efficiency is to make Tc smaller
(ie colder!)
In fact I think it was NASA developed an engine running on liquid Nitrogen (cold store) and atmospheric heat (as a heat source) and they acheived an
efficiency of around 77%!tommyatomic - 29-6-2006 at 08:30
I think the issue with temperature in an internal combustion engine generally revolves around predetonation. "High performance" engines run on premium
fuel. Premium fuel is less explosive. Not more. This is done to prevent predetonation and increase timing and compression.
I believe H being used in an internal combustion engine would have to be done at cooler temperatures(not cryogenic temps) in order to produce best
power output at best effeciency. The more explosive the fuel(more power) the greater the issue of predetonation.franklyn - 6-7-2006 at 21:38
