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galveston
Jul 10, 2009, 10:04 AM
I need for some chemist to answer the above question.

I ask because I know from personal experience that a mix of gasoline and propane will not burn (in an ic engine, at least), and I am thinking about running a genset on a mix of propane and hydrogen.

I wouldn't want to start the project if there is some reason that the two gasses will not work together.

Perito
Jul 10, 2009, 10:07 AM
I need for some chemist to answer the above question.

I ask because I know from personal experience that a mix of gasoline and propane will not burn (in an ic engine, at least), and I am thinking about running a genset on a mix of propane and hydrogen.

I wouldn't want to start the project if there is some reason that the two gasses will not work together.

Gasoline will not react with propane. They will not burn unless there's oxygen available. There will be a critical amount of oxygen (the explosive limit) below which combustion is impossible.

Unknown008
Jul 10, 2009, 11:23 AM
And to answer your question, no, propane does not react with hydrogen under normal conditions. However, I think that if you're using propane in a genset, that'll work fine. I doubt if the hydrogen would react with propane, but both would burn in the engine, provided that there is sufficient oxygen like Perito said.

galveston
Jul 10, 2009, 11:24 AM
My brother had Mercury with a dual fuel set up. A switch would change from gasoline to propane, but if he was running on gasoline, he had to shut off the gasoline and let the carburetor run dry before turning on the propane or the engine would shut off just like turning off the ignition.

You may be right, but you would think that with a big 4 barrel carb, there would be enough air to cause combustion.

Can you tell me anything about the hydrogen and propane though?

(Sorry, your post just barely got in before mine.)

Unknown008
Jul 10, 2009, 11:34 AM
That's OK galveston :)

Propane is a saturated hydrocarbon and does not react readily. It can burn and react with halogens (like chlorine, bromine, etc) under certain conditions. Being saturated, it cannot react with hydrogen.

If it were to be propene, then, it would have reacted with hydrogen to form propane. Propene is an unsaturated hydrocarbon, and is saturated when reacted with hydrogen.

(I'm a scholar, sorry if there may be things that I may have unconsciously mentioned which are not the case in practical)

galveston
Jul 12, 2009, 11:54 AM
OK then Jerry. Thanks.
So it would appear that the propane and hydrogen would not mix well.

But if they were both introduced into an engine with added air, would there be combustion of both, or would there be a cancellation or limiting factor to combustion?

Perito
Jul 12, 2009, 01:12 PM
I think you've misunderstood this.



So it would appear that the propane and hydrogen would not mix well.


They will not react when mixed.



But if they were both introduced into an engine with added air, would there be combustion of both, or would there be a cancellation or limiting factor to combustion?

There will be combustion of both. There will be nothing limiting combustion -- if you provide sufficient air.

I'm not sure why you would want to burn a mixture of both.

Propane is a hydrocarbon (a saturated hydrocarbon, meaning it has no double bonds), C3H8. Hydrogen is H2. Propane will burn to form CO2 and H2O, carbon dioxide and water. Hydrogen will burn to form H2O. Propane can be liquefied (pressure and); hydrogen cannot -- at least not at normally achievable temperatures. You might have difficulty adding the mixture of the two compounds in a controlled manner. That's the only thing I think you'll have trouble with.

galveston
Jul 12, 2009, 01:34 PM
I think you've misunderstood this.



They will not react when mixed.



There will be combustion of both. There will be nothing limiting combustion -- if you provide sufficient air.

I'm not sure why you would want to burn a mixture of both.

Propane is a hydrocarbon (a saturated hydrocarbon, meaning it has no double bonds), C3H8. Hydrogen is H2. Propane will burn to form CO2 and H2O, carbon dioxide and water. Hydrogen will burn to form H2O. Propane can be liquefied (pressure and); hydrogen cannot -- at least not at normally achievable temperatures. You might have difficulty adding the mixture of the two compounds in a controlled manner. That's the only thing I think you'll have trouble with.

Thanks. That is what I need to know.

I want to generate electricity for my house using as much HHO as I can get from electrolysis of water. If I can't get enough to actually run the engine, I hope that I can supplement propane enough to make it economically feasible. The engine would burn as much HHO as available and then use propane to make up the rest of the required fuel.

Perito
Jul 12, 2009, 01:52 PM
I want to generate electricity for my house using as much HHO as I can get from electrolysis of water.


What power source are you using to electrolyze water? If that power is solar, for example, you could probably use that power more directly with less loss than trying to convert it to hydrogen and then back to water via combustion. The laws of thermodynamics are pretty clear on that.



If I can't get enough to actually run the engine, I hope that I can supplement propane enough to make it economically feasible. The engine would burn as much HHO as available and then use propane to make up the rest of the required fuel.

I hope that was a typo. HHO is H2O, water. You can't burn HHO.

Unknown008
Jul 13, 2009, 05:59 AM
Oops, I didn't know you posted back galveston... I didn't get a notification... :(

Both would burn yes, but they do not react together as Perito said. Also, I don't quite understand why you are burning hydrogen. If you come to have it as a by product, then it's OK. There are engine that use hydrogen only. A good example is in space shuttles. Using only hydrogen as fuel, they get plenty of energy and the fuel is lighter compared to the hydrocarbons that would produce the same amount of energy.

galveston
Jul 13, 2009, 11:01 AM
What power source are you using to electrolyze water? If that power is solar, for example, you could probably use that power more directly with less loss than trying to convert it to hydrogen and then back to water via combustion. The laws of thermodynamics are pretty clear on that.



I hope that was a typo. HHO is H2O, water. You can't burn HHO.

Maybe it should be HOH, the product of electolyzing water. Hydrogen and oxygen. There are a lot of people experimenting with this and are finding ways of using less electricity in the process. Right now there are cars running this gas to supplement gasoline and getting improved mileage. One company sells units for autos that are claimed to produce 2 liters of gas per minute without using large amoiunts of electricity.

I remain hopeful that this may be the answer to the reduction of fossil fuel use.

But at any rate, thanks to all for answering my question.

Unknown008
Jul 13, 2009, 11:07 AM
Electrolysis of water gives H2 and O2. :confused:

Electrolysis of water - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Electrolysis_of_water#Equations)

galveston
Jul 13, 2009, 12:54 PM
Electrolysis of water gives H2 and O2. :confused:

Electrolysis of water - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Electrolysis_of_water#Equations)

Ummm, not arguing, but how can that be? Where does the extra atom of oxygen come from?

Unknown008
Jul 14, 2009, 07:03 AM
What happens is (if you checked the full equation)

2H_2O \rightarrow 2H_2 + O_2