megalomania
June 26th, 2003, 11:47 AM
the_wingman
Frequent Poster
Posts: 48
From:
Registered: JAN 2001
posted March 27, 2001 10:22 AM
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I often fill firecrackers or rocket engines with a mixture of sodium chlorate and sucrose. When I bought a bag of pure glucose some time ago I thought this would give me a better and faster burning fuel. But I was wrong.
Why on earth glucose burns slower than sucrose? Glucose molecules are smaller than sucrose ones.
Does sb has a helping advice?
firebreether
Frequent Poster
Posts: 109
From:
Registered: NOV 2000
posted March 27, 2001 02:32 PM
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a couple things, it is the particle size not the molecule size that makes it faster. The molecules of one kind clump together to form bigger particles. if you pulverize these then they become smaller and it will burn faster. Two, sucrose probably has more energy in it then glucose. This extra energy may cause it to burn faster. These are just guesses. The most likely scenario is maybe you did something that made it that way. Sucrose is easier/cheaper to get anyway so why do you care? Also maybe glucose is more hygroscopic than sucrose, although that is probably not it since NaClO3 is even more hygroscopic than either.
Mr Cool
Frequent Poster
Posts: 991
From: None of your bloody business!
Registered: DEC 2000
posted March 28, 2001 04:19 PM
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Sucrose will have roughly double the energy of glucose per mole, but a mole of sucrose is roughly twice as heavy as a mole of glucose, so the energy per gram should be nearly the same.
It might have been damp, or maybe the proportions were wrong. However, due to the fact that sucrose is a larger molecule, it is more likely to decompose when heated because it will jiggle around more than glucose. And in order to react and burn, the molecule will need to decompose. So, glucose might have a higher activation energy, which means that less energy will be released overall.
Personally, I don't like chlorate/sugar mixtures. Try KClO3/charcoal, in a 3:1 ratio, corned with a bit of dextrin as a binder.
the_wingman
Frequent Poster
Posts: 48
From:
Registered: JAN 2001
posted March 30, 2001 10:19 AM
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Thanks, I never tried this composition.
Do you use normal BBQ charcoal or activated coal, and how do you make dextrin?
blackadder
Frequent Poster
Posts: 313
From: London
Registered: DEC 2000
posted March 31, 2001 04:45 AM
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Wingman, you shouldn't use BBQ charcoal OR Activated Charcoal, as both are shit. You should have a go at making your own, or buying some off pyrotek or skylighter. The charcoal needs to have some Hydrogen and Oxygen impurities to work well.
[This message has been edited by blackadder (edited March 31, 2001).]
firebreether
Frequent Poster
Posts: 109
From:
Registered: NOV 2000
posted March 31, 2001 10:53 AM
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the_wingman - describe how you use the SC / sucrose rocket engines. Do they work well?
Anthony
Moderator
Posts: 2321
From: England
Registered: SEP 2000
posted March 31, 2001 03:09 PM
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SC/sucrose is not very good for rocket motors, they often explode.
the_wingman
Frequent Poster
Posts: 48
From:
Registered: JAN 2001
posted March 31, 2001 03:40 PM
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Well, this is true.
Therefore I use sodium chlorate only as an additive to increase the burnig rate of saltpeter/sugar rocket fuel.
Since rocketry is quite new for me I haven't been able to try the melting method yet.
Frosty
A new voice
Posts: 28
From:
Registered: DEC 2000
posted March 31, 2001 03:40 PM
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You can make dextrin by baking cornstarch 4-6 hours in the oven at 220 to 240 degrees. I got that off of J's site.
Frequent Poster
Posts: 48
From:
Registered: JAN 2001
posted March 27, 2001 10:22 AM
--------------------------------------------------------------------------------
I often fill firecrackers or rocket engines with a mixture of sodium chlorate and sucrose. When I bought a bag of pure glucose some time ago I thought this would give me a better and faster burning fuel. But I was wrong.
Why on earth glucose burns slower than sucrose? Glucose molecules are smaller than sucrose ones.
Does sb has a helping advice?
firebreether
Frequent Poster
Posts: 109
From:
Registered: NOV 2000
posted March 27, 2001 02:32 PM
--------------------------------------------------------------------------------
a couple things, it is the particle size not the molecule size that makes it faster. The molecules of one kind clump together to form bigger particles. if you pulverize these then they become smaller and it will burn faster. Two, sucrose probably has more energy in it then glucose. This extra energy may cause it to burn faster. These are just guesses. The most likely scenario is maybe you did something that made it that way. Sucrose is easier/cheaper to get anyway so why do you care? Also maybe glucose is more hygroscopic than sucrose, although that is probably not it since NaClO3 is even more hygroscopic than either.
Mr Cool
Frequent Poster
Posts: 991
From: None of your bloody business!
Registered: DEC 2000
posted March 28, 2001 04:19 PM
--------------------------------------------------------------------------------
Sucrose will have roughly double the energy of glucose per mole, but a mole of sucrose is roughly twice as heavy as a mole of glucose, so the energy per gram should be nearly the same.
It might have been damp, or maybe the proportions were wrong. However, due to the fact that sucrose is a larger molecule, it is more likely to decompose when heated because it will jiggle around more than glucose. And in order to react and burn, the molecule will need to decompose. So, glucose might have a higher activation energy, which means that less energy will be released overall.
Personally, I don't like chlorate/sugar mixtures. Try KClO3/charcoal, in a 3:1 ratio, corned with a bit of dextrin as a binder.
the_wingman
Frequent Poster
Posts: 48
From:
Registered: JAN 2001
posted March 30, 2001 10:19 AM
--------------------------------------------------------------------------------
Thanks, I never tried this composition.
Do you use normal BBQ charcoal or activated coal, and how do you make dextrin?
blackadder
Frequent Poster
Posts: 313
From: London
Registered: DEC 2000
posted March 31, 2001 04:45 AM
--------------------------------------------------------------------------------
Wingman, you shouldn't use BBQ charcoal OR Activated Charcoal, as both are shit. You should have a go at making your own, or buying some off pyrotek or skylighter. The charcoal needs to have some Hydrogen and Oxygen impurities to work well.
[This message has been edited by blackadder (edited March 31, 2001).]
firebreether
Frequent Poster
Posts: 109
From:
Registered: NOV 2000
posted March 31, 2001 10:53 AM
--------------------------------------------------------------------------------
the_wingman - describe how you use the SC / sucrose rocket engines. Do they work well?
Anthony
Moderator
Posts: 2321
From: England
Registered: SEP 2000
posted March 31, 2001 03:09 PM
--------------------------------------------------------------------------------
SC/sucrose is not very good for rocket motors, they often explode.
the_wingman
Frequent Poster
Posts: 48
From:
Registered: JAN 2001
posted March 31, 2001 03:40 PM
--------------------------------------------------------------------------------
Well, this is true.
Therefore I use sodium chlorate only as an additive to increase the burnig rate of saltpeter/sugar rocket fuel.
Since rocketry is quite new for me I haven't been able to try the melting method yet.
Frosty
A new voice
Posts: 28
From:
Registered: DEC 2000
posted March 31, 2001 03:40 PM
--------------------------------------------------------------------------------
You can make dextrin by baking cornstarch 4-6 hours in the oven at 220 to 240 degrees. I got that off of J's site.