Topic: hydroxylamine ref. (Read 258 times)
twodogs
(Stranger)
10-17-02 03:16
No 369562
200 gms nitromethane, 300 gms 28% HCl and 300 gms Glacial Acetic Acid were mixed and slowly heated to just below reflux and temp held there for about 4 hours then temp adjusted for relux and left for 12 hours. Left to cool for 8 hours. Crystals formed. Liquid was decanted and reduced to about 200 mls and put in freezer overnight. More crystals were recovered. Total yield 100 gms. Crystals became yellowish on standing.
Tricky
(Stunning)
10-17-02 03:43
No 369566
I think it's gibberish.
It's impossible.
karl
(Hive Bee)
10-17-02 04:01
No 369572
Nitromethane has a nitrogen in the fifth oxidation state while hydroxylamine in the third. How is the nitromethane being reduced by GAA. I doubt the acetic acid could be so readily oxidised.
moo
(Hive Bee)
10-17-02 04:49
No 369578
Please read Post 263772 (halfapint: "Re: Nitrostyrene or Nitropropene electrochem reduction", Chemistry Discourse) and Post 285259 (uemura: "Oldie, but Goodie", Novel Discourse).
twodogs
(Stranger)
10-18-02 04:11
No 369911
Say what??
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To 200 mL of methanol were added 30 grams of nitromethane and 60 grams of oxalic acid. The resulting mixture was stirred to form a solution. The solution was then refluxed at atmospheric pressure at a temperature ranging from 60 to 70C (refluxing), for 20 hours. Hydroxylamine and formic acid were obtained.
United States Patent 3,380,807
Work up: crash out hydroxylamine sulfate with H2SO4, assuming the solution is not to wet. Or baseify and vacuum distill out the hydroxylamine freebase then add H2SO4 and distill your formic.
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Patent US3380807
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German Patent DE 1247284
Abstract
Hydroxylammonium chloride has been used heretofore for making H2NOH because of its soly. The cheaper hydroxylammonium sulfate (I) is suitable for the manuf. of H2NOH by making a fine suspension of I in an alc. contg. (shows a less than or equal to sign) 3 C and treating with NH3. The insol. I that remains and the (NH4)2SO4 formed in the reaction mix are readily sepd. Thus, finely ground I 246 g. is suspended with stirring in a mixt. of MeOH 250 and PrOH 250 ml. and NH3 is introduced at a rate of 20 l./hr.; the temp. rises from .apprx.20° to 45° and after .apprx.3 hrs. the reaction ceases as can be noted by the escape of NH3. An addnl. 20 g. of I is added and the mixt. is stirred for another hr. After cooling, the excess I and (NH4)2SO4 are filtered off to provide a soln. of H2NOH 95.7 g., corresponding to a yield of 89.2%.
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US Patent 3386803
Abstract
H2NOH and aldehydes are produced by the reaction of a water-sol. alkali metal salt of a primary nitroparaffin with HCO2H or oxalic acid, optionally in the presence of an inert solvent. Thus, a soln. of 10 g. PrNO2 and 4 g. NaOH in 100 ml. water was added slowly to 50 ml. HCO2H and the mixt. stirred 90 min. and combined with aq. HCl to give EtCHO and 51% H2NOH.HCl. A soln of 10 g. PrNO2 and 4 g. NaOH in 100 ml. water was added slowly to 25 g. oxalic acid in 200 ml. MeOH and the mixt. treated as above to give EtCHO and H2NOH. Similar treatment of EtNO2 and BuNO2 gave the corresponding aldehydes and H2NOH.
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Preparation of high-purity hydroxylamine sulfate from an impure solution.
RO 95695
Patent written in Romanian.
Abstract
An impure dil. soln. contg. hydroxylamine sulfate is treated with acetone or MEK at pH 6-7 and 50-100°, the oxime formed is extd. with CCl4, C2H4Cl2, or C2H2Cl4 and then hydrolyzed by boiling with 5-15% H2SO4 or HCl soln. High-purity (e.g., 98%) hydroxylamine sulfate is isolated by known methods (e.g., crystn.).
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Patent US2749217 column 1 lines 50+ mentions making hydroxylamine from nitromethane using H2SO4.
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Ueber eine Verbindung von Nickelsulfat mit Hydroxylamin
Rudolf Uhlenhuth
Ann. Chem. 307, 332-334 (1899)
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Action of Mineral Acids on Primary Nitroparaffins
S. B. Lippincott & H. B. Hass
Industrial & Engineering Chemistry 31, 118-120 (1939)
Abstract
Convenient and economical procedures have been developed for the preparation of acetic, propionic, butyric, and isobutyric acids in good yields from the corresponding primary nitroparaffins by refluxing them with 85 per cent sulfuric acid. Hydroxylamine acid sulfate is a by-product of the reaction. Propionohydroxamic acid has been prepared from 1-nitropropane and concentrated sulfuric acid in fair yield.
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Hope this helps. I've got more for this topic in a day or two.
US3380807.pdf
(111.8 kB - downloaded 35 times.)
Electrolysis of nitric acid
For some reason, I discovered this document on the electrolysis of nitric acid, which I never noticed before. I hope noone else posted it somewhere, I don't even know how I obtained it.
Anyway - it's actually quite interesting, and confirms hodges observation - the electrolysis of HNO3 causes reduction of the nitrogen, not oxidation. That is, it depends on the cathodes being used, Pt electrodes and a diaphragm produce nitric oxide, copper cathodes ammonia, and polished zinc 46 % hydroxylamine (next to ammonia!!)
So essentially, without electrode separation, the electrolysis of HNO3 with Zn cathode should produce ammonium nitrate and hydroxylamine nitrate!
I thought this is too interesting to leave this unmentioned.
Attachment is as .doc, & large, might change this later. But have a look for now
.HYDROXYAMINE
In 1902 it was shown by J. Tafel that nitric acid canbe reduced in a divided cell, in the presence of sulphuricacid, in such a manner as to give a good yield of hydroxy-lamine sulphate, and the process was covered by patentsissued about that time.Tafell showed that a mercury cathode or one of amal-gamated lead gives the best results. At a platinum cathode very little reduction takes place, and the products are ammonia and hydroxylamine. According to Tafel, a lead cathode gives a 40 per cent, conversion of nitric acid to hydroxylamine, but with a copper electrode only 15 per cent reduction to this substance takes place, whilst much ammonia is formed. Since hydroxylamine is not reduced to ammonia by acopper cathode, it follows that the reduction of nitric acid
to this gas is direct, and depends upon the specific action of the metal. For the preparation of hydroxylamine, dilutenitric acid may be used, but the strength of the sulphuricacid into which the nitric acid is dropped or slowly run,should not be less than 40 per cent.Tafel showed that the sulphate is comparatively stablein the presence of sulphuric acid even at a temperature of40° C. He obtained the hydrochloride by using hydro-chloric acid in place of sulphuric acid, and a cathode ofspongy tin gave satisfactory results. The reduction maybe represented by the equation :—
HN03 + 3H2 = NH20H + 2H2O.
According to the patents of Boehringer and Sohne,
1:atwo-compartment cell is employed containing 50 per cent,sulphuric acid in each compartment. The cathode is ofamalgamated lead, whilst the anode is lead. A 50 percent, nitric acid solution is dropped into the cathode com-partment during the passage of the current, and the tem-perature kept below 20° by cooling coils. The currentdensity employed is 60-120 amps, per dm.2
According to a French patent,
2:an anode of platinumis used with a tin cathode. Sodium nitrate solution isdropped into the cathode compartment, and the anolyte issodium chloride solution. The yield of hydroxylamine issaid to be 60-80 per cent, and chlorine is a by-product.A suitable arrangement for producing hydrochlorideon a large scale is described by E. H. Pritchett.
cathode compartment is filled with three volumes of waterand one volume of hydrochloric acid (density—1*20).
The anode liquid is cooled by causing it to circulate through alead pipe immersed in a freezing mixture, which latter isused to cool the cathode liquor. The current density used is 50 amps, per dm 2 at 25 volts, and the nitric acid (density 1*4) mixed with one volume of water is run into the cathode compartment at the rate of 30 c.c. per hour. The reduced liquor on being evaporated in vacuo gives 80 per cent, of the calculated amount of hydroxylamine hydrochloride.
3104731-The-Manufacture-Of-Chemicals-By-Electrolysis.pdf
(824.73 kB - downloaded 20 times.)
@Vanadium-the sulfate salt works almost exactly like the hydrochloride of hydroxylamine for almost everything, especially oxime formation.
Only difference in my notes is solubility and molarity.
@Vanadium-the sulfate salt works almost exactly like the hydrochloride of hydroxylamine for almost everything, especially oxime formation.
Only difference in my notes is solubility and molarity.
Derivative Type: Hydrochloride
CAS Registry Number: 5470-11-1
Additional Names: Oxammonium hydrochloride
Molecular Formula: H3NO.HCl
Molecular Weight: 69.49.
Percent Composition: H 5.80%, N 20.16%, O 23.02%, Cl 51.02%
Properties: Monoclinic columnar crystals; slowly dec when moist. d17 1.67. mp about 151°. One gram dissolves in about 1 ml water (83 g in 100 ml water at 17°); 19 ml alcohol; 8 ml methanol. Sol in glycerol, propylene glycol. Insol in cold ether. pH of 0.2 molar aq soln 3.2. Keep well closed. LD50 orally in mice: 408 mg/kg (Riemann).
Melting point: mp about 151°
Density: d17 1.67
Toxicity data: LD50 orally in mice: 408 mg/kg (Riemann)
Derivative Type: Sulfate
CAS Registry Number: 10039-54-0
Additional Names: Oxammonium sulfate
Molecular Formula: (H3NO)2.H2SO4
Molecular Weight: 164.14.
Percent Composition: H 4.91%, N 17.07%, O 58.48%, S 19.54%
Properties: Crystals, mp about 170°. Freely sol in water.
Melting point: mp about 170°
