question: catalytic heater materials
joe_m...@my-dejanews.com
I want to get some information on the materials and construction of a
catalytic heater element, like those found in propane tent heaters or in
butane soldering irons, you know the type. Is the wire mesh at the barrier
of combustion made of anything exotic, or is it just some corrosion resistant
mesh? Could it possibly be NiChrome, tungsten, or some other hi-temp metal?
Some folks have indicated that it might be platinum or palladium, but I can't
really see that considering how inexpensive these things are. I've seen
similar devices used at Greek fast food places where they have these vertical
heaters glowing away cooking the Gyro stuff. That's sort of in the direction
I want to head. However, those ones sometimes seem to be little more than
just perforated sheet metal (stainless steel maybe?)
I am looking to build 4 small(ish) natural gas catalytic heads (about 3
inches diameter), and I thought I might solicit this list before I go
burning up a pile 'o stuff (my time included).
Please post your reply to j...@ciddev1.tor.ec.gc.ca
All suggestions are appreciated! Regards, Joe M.
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Don Foreman
behind a stainless (?) screen -- as in a thermal bugfogger. The screen
glows, emits radiant heat. The catalytic ones are platinum or palladium
based, I think. The difference is that with a catalytic element, there is
no flame, per se; oxidation happens at the surface of the catalytic
element without an open flame. I built a thermal bugfogger using the first
scheme, using fine-mesh stainless screen from a surplus store. The screen
was a cylinder with steel caps on the ends, a regular propane torch head
poked thru a close-fitting hole in one end cap.
Surrounding that is a coil of steel tubing (brakeline) thru which the fog
oil goes to be heated. When I light it, blue flame flicks around the
outside of the screen for a while till it gets hot and starts to glow;
then the combustion moves "inside", the sound changes, and it is ready to
start fogging. Open flame would ignite the fog, but once it gets cookin'
the flame is completely contained within the screen. I don't claim to have
invented this -- it's a copy of a commercial unit I thought was too pricey.
Works like magic on the 'skeeters "up north".
I think the broilers in some gas ovens work this way also.
Sources for catalytic material would include the tent warmers, Jon-E hand
warmers. I've seen catalytic screens for kerosene heaters for about $7.50
that work pretty well -- finishes the combustion process so they don't
stink. Might be able to scrounge catalytic material from catalytic
converters from the junkyard, but I don't know what form it takes.
joe_m...@my-dejanews.com wrote in article
<6p264b$9qi$1...@nnrp1.dejanews.com>...
Steve Rayner
catylist.
joe_m...@my-dejanews.com wrote:
: Hello all,
: I want to get some information on the materials and construction of a
: catalytic heater element, like those found in propane tent heaters or in
: butane soldering irons, you know the type. Is the wire mesh at the barrier
: of combustion made of anything exotic, or is it just some corrosion resistant
: mesh? Could it possibly be NiChrome, tungsten, or some other hi-temp metal?
: Some folks have indicated that it might be platinum or palladium, but I can't
: really see that considering how inexpensive these things are. I've seen
: similar devices used at Greek fast food places where they have these vertical
: heaters glowing away cooking the Gyro stuff. That's sort of in the direction
: I want to head. However, those ones sometimes seem to be little more than
: just perforated sheet metal (stainless steel maybe?)
: I am looking to build 4 small(ish) natural gas catalytic heads (about 3
: inches diameter), and I thought I might solicit this list before I go
: burning up a pile 'o stuff (my time included).
: Please post your reply to j...@ciddev1.tor.ec.gc.ca
: All suggestions are appreciated! Regards, Joe M.
: -----== Posted via Deja News, The Leader in Internet Discussion ==-----
: http://www.dejanews.com/rg_mkgrp.xp Create Your Own Free Member Forum
--
Steve.
Visit my website at:
http://www.victoria.tc.ca/~ud233/homepage.htm
************* Tu ne cede malis, sed contra audentior ito. ****************
******************************** - Virgil ********************************
******Yield thou not to adversity, but press on the more bravely.**********
Ed Blessman
process, but very reliable.
Does anyone remember what material used to be used in the mantles on camp
lanterns burning white gas? I recall that they changed material because the
original was toxic. But it was efficient. Isn't that the way.
If you are going with an IR system look at using ceramic plates instead of
metal mesh. My garage heater works well using this principle.
James Wilkins
> For the Pt to work catalyticaly it must be 'blacked'. It is a messy
> process, but very reliable.
> Does anyone remember what material used to be used in the mantles on camp
> lanterns burning white gas? I recall that they changed material because the
> original was toxic. But it was efficient. Isn't that the way.
I think they used Rare-Earth oxides, like Cerium, Lanthanum, maybe a
little Thorium, etc. Supposedly the radioactive impurities evaporate
within the first 15 minutes.
Plain old Calcium oxide, from garden lime, glows -very- brightly when
heated.
jw
Ted Edwards
> ...
> heated.
Thus the term limelight.
Ted
Ted Edwards
> If you are going with an IR system look at using ceramic plates instead of
> metal mesh. My garage heater works well using this principle.
Could you describe that heater in more detail please?
Ted
Bevis
I used to buy for recycling catalytic converters from cars and processed some
as well . Actually the amount of platinum used is rather small its only added as is
done for some lab uses as for example a small volume of platinum chloride was added
to asbestos and then heated to reduce the platinum to metallic fine particles again
with a much larger amount of asbestos than platinum so as to keep it inexpensive .
In pure powder form i often amuse my friends by blowing methyl alcohol fumes from a
small piece of tissue over the platinum and it will heat up instantly and glow red
hot very neat for hand warmers if you don't mind or can deal with the tendency to
form formaldehyde . Lately I have been thinking about making a small nitinol or
biometal motor using this property for super small fuel powered motors they have
been using batteries . Yes I think you might be able to recycle the platinum from
old ones , I know the catalyst can become poisoned and I assume this could happen
with old heaters and recycling renews it .but it might be to difficult for you . I
know I could but it might be to much typing for a process you might not want .
However you can buy platinum chloride but be prepared to pay 10 or 20 times the
market value of the platinum if from a lab supplier , its why I always save some of
my metals . But do try some of the companies that buy precious metal scrap as I
have gotten excellent buys in such metals for example tantalum for 40.00 per pound
, and dissolve the platinum in your own aqua regia , its slow but will dissolve .
Repost with any extra questions on how to do this if you need to
gad...@nbnet.nb.ca
Sincerely Dale
>
>
> : I want to get some information on the materials and construction of a
> : catalytic heater element, like those found in propane tent heaters or in
>
dan
> > lanterns burning white gas? I recall that they changed material because the
> > original was toxic. But it was efficient. Isn't that the way.
> ...
>
> I think they used Rare-Earth oxides, like Cerium, Lanthanum, maybe a
> little Thorium, etc. Supposedly the radioactive impurities evaporate
> within the first 15 minutes.
>
> Plain old Calcium oxide, from garden lime, glows -very- brightly when
> heated.
> jw
once used for bright stage lights, thus the term "lime light".
--
It's not what you know,...
it's what you know that's not so.
Ted Edwards
> scheme, using fine-mesh stainless screen from a surplus store. The screen
How fine?
> Surrounding that is a coil of steel tubing (brakeline) thru which the fog
> oil goes to be heated.
What moves the oil? What is the oil? How does the heated oil leave the
tube? Perforations?
Ted