lnstantkarma Posted November 21, 2007 Posted November 21, 2007 I've been trying to learn the chemical action that it uses to deepen the color of a flame. The resources that I have found so far only write about the history of chemicals used as chlorine donors. If it helps I use parlon, I just really want to know because I know how everything else in my compositions work.
asilentbob Posted November 21, 2007 Posted November 21, 2007 A chlorine donor is simply some compound, usually organic with -Cl groups... The chloride salts and chloride species that form at high temps in the conditions of combustion generally have a better emission spectra for pyro purposes. For instance CuCl gives a better deep blue than CuO... infact according to IPP CuO actually gives a weak red. Also yes, thats Cu(I) instead of Cu(II). This isn't necessarily the rule, it just generally happens with the metals we use... I'm sure some metals out there give worse emission spectra as their respective chlorides. And freaky species can form that don't look possible like SrCl... we all know Sr is 2+... however it is created in passing in the extreme environment of flames... So... you want a blue star... you either use CuCl2, which will decompose into CuCl in the extreme enviroment... or you use CuO and a chlorine donor... then the Cl (or HCl) and CuO react forming CuCl2, or directly CuCl due to the extreme enviroment... or you use CuCO3 and a Cl donor in the end reaching the same CuCl... Via IPP pg.144:(AND already on The Pyrotechnic Workshop Reference!!!)(As is linked to in my signature!!!)SrCl deep redCuO weak redSrOH orange redCaOH orangeCaCl orangeNa yellowBaO dull yellow greenCuOH pale greenBaCl deep greenCuCl deep blue or violet blueKCl pale violetSrCl + CuCl purpleAl2O3 black body radiatorMgO black body radiatorMgCl transparent The forum is not a substitute for google/rec.pyrotechnics!
Mumbles Posted November 21, 2007 Posted November 21, 2007 Heres a table from Hardt that gives some spectral lines from the various emitting species in a more precise fashion than from IPP. http://www.apcforum.net/Mumbles/Hardt.jpg
crazyboy25 Posted November 21, 2007 Posted November 21, 2007 what does a black body emitter look like? i have heard of them like black strobes but does anyone have a pic/video?
deadman Posted November 21, 2007 Posted November 21, 2007 I was also under the impression that chlorine salts specifically Magnesium are a clear gas at the temp the star burns and doesn't cloud the light/color.
Mumbles Posted November 21, 2007 Posted November 21, 2007 Black body is at times a confusing term. It doesn't always mean no radiation out. The term black body means it absorbs all electromagnetic energy it recieves, and emits none. The property of absorbing all EM energy, makes them good thermal indicators. Seeing a piece of metal glowing red in a fire and knowing it's at around X temperature is an example of thermal indication of black bodies. It is an odd term, as both the salts in question are pure white, and are therefore subject to another set of rules, sometimes called white body to some. Basically emissivity equals absorbtivity. IE they emit over all wavelengths essentially. Long story short, they are bad in pyro. The wash out colors. Incidentally, they are also what give that extra bright whiteness to flash and such. If you measured it, a pure red flash comp would have less intensity than a white one.
brok3n Posted January 26, 2008 Posted January 26, 2008 I was always interested if something like Trichloroisocyanuric Acid could be used as a donor. Or PVC from pipes - or if it could be synthed from PVA.
Arthur Posted January 26, 2008 Posted January 26, 2008 Pipework PVC will probably be 60% PVC and gave lots of inhibitors and fillers in the mix also once it is compounded to a rigid material extrusion the PVC will be too soft to grind to dust. Trichlor isocyanuric acid easily found in the swimming pool chemical shops, unfortunately for us dissociates on contact with moisture to give free chlorine which will,in water, form HOCl chlorine bleaching agent. This is fine in pools but free chlorine forming inside a firework liberating HOCl would also liberate other things in a potentialy energetic misture.
asilentbob Posted January 26, 2008 Posted January 26, 2008 my still in the works website:Pyrotechnic species like SrCl that are not common under normal conditions must be formed in the pyrotechnic reaction. The chlorides of many metals seem to give more desirable colors than the lone metals usually do. I was about to say that I don't know why... However... Given that metals are black body radiators as they are getting burnt up... and/or their oxides are black body radiators... their chlorides are not... they are much more specific in the light that they radiate when they are excited then return to a ground state... so it makes sense. Or in my current mental state it seems a perfectly reasonable explanation. Its like Mumbles said with the iron bar analgy. When its heated up it gives off many many many different wavelengths of light, this holds for many metals and their oxides, where-as compounds like SrCl and CuCl tend to give only certain bands of color. my still in the works website:MgO(s) + C(s) ---> Mg(g) + CO(g)MgO(s) + HCl ---> MgCl(g) + OH-(g)Both of the above can happen to prevent MgO from sticking around. For this reason color stars using Mg often have extra carbon or extra chlorine donor. (Since MgCl is "transparent" probably meaning that the light it gives off tends to be somewhat out of our perceivable range)
Mumbles Posted January 26, 2008 Posted January 26, 2008 ASB, I don't know if I can completely agree with that last quote of yours. The key is to completely avoid the formation of MgO and Al2O3 in the first place. I mean obviously it can't be 100% efficient, but it is desired to keep it to a minimum. The idea behind carbon is to eat up any excess oxygen around. If you did the stoiciometry on some good color stars, you'd probably find that it is oxygen deficient, balanced to CO or some fractional oxygen percentage in COx. It also has the added benefit of smoothing out the burn in small quantities. The extra Cl is to ensure both full production of the color producing species, and to form MgCl in flame. Which you are right about, is pretty much transparent in the flame. I want to say it produces UV light though. Excess Cl content just makes sure it all gets formed.
flamingape Posted May 5, 2008 Posted May 5, 2008 asilent bob answered a few questions i have but there certainally are others... I am wondering why i cant get my donors to burn green or blue in black powder. I dont have access to chlorates or perchlorates (although I will appeal to sky lighter) and the cell route is a real pain in the in the vagina on the bills. I have been making all my color donors. CuCl recrystallized on coffee filters with a green mix of Al and CuOH was the only thing that worked. great colored fuse my other mixes just dont like to light
asilentbob Posted May 5, 2008 Posted May 5, 2008 I'm a bit confused by what your trying to do in your post... but... KNO3 isn't a great oxidizer for colors, its usually used in just black powder and similar star and fuse comps where color isn't needed, it may be contaminated with calcium, sodium, and other ions in your case too... It should still make great black powder... but there are reasons its pretty much never in color star comps. Charcoal naturally gives off black body radiation when its burned up. Its not the best choice for colors, though it could and does work in some situations. Many sulfurs are contaminated with CaCO3 and clay, but this doesn't really hurt its use in BP. I'd recommend that you don't order any chlorates just yet. Wait until you have more experience. While CuCl2 could be considered a chlorine donor... its really starting with the chlorine already and doesn't need to donate it at all... What kind of ratios are you trying? Did you write down the formulas you made? Since your using potasisum nitrate rather than potassium perchlorate, the colors are going to be less impressive if they show at all.
flamingape Posted May 17, 2008 Posted May 17, 2008 nah i wasnt writing down my ratios, i started with my coffee blender BP ive been using for rockets and went from there... if you would be kind enough to share some of these KNO3 color comp I'd be in your debt for sure! information on KNO3 color comps are virtually non existent so far as i can discern on the internet would you be willing to upload or point me towards the pyrotechnia series as im seriously having trouble finding anything but the "whistles" part of IX. and how much more experience would you say i need before you think im ready for working with chlorates?
50AE Posted May 17, 2008 Posted May 17, 2008 (edited) MOD EDIT: Off-topic to this post, and removed. Please feel free to post your question in the Random Thread. It's much more likely to get an answer there than here, given the Topic title. Thank you. Edited May 17, 2008 by TheSidewinder
TheSidewinder Posted May 18, 2008 Posted May 18, 2008 Flamingape, While I cannot answer your first questions, I can answer the last one in general. If you have actively been making pyrotechnic devices such as: stars used in shells (and the shells themselves), star mines, colored fountains, etc for at least a year, then you are PROBABLY experienced enough to start working with Chlorates. (However, it's important to remember that "experience" does not necessarily equal "knowledge".) Chlorates are a class of oxidizers that all have some "special handling and manufacturing" requirements, and it is beyond the scope of a single post to address those requirements. I'd strongly suggest that you search the forum and read EVERY post that you can find which address the use of Chlorates, and cautions thereof. They're not any more dangerous than any other vigorous oxidizer, but they DO require that you keep them away from a number of other common pyro chemicals. Cross-contamination can lead to some VERY unpleasant consequences. Hope that helped, and I encourage you to keep learning. Even the Masters (of which I am most certainly NOT one) will tell you that you never stop learning. TheSidewinder
asilentbob Posted May 18, 2008 Posted May 18, 2008 Sorry, the only KNO3 color comps I know of would be oranges and whites. Barium nitrate and strontium nitrate on the other hand are in a few comps that work ok without perchlorates if I remember correctly.
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