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megalomania
June 17th, 2003, 08:38 PM
fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 05-29-2001 05:03 AM
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can anyone tell me if this reaction is true, does it work ?
NH4NO3 + KCl -> NH4Cl + KNO3
because i need tons of potassium nitrate and i have lots of fertilisers [NH4NO3 100kg , KCl 80kg]
i thinks thats a cheap method of making KNO3, tell me if i'm wrong

- stilzchen -



Agent Blak
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Posts: 766
From: Sk. Canada
Registered: SEP 2000
posted 05-29-2001 10:07 AM
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just to bad it won't form a ppt. they both been alkaline are souble no matter what they are linked with.
Thanx for coming out eh.
------------------
A wise man once said:
"...There Will Be No
Stand Off At High Noon
... Shoot'em In The Back
And, Shoot'em In The Dark"

Agent Blak-------OUT!!



PHILOU Zrealone
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Posts: 479
From: Brussels,Belgium,Europe
Registered: SEP 2000
posted 05-29-2001 10:44 AM
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To reply to you we need the solubilities (saturated solutions) in grams per littre at 0C and at 80C of KCl, KNO3, NH4Cl and of NH4NO3!
------------------
"Life that deadly disease sexually transmitted".
"Chemistry is all what stinks and explode; Physic is all what never works! ;-p :-) :o)"



fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 05-29-2001 03:50 PM
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so, here are the solubilities (saturated solutions) in grams per littre at 0°C and at 100°C of KCl, KNO3, NH4Cl and of NH4NO3.
[sorry i didn't found it by 80°C but from KCl and NH4Cl i found it]
0°C 100°C 80°C
NH4NO3 118,0g 871,0g ?
KNO3 13,0g 246,0g ?
NH4Cl 29,4g 77,3g 65,6g
KCl 27,6g 56,7g 51,1g


I hope its helpfull - sorry about my ... english

- stilzchen -

[This message has been edited by fire stilzchen (edited June 02, 2001).]



PHILOU Zrealone
Frequent Poster
Posts: 479
From: Brussels,Belgium,Europe
Registered: SEP 2000
posted 05-30-2001 10:44 AM
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Following what you have written it should work wel!
But it is a lot of work!
First take 200g of NH4NO3 in a volume of 1 liter (complete with water!) heat this until 20C-25C under stirring everything should dissolve!Continue the stirring with an addition of 55g of KCl! Heat until 100C (the solution must be clear no cristals in it so heat a little higher if needed until clear)!Then cool the mix down fast until 0C!A precipitate of KNO3 will occur!
To assert this I have used your datas!
MMNH4NO3= 80g/mol
MMKCl= 74.55g/mol
MMKNO3= 101.1g/mol
MMNH4Cl= 53.45g/mol

Solubilities in mol/l of:
NH4NO3:
at 100C= 10.8875
at 0C= 1.475

KCl:
at 100C= 0.7605
at 0C= 0.3702

KNO3:
at 100C= 2.4332
at 0C= 0.1285

NH4Cl:
at 100C= 1.4462
at 0C= 0.5500

From this you can see that KCl is (slightly) less soluble than NH4Cl at all temps!
That NH4NO3 is the more soluble of all at all temps!
That KNO3 is the less soluble at 0C!
Knowing that the less soluble salt will drive the precipitation prior to all the others salts!
At 100C you can't go over 56-57g of KCl because it is the less soluble salt at that temp (by security I have put 55g)!
I have also used the rule of common ion (by adding a slight excess of NH4NO3:
when in a saturated solution of a salt another common ion enters the system the solubility of the first salt decrease following the solubility equilibrium constant(Ks(T))!

Thus following those laws:
Ks(KNO3)(at OC)= (conc K+)exp1 *(conc NO3-)exp1
=(0.1285)*(0.1285) (in a pure water solution)= 0.01651 sqre mol/sqre liter
Here we have 200g/l NH4NO3 and thus 200/80 mol/l NO3(-)= 2.5 mol/l nitrate anion!
And 50g/l KCl that makes 50/74.55 mol/l K(+)= 0.6707mol/l potassium cation!
Multiplying those two numbers we have the Ks'(at OC) value =2.5*0.6707 sqre mol/sqre l = 1.6767 sqre(mol/l)
Since this value is 100 times much over the permitted solubility we will have a precipitation of nearly all the permited KNO3
Then the remaining conc of K(+)= Ks(OC)/2.5 mol/l NO3(-)= 0.01651sqre(mol/l)/2.5 (mol/l) = 0.006604 mol/l and we had 0.6707mol/l potassium cation in solution thus we precipitate 0.6707-0.006604 mol/l of KNO3= 0.664096 mol/l!
This means 0.664096 mol/l * 101.1g/mol= 67.14g of KNO3!

After collecting those batches it is a good idea to recristallise them via the same process (since some KCl may coprecipitate-not a lot): saturation at 100C then fast cooling to 0C!

Thus to make 670g you would need 10 liters of the above mix of 2000g NH4NO3/500g KCl!
Enjoy!


------------------
"Life that deadly disease sexually transmitted".
"Chemistry is all what stinks and explode; Physic is all what never works! ;-p :-) :o)"



Agent Blak
Frequent Poster
Posts: 766
From: Sk. Canada
Registered: SEP 2000
posted 05-30-2001 02:03 PM
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what about this. Calcium nitrate is avaible as a fertilizer also, it also will arose less suspician than asking for NH4NO3. you could use a Rx that would look like this and would even give you a ppt.
Ca(NO3)2(sol) + K2SO4(sol)--->2KNO3(sol) CaSO4(ppt.)
That should work unless I am over looking something.
------------------
A wise man once said:
"...There Will Be No
Stand Off At High Noon
... Shoot'em In The Back
And, Shoot'em In The Dark"

Agent Blak-------OUT!!



fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 05-30-2001 03:37 PM
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thanx,
in germany its hard to get calciumnitrate as fertilisers. so i buy ammoniumnitrate in 100kg in "czech land".
PHILOU where do you learned to calculate the reactions so good ?
- fire stilzchen -




Jumala
Frequent Poster
Posts: 200
From: Germany
Registered: OCT 2000
posted 05-30-2001 08:24 PM
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The solubility table is fine.
I looked for it several time because I need it to calculate the kalkammon salpeter quantity in a saparation process.
But pure AN would be better. What quality is your AN from czech rep. ?
In germany it should be possible to get KNO3 as food additional under the E252 number.
At Ebay someone sells this KNO3 in 1,5 Kg bags with 99,5% purity.
But I don´t know the damn source.


PHILOU Zrealone
Frequent Poster
Posts: 479
From: Brussels,Belgium,Europe
Registered: SEP 2000
posted 05-31-2001 05:49 AM
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I'm a chemical engineer in chemistry and biochemistry specialised in organic chemistry! I was a chemistry autodidact, so I knew a lot about nearly everything before starting my 5 years university!I never read books(I find them borring), except science ones (I can stay hours reading them!)!

------------------
"Life that deadly disease sexually transmitted".
"Chemistry is all what stinks and explode; Physic is all what never works! ;-p :-) :o)"



fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 05-31-2001 03:41 PM
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my AN from czech rep. is 17%NO3 and 17%NH4. i never found a code like 34-0-0 but 17%+17%=34% so i think its a good stuff. the smoke bombs with AN + newspaper are very nice they smoke very well and sometimes when the smoke bombs are too hot they will fizz and burn very fast.
also i tried to make ammonpulver and it worked.
a 50kg bag was 8$[usdollar]

- fire stilzchen -



Jumala
Frequent Poster
Posts: 200
From: Germany
Registered: OCT 2000
posted 05-31-2001 11:44 PM
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Hallo Philou,
do you mean you read absolute no books or only no books like KIPE.
I bought "Nitroglycerine and Nitroglycerine Explosives" by Phokion Naoum (450pages) some weeks ago.
It is really interesting to read about old techniques in every detail. The book is original from 1923 but still up to date.

The Ammoniunnitrate from Cz is 34-0-0.
AN = NH4NO3 = 17% +17%
8$ for 50Kg is really cheap. Especially when no separation is nessesary. Is it prilled (little pearls) or cristallized.

Perhaps you can get nitromethane also in Cz?





PHILOU Zrealone
Frequent Poster
Posts: 479
From: Brussels,Belgium,Europe
Registered: SEP 2000
posted 06-01-2001 03:17 AM
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I just meaned I read only science books...all the rest is crap to me (when reading those poetry, love stories,...books, it feels like loosing time!).
So everyday my science knowledge grows more and more!
------------------
"Life that deadly disease sexually transmitted".
"Chemistry is all what stinks and explode; Physic is all what never works! ;-p :-) :o)"



fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 06-01-2001 11:23 AM
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the czech AN is prilled but i never asked for nitromethane because the name of the chemicals are different, so nh4no3 is azotan.
in poland the names like the czechs and the price is allmost the same.
can i ignite natriumchlorate with electrical power like a car battery? and can i use it to let ANFO or ANNM go off?
in 1 or 2 days i'll send you a link with pictures from one of my 50kg AN bags.

- fire stilzchen -



Lagen
Frequent Poster
Posts: 174
From:
Registered: MAY 2001
posted 06-01-2001 09:33 PM
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Agent Blak: That Rx works, just the K2SO4 is a pain to dissolve. It's best to boil it. This way you can get a very pure product even without recrystallization, as the impurities can be pptd too. (Provided one has access to things like BaCl2.)
fire stilzchen: If you cannot get the Ca(NO3)2 in Germany it can be had in the "czech land" too but the largest bags I've seen are 3 kg. Sometimes it has small stones in it, but nothing dramatic. Upon dissolving it forms some sludge but the Rx makes a lot more (CaSO4) so filtration is necessary anyway.
NH4NO3 solubility data (haven't tried!):
Mass of solute per 1000g solvent H2O
0°C 1173,9
10°C 1506,3
20°C 1898,6
30°C 2367,0
40°C 2891,0
50°C 3484,3
60°C 4208,3
70°C 5024,1
80°C 6042,3
90°C 7474,6
100°C 9309,3
Source: Söhnel, O., and Novotny, P., Densities of Aqueous Solutions of Inorganic Substances, Elsevier, Amsterdam, 1985.
Therefore I think you must be mistaken as the values given look rather like "mass of solute/100g of solvent". The other figures for KNO3 etc. also are very low for the litre!
The reason why I am giving so many numbers is that the soly curve is quite nonlinear and I wouldn't interpolate it from 0° and 100°.
Nitromethane can be bought here as an additive for model plane racing fuel but the price is prohibitive. I believe 25$/1l.

"Azotan" is a Polish term not Czech and it means "nitrate".
Czech for nitrate is "dusicnan", fertilizer grade is "ledek".
Hope that helps.



fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 06-02-2001 03:52 PM
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shit i've made a BIG mistake the solubilities i have post was not for 1 litre it was for 100g h2o2 -> 100ml. sorry
i changed my old message that it is 100ml h2o not 1litre
lagan: thanx, and in czech rep. they have sold me polish fertiliser. but it was really cheap.

- fire stilzchen -



fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 06-03-2001 02:23 PM
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http://people.freenet.de/stilzchen/fertiliser.html my AN bag
PHILOU: must i calculate the reaction again, or can i multiply it with 10 because 1 litre = 10*100ml ?
- fire stilzchen -



Lagen
Frequent Poster
Posts: 174
From:
Registered: MAY 2001
posted 06-04-2001 02:14 PM
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fire stilzchen:
Here are the solubility data you should use (mol/l: KNO3,NH4Cl,KCl,NH4NO3):
0°C 1.348756344 5.558921824 3.726200527 14.66594943
10°C 2.112615115 6.271500461 4.145777629 18.81810257
20°C 3.157774308 7.009535016 4.564699447 23.71900464
30°C 4.506325175 7.781279832 4.971281875 29.57148477
40°C 6.218044992 8.580888868 5.370338354 36.11851994
50°C 8.324368498 9.417612589 5.759657440 43.53017477
60°C 10.80133742 10.28481814 6.139769386 52.57561811
70°C 13.65883409 11.19766719 6.505633526 62.76712227
80°C 16.84122786 12.15461639 6.867035458 75.48717948
90°C 20.35645916 13.16942994 7.219552903 93.38149724
100°C 23.98199637 14.24167129 7.561557290 116.3028269
Okay I will make one daring statement here: The coprecipitation of KCl cannot it be reduced? Because KCl is the least soluble until some point above 30°C. To calculate that point:
Tx=30°C+10x; x*1,711719817+4,506325175=x*0,399056479+4,97128187 5
x*1,312663338=0,4649567; x = 0,3542086; Tx = 33,542°C
KNO3;Tx => 5,112631129 M; KCl => 381,15176 g/l
So I think it's sufficient to add cca 380g KCl to the NH4NO3 solution per 1000g H2O then heat it to 40-50°C to be safe and it should all dissolve. Then as PHILOU said cool to 0°C:
Ks(KNO3;0°C)=(1,348756344)exp2=1,819144[(mol)exp2/(l)exp2]
For example: Using 1000ml water, 500g NH4NO3 (some excess included) follow PHILOU's procedure and add 380g KCl. After dissolving it and cooling to 0°C, following the rule of common ion we have:
[K+],[NO3-]:
initial=5.112631129;6.2466080918
equilibrium=x;1.1339769628+x
x*(1.1339769628+x)=Ks(KNO3,0°C)=1.819144
1.1339769628x+(x)exp2=1.819144; (x)exp2+1.1339769628x-1.819144=0; D=8.562479752
x1,2=(-1.1339769628 +- 2.9261715)/2; x1=0.8960973
4.216533829 moles or 426.305 g KNO3 precipitate.
But! You also loose the excess NH4NO3 in the residual solution and the overall efficiency is only 426.305/516.90357)*409.23258/500=67.5% To find out if it can be improved: If we put c for [KNO3] and y for the "molar excess" of NH4NO3 then moles of precipitate x=(sqrt(y^2+4Ks)-y)/2 and overall efficiency of conversion n=[c/(c+y)]*[c-x]/c=(c-x)/(c+y). Now what excess of NH4NO3 to put in to acheive maximum efficiency?
n'=0 <=> [two pages of deriving snipped]
No sensible extreme of n found! (except for y=0) That means: adding too much excess of NH4NO3 is inefficient! The more you add the more you will waste! Maximum efficiency 73.6% is achieved at minimal excess NH4NO3 (at 409g), in other words not using the common ion effect. You should use it if you wanted to recycle the NH4NO3 from your residual solution but that will contain impurities (chances are it will be sulfates which would be hard to remove by recrystallization), to calculate with those impurities the calculations would be WAY more complicated and practically you would get unpredictable results. I remember I tried it once and it was really too much work separating the KNO3 so I prefer the Ca(NO3)2+K2SO4 method.



fire stilzchen
New Member
Posts: 10
From: de
Registered: MAY 2001
posted 06-07-2001 02:31 PM
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thanks that was very helpfull.
yesterday i tryed this procedure an it worked.
i used 2kg NH4NO3 & 4000ml H2O & 1,5kg KCl and i was filtering about 1,7 kg KNO3 but it's not that quality. i think it's cheaper to buy it because thats a hard work.
- fire stilzchen -



Lagen
Frequent Poster
Posts: 174
From:
Registered: MAY 2001
posted 06-07-2001 08:06 PM
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Congrats!
As to the poor quality... this S..T always happens when using this reaction, it's kinda unpredictable (see the "potassium nitrate from ammonium nitrate" topic in this section), you'd have to recrystallize it or otherwise clean it, but I can't suggest a procedure without knowing the properties of your materials (for example, 1% CaSO4 is harder to remove than 20% Ca(NO3)2). Your NH4NO3 is probably pretty clean, but KCl fertilizer usually holds 10-15% impurities of the hard to remove kind.

Yep it's always better to buy it if you can, without showing your ID... :-(



PHILOU Zrealone
Frequent Poster
Posts: 479
From: Brussels,Belgium,Europe
Registered: SEP 2000
posted 06-08-2001 08:06 AM
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Yes multiply by ten to get mol/l conc
If you play with 100ml batches, then, you would get 67.5g/100ml!Playing with 1000ml would lead you to 67.5g/100ml+67.5g/100ml+...+67.5g/100ml --> 675g/l