heksogen
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gelati in hydrazine synthesis
what is the role of gelatin in hydrazine synthesis???
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S.C. Wack
bibliomaster
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Rachig hydrazine
The glue, gelatin, etc. tie up trace metal ions. Even the smallest amounts of copper will otherwise kill the reaction. The metal catalyzes the bad
reaction: 2NH2Cl + N2H4 = 2NH4Cl + N2.
Absolutely pure reagents and water will give great yield of hydrazine without inhibitors.
[Edited on 10-5-2004 by S.C. Wack]
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chemoleo
Biochemicus Energeticus
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Please do search before you post. Hydrazine has been discussed in at least three BIG threads, and all the info is there!
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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heksogen
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mega's synth
I' ve got Megalomania procedure of making hydrazine.
Synthesis: Prepare a solution of 1500 mL of 28-29% ammonium hydroxide, 900 mL of water, 375 mL of 10% gelatin solution, and 1200 mL of normal sodium
hypochlorite solution. It is absolutely imperative to use distilled water, the presence of any contaminant ions will screw up this reaction! It is
possible to use starch, glue, or glycerol instead of gelatin, but they are inferior. Mix these chemicals in a large glass dish, like a pie plate or
bowl, or just use several portions, as this is nearly a gallon of liquid. This mixture is heated as rapidly as possible and boiled down to one-third
of its original volume. The solution is then cooled thoroughly with ice and suction filtered twice to remove any impurities. When filtering, first use
towels (like a washcloth), then use regular filter paper on top of some cloth (like from a T-shirt).
The resulting liquid is dilute hydrazine hydrate. To make concentrated hydrazine hydrate, mix 144 mL of dilute hydrazine with 230 mL of xylene in a
round-bottomed 500-mL Florence flask. Fractionally distill the mixture in an atmosphere of nitrogen, the xylene will first pass over with most of the
water, then the hydrazine will pass over. Keep the fractions separate of course. The resulting hydrazine hydrate will be 90-95% hydrazine. This
concentration procedure is meant for 60% hydrazine hydrate, since the hydrazine hydrate prepared above may be greater or less than 60%, some
experimentation may be needed to find the proper amount of xylene to use (more xylene is needed for dilute hydrazine, less for more concentrated
hydrazine).
To obtain anhydrous hydrazine, mix 20 g of potassium hydroxide per 100 g of >90% hydrazine hydrate in a beaker, let this mixture stand overnight so
much of the water can be withdrawn. After standing, filter the solution to remove the hydroxide. Add to the filtered liquid an equal amount by weight
of sodium hydroxide. Place this mixture in a round-bottomed 500-mL Florence flask, reflux for 2 hours, then distill in a slow stream of nitrogen. You
must use nitrogen, distillation in air may lead to an explosion!
I think the amounts given are bad - I'll explain below:
reaction:
2 NH3 + NaOCl ----> H2NNH2 + NaCl + H2O
two moles of ammonia react with one mole of NaOCl.
2 moles of NH3 = 34 grams
1 mole of NaOCl = 74.5 grams.
In 1500 ml of 28% NH3 aq there is
0.9 g/ml * 1500ml * 0.28 = 378 grams of pure NH3.
1200ml of normal NaOCl solution contains 1.2mole * 74.5 = 89.4 grams of pure NaOCl. The proportion is:
34:74.5 and 378:89.4
So Megalomania uses nearly 10 times more ammonia than needed. I know that some NH3 will volatize, but not 300grams!!!
So....
What's the proper procedure??
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vulture
Forum Gatekeeper
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UTFSE.
One more crappy thread of yours and you'll lose posting capability for a week.
Closed.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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