[Marius]

Dintr-o discutie mai veche despre combustibili mai performanti disponibili in Romania cineva imi sugera mingile de tenis ca sursa de nitroceluloza pt motoare racheta.
RL10 mi-a zis ca pot extrage comforul si stabilizatorii din mingi folosind diluantul si alcoolul ca sa purific dinitroceluloza de stabilizatori si alte adaosuri
Mingi de ping pong sparte am adunate o gramada si vreau sa ma apuc experimente sa vad daca reusesc sa fac un combustibil util din ele
Pana acuma ce am reusit a fost sa le fac ca o pasta adaugand acetona apoi am adaugat pulbere neagra fara sulf facuta de mine si le-am uscat sub forma de batoane care aveau o viteza de ardere bunicica dar nu energica adica am micsorat viteza pulberi fara sulf care este ca flash powder si am marit viteza de ardere a mingilor de tenis
Daca ati reusit sa realizati ceva cu mingi de tenis sau aveti ceva sugestii care mi-ar fi de ajutor spuneti-mi si mie

[Marius]

Vad ca nu ma ajuta nimeni in problema asta in afara de RL10
Am intrebat acelasi lucru si in alte locuri iar raspunsul primit a fost sa utilizez mingile in amestecuri cu oxidanti " A mix of ping pong ball, KNO3, NH4NO3 & ammonium dichromate is better as far as power, is cheaper" sau ca ar fi mult mai simplu sa obtin celuloza hexanitrat pe care sa o amestec cu acetona si sa o presez in forma
O sa fac incercari si cand obtin ceva puternic ieftin si sigur o sa postez

[bitex]

Oricat ar fi de mare rezerva, o arzi in 2 secunde pe toata.
Daca te mananca pasiunea, obtine nitroceluloza corect, fara sa o scoti din tot felul de deseuri, ca poti.
Arde repede, vezi daca o poti folosi in motoarele de amator. E mult de experimentat, nu cred ca gasesti usor informatii. Daca era ceva fiabil pentru nivelul nostru de activitate poti banui ca asta foloseam cu totii. Nu se stie niciodata de unde apare o reteta de combustibil stabil. Baga mare!
Spor la treaba!

[Marius]

Am fost dezamagit de nitroceluloza din mingi de ping pong, poate nu am folosit eu cei mai buni reactivi la extragerea comforului dar produsul obtinut la viteza de ardere nu diferea cu mult de cea de la care am pornit iar randamentul separarii a fost ochiometric vorbind cam 50% deci clar nu se merita.
Singurul lucru bun care se poate face cu mingile de tenis este folosirea lor pe post de liant in motoare
Ceea ce o sa fac este sa folosesc urmatoarea reactie de obtinere a nitrocelulozei:

*Safety*
This synthesis uses concentrated acid which can cause severe burns and blindness. It also produces some fumes. Mainly NO2 and some H2SO4 mist. These fumes will really hurt you and can kill you. Do not run this reaction indoors unless it is in a fume-hood, and make sure it's a windy day or use a fan for ventilation outside.

What you'll need:

Equipment:
1.) glass beaker at least 250ml
2.) glass stir rod
3.) non-open flame heat source
4.) Large glass bowl or beaker at least 500ml

Chemicals:
1.) 55ml 98% sulfuric acid
2.) 32grams of KNO3, NaNO3, or NH4NO3
3.) about 50grams of sodium bicarbonate
4.) 5grams of cotton balls (100% pure cotton)
5.) a couple liters of fresh (preferably distilled) water and some ice.

Procedure:

1.) Prepare your materials;

Sulfuric acid
- Assure that your H2SO4 is concentrated as much as it can be by heating it to >110C or until white fumes are emitted. Allow the sulfuric acid to cool to room temperature before proceeding

Nitrate salt
- Ammonium nitrate is the best nitrate salt to use because of its higher solubility, but the others (KNO3, NaNO3) will work fine. Make sure the nitrate salt of choice is dry and thoroughly sifted of all clumps. Weigh it accurately to 32 grams.

Cotton balls
- Take 5 grams of cotton balls (about 5 balls) and carefully unroll them into long thin sheets of cotton. Try and separate any clumps or knots in the fibers.

Bicarb wash
- Make a saturated solution of sodium bicarbonate (baking soda). At least 500ml or more.

2.) Preparation of the nitrating bath;

Begin adding you nitrate salt to the 55ml of room temperature sulfuric acid. Add the nitrate salt in 5grams increments and insure that it is fully dissolved after each addition by stirring with the glass stir rod. If you are using KNO3 you will have some trouble getting the last few additions of the salt to dissolve. This can be solved by gently heating the acid to about 75-80C by placing the beaker with the acid in it into a boiling water bath during the additions of the KNO3. After all the nitrate salt has been dissolved allow the acid/nitrate mix to cool to room temperature.

3.) Nitration of the cotton.

Add your cotton sheets, one at a time to the acid/nitrate salt mix. Using the stir rod, make sure that each piece gets thoroughly saturated and submerged in the nitration bath. Once all of the cotton is added, let the mix nitrate for no less than 12 hours. Using your glass stir rod, mix up and turn the cotton in the acid about every 2 hours.

4.) Rinsing and neutralization.

After 12 hours use you glass stir rod to press any acid out of the cotton and pour off the excess acid. You should now have a clump of acid soaked cellulose nitrate in your beaker. Add ~200ml of ice water to the beaker and swirl around. Then carefully pour off the water and leave the cotton behind. Repeat this rinse several time using cold water. The goal is to get as much of the acid off of the cotton as possible, so stir and press it with the stir rod while it's under the cold water. After several water rinses, place the nitrated cotton into the baking soda solution (Sodium Bicarbonate). It will bubble as any remaining acid is neutralized. Stir and separate the cotton in the baking soda water for several hours to assure all the acid is neutralized. Now drain the bicarbonate solution and thoroughly wash the cotton in hot water to remove any excess sodium bicarbonate. Spread out your cotton in a cool, dry place and let it dry thoroughly. It may take several days to really dry.

This cellulose nitrate will burn very fast, but if you want to assure that you have cellulose in its highest nitration state (hexanitrate) Just take the dry and ready cellulose nitrate and repeat the nitration procedure on it again with a fresh nitrating bath, as if it were just cotton. This will produce the best cellulose nitrate, it will rival the cellulose hexanitrate made with HNO3 and H2SO4, albeit it's a lot slower and more work .

To make a gel, just drip some dry acetone onto the cellulose nitrate. Just enough to make a thick, clear gel. This can be pour casted into a rocket engine and allowed to dry for several days to a week. It can then be cored and fused if needed, depending on your rocket design

Vata se nitreaza in 2 etape a cate 12 ore intre care vata este spalata, stoarsa, si introdusa in amestec de nitrare Acuma ce-o iesi va spun peste cateva zile numai sa gasesc pana atuncea o metoda sigura si precisa de testat combustibilul obtinut