french article on nitroethane lab production - translators ?

PSY420 · Fri Jul 01, 2005 7:18 am

As far as I know this specific article never circulated much so I think it still contains highly interesting stuff, even if the general idea of making nitroethane from potassium (sodium) ethylsulfate is not new - the directions for preparing the NaEtSO4 from oleum are what I'm really after. Now, please don't think the use of oleum makes this all impractical. Oleum is easily made by dissolving Na2S2O7 in H2SO4 - the Na2S2O7 in turn is made by heating NaHSO4 or Na2S2O8 (very clean process).

Obviously everybody who's capable of the french language is invited to turn this encrypted article into something the world can read.

Mem. Poudres, 34; 49 - 53 (1952)

Préparation du sulfate mixte d'éthyle et de sodium

Estérification. - Dans un ballon Pyrex de 3 l à 2 tubulures, avec thermomètre,ampoule à brome et agitateur mecanique, on introduit:

369 g (465 cm³), soit 8 mol d'ethanol.

On coule, en agitant et en refroidissant à l'eau glacée :

374 g (194 cm³), soit 4 mol, d'oleum à 20%
Durée de coulée : 30 minutes. Température <= 30°.

Dès que la coulée est terminée, on porte à 45° C et maintient 30 minutes à cette température. On ramène ensuite à 15-20°C. Une prise d'essai donne alors, par titrage de l'acidité libre, le coefficient de transformation de SO4H2 et le poids de carbonate de sodium nécessaire à la neutralisation.

Neutralisation

Le produit de la réaction est versé dans une ampoule à brome. On me dans le ballon à réaction:

- 500 cm³ d'H2O;

puis on introduit en agitant :
- 274 g de CO3Na2 à 94% en poudre finement divisée.

On coule alors le liquide réactionnel contenu dans l'ampoule à brome, en agitant
vivement. Température de réaction <= 40°C.

La réaction est faiblement exothermique. On lamaintient dans les limites de tem-
pérature par refroidissement intermittent à l'eau courante. La neutralisation es vérifiée par des touches au papier de tournesol et complétée au besoin, jusqu'à faible alcalinité, par quelques centimètres cubes de lessive de soude à 30%.

Le contenu du ballon est versé dans un bécher de 1,5 l, cristallisé à 0°C puis filtré sur verre fritte n° 3 et lavé avec 40 cm³ d'eau glacée. Le sulfate de sodium reste sur le filtre où il retient environ 6% de l'éthylsulfate de sodium obtenu. Volume du SO3Na2, 10 H2O sec = 200g environ. La solution filtrée est introduite dans un ballon de 2 l, surmonté d'une colonne à 12 plateauc. On rectifie jusqu'à ce que la température atteigne 100° au sommet de la colonne. Ethanol pur rectifié : 220,5 g comptés en alcool absolu.

Le liquide résiduel est ensuite concentré sous vide, de manière à reduire son volume à 530 cm³ environ. La composition de cette solution, de densité 1,36 est
la suivante :

Sulfate double d'ethyle et de sodium : 56%
Sulfate de sodium : 0,38%
Bicarbonate de sodium : 0,26%
Cette solution est utilisée telle quelle pour la réaction avec le nitrite de soude.

Bilan de l'operation:

Ethanol introduit : 8 moles;
Ethanol récupéré : 4,8 moles;
Ethanol disparu : 3,2 moles;
Acide sulfurique mis en jeu : 4 moles;
Ethylsulfate obtenu : 2,72 moles;
Rendement sur l'acide sulfurique : 68%
Rendement sur l'ethanol disparu : 85%

2 Réaction du nitrite de sodium sur l'ethylsulfate de sodium

Appareillage

L'appareillage est le même que celui qui a été décrit pour la préparation du nitrométhane à partir du méthylsulfate de soude.

Mode Opératoire

On introdui dans le ballon à réaction :

137g d'eau;
26,5g (0,0625 x 3 moles) de carbonate neutre de potassium technique à 98%.
On agite pour assurer la dissolution, puis on ajoute :
320 g(4,5 moles) de nitrite de sodium technique à 97%;
6 ml d'alcool oléique, ou d'alcool cétyl-oléique (antimousses)

Volume chargé = 420 mL environ.

On chauffe à 130°C, au bain de glycérine, en agitant. Dans l'ampoule à brome, on place une quantité de solution de sulfate mixte d'ethyle et de sodium contenant 444 g (3 moles); Volume approximatif : 750 mL. Durée de coulée 50 à 60 minutes. La vitesse de coulée est réglée de telle sorte que la température de la masse en réaction reste comprise dans les limites indiquées : 125 à 130°C.

Il est nécessaire d'agiter énergiquement pour assurer une bonne dispersion des sels qui cristallisent (sulfate de sodium) es aussi pour briser les mousses assez abondantes qui envahissent le réacteur pendant 30 minutes environ.

la distillation du nitroéthane commence dès la coulée des premiéres gouttes de la solution d'ethylsulfate et la température des vapeurs à la sortie du ballon est voisine de 100°C. La coulée de la solution d'ethylsulfate terminée, on introduit 100 mL d'eau pour achever l'entraînement du nitroéthane formé. Durée de coulée : 10 minutes environ. La réaction s'accompagne d'un dégagement de gaz non condensables à - 80°C.

Separation et purification du nitroéthane

La distillat recueilli dans le condenseur est séparé en deux couches. On le distille,sans séparation préalable des deux couches, à pression atmosphérique dans un ballon de 1 L à col rodé surmonte d'une colonne à 12 plateaux en verre Pyrex (diameter 25 mm, H utile = 40 mm).

La distillation commencee vers 30°C. La fraction de 2 à 3 g qui passe avant 74°C est éliminée. Elle marque ensuite un palier à 87°C. On arrête la distillation quand la température atteint 99,8°C. Le distillat est séparé en deux couches :

1° Couche inférieure (C2H5NO2 saturé d'eau et d'ethanol) = 104 g
Titre = 91,6 g soit 88,2% de C2H5NO2.

2° Couche supérieure (eau et éthanol saturés de C2H5NO2) = 96,1 g.
Titre = 4,39 g soit 4,56 % de C2H5NO2,
La rectification de la couche inférieure donne du nitroéthane pur et anhydre.

Bilan de la réaction
Éthylsulfate mis en jeu : 444 g (3 moles).
Nitroéthane obtenu : 96 g (1,28 moles).

Rendement en pourcentage de la théorie :

- sur éthylsulfate de sodium : 42,6 %
- sur ethanol disparu : 42,6 x 0,85 = 36,2 %
- sur acide sulfurique : 42,6 x 0,68 = 29%

[... skipped : Et2SO4 + NaNO2]

fin

--PSY420--

2spun · The Resistor

.Mem. Powders, 34; 49 - 53 (1952)

Preparation of mixed sodium and ethyl sulphate

Esterification. - Into a balloon Pyrex of 3 L with 2 pipes, with thermometer, bulb with bromine and agitator mecanic, one introduces:

369 G (465 cm³), are 8 mol of ethanol.

One runs, while agitating and while cooling with frozen water:

374 G (194 cm³), are 4 mol, of oleum with 20%
Duration of cast: 30 minutes. Temperature < = 30°.

As soon as casting is finished, one carries to 45° C and maintains 30 minutes at this temperature. One brings back then to 15-20°C. A test specimen gives then, by titration of free acidity, the SO4H2 conversion rate and the sodium carbonate weight necessary to neutralization.

Neutralization

The product of the reaction is versed in a bulb with bromine. One me in the balloon with reaction:

- 500 cm³ of H2O;

then one introduces while agitating:
- 274 G of CO3Na2 with finely divided powder 94%.

One then runs the reactional liquid contained in the bulb with bromine, while agitating
highly. Temperature of reaction < = 40°C.

The reaction is slightly exothermic. One lamaintient within the limits of tem-
pérature by intermittent cooling with running water. Neutralization be checked by keys with the litmus paper and are supplemented if need be, until low alkalinity, by a few cubic centimeters of soda detergent with 30%.

The contents of the balloon are versed in a bécher of 1,5 L, crystallized with 0°C then filtered on glass n° 3 and washed with 40 sinters frozen water cm³. The sodium sulphate remains on the filter where it retains approximately 6% of the sodium éthylsulfate obtained. Volume of SO3Na2, 10 dry H2O = 200g approximately. The filtered solution is introduced into a balloon of 2 L, surmounted of a column with 12 plateauc. One rectifies until the temperature reaches 100° at the top of the column. Rectified pure ethanol: 220,5 G counted out of pure alcohol.

The residual liquid is then concentrated vacuum, so as to approximately reduce its volume to 530 cm³. The composition of this solution, of density 1,36 is
the following one:

Sulphate doubles ethyle and of sodium: 56%
Sulphate sodium: 0,38%
Sodium bicarbonate: 0,26%
This solution is used just as it is for the reaction with soda nitrite.

Assessment of the operation:

Introduced ethanol: 8 moles;
Recovered ethanol: 4,8 moles;
Disappeared ethanol: 3,2 moles;
Acid sulphuric brought into play: 4 moles;
Ethylsulfate obtained: 2,72 moles;
Output on the sulphuric acid: 68%
Output on the disappeared ethanol: 85%

2 Reaction of sodium nitrite on the sodium ethylsulfate

Equipment

Equipment is the same one as that which was described for the preparation of nitromethane starting from the soda méthylsulfate.

Procedure

One introdui in the balloon with reaction:

water 137g;
26,5g (0,0625 X 3 moles) of neutral technical potassium carbonate with 98%.
One agitates to ensure dissolution, then one adds:
320 g(4,5 moles) of technical sodium nitrite with 97%;
6 ml of oleic alcohol, or cétyl-oleic alcohol (antifoaming)

Volume charged = approximately 420 ml.

One heats with 130°C, with the glycerin bath, while agitating. In the bulb with bromine, one places a quantity of mixed sulphate solution of ethyle and sodium containing 444 G (3 moles); Approximate volume: 750 ml. Duration of casting 50 to 60 minutes. The speed of casting is regulated so that the temperature of the mass in reaction remains included/understood within the limits indicated: 125 with 130°C.

It is necessary to agitate vigorously to ensure a good dispersion of salts which crystallize (sodium sulphate) are also to break the rather abundant ship's boys which invade the engine during approximately 30 minutes.

the distillation of nitroethane starts as of the casting of the premiéres drops of the solution of ethylsulfate and the temperature of the vapors at the exit of the balloon is close to 100°C. The casting of the solution of ethylsulfate finished, one introduces 100 ml of water to complete the drive of formed nitroethane. Duration of cast: approximately 10 minutes. The reaction is accompanied by a non condensable gas outburst with - 80°C.

Separation and purification of nitroethane

The distillate collected in the condenser is separate in two layers. It is distilled, without preliminary separation of the two layers, with atmospheric pressure in a balloon of 1 L with ground collar surmounts by a column with 12 plates out of glass Pyrex (diameter 25 mm, H useful = 40 mm).

Distillation commencee towards 30°C. The fraction from 2 to 3 G which pass before 74°C is eliminated. It marks then a stage with 87°C. One stops distillation when the temperature reached 99,8°C. The distillate is separate in two layers:

1° lower Couche (C2H5NO2 saturated with water and ethanol) = 104 G
Titrate = 91,6 G is 88,2% of C2H5NO2.

2° higher Couche (water and ethanol saturated with C2H5NO2) = 96,1 G.
Titrate = 4,39 G is 4,56 % of C2H5NO2,
The correction of the sub-base gives pure and anhydrous nitroethane.

Assessment of the reaction
Éthylsulfate brought into play: 444 G (3 moles).
Nitroethane obtained: 96 G (1,28 moles).

Output expressed as a percentage of the theory:

- on sodium éthylsulfate: 42,6 %
- on ethanol disappeared: 42,6 X 0,85 = 36,2 %
- on sulphuric acid: 42,6 X 0,68 = 29%

[... skipped: Et2SO4 + NacNo2 ]

end

hahas · Fri Jul 01, 2005 11:02 am

there is a nitroethane thread at WD containing that article, and also the nitromethane article, posted by Lugh. there was later posted by someone else an ok translation of it, considering that it was computer-generated, and this is that translation. the Na ethyl sulfate discussion in the thread focused on the use ordinary H2SO4, though. until someone comes up with something more correct:

http://rapidshare.de/files/2719217/translation.doc.html

PSY420 · Fri Jul 01, 2005 2:43 pm

Ah, great. Thx a lot !

IMHO the preparation of NaEtSO4 w/ H2SO4 sucks (I still have got to get some articles from the library though). Since preparation of oleum looks so easy I don't understand why people refrain from thinking about using it.

The cleanest way of obtaining NaEtSO4 would probably be neutralizing the HEtSO4 that's produced when SO3 is distilled into cold EtOH, as done in DE133542 but SO3 vapours are not a very tame toy to play with.

Here's another nice example of how oleum could be put to use:

DE77278

Under icebath-cooling 90 g amyl alcohol are mixed with 100 g conc. H2SO4 in a stirring vessel and 100g 80% oleum (or an equivalent amount of weaker oleum) are added with constant cooling, so that no rise in temperature occurs. Then the mix is left standing for 12 h while cooling with water. No decomposition occurs thereby. The reaction mixture is poured on ice and water added; a clear, nearly colorless solution is obtained. This is neutralized in the cold with Ca(OH)2 or CaCO3, filtered, the filtrate converted into the sodium salt with Na2CO3 and the solution evaporated to dryness in vacuo. This is required to get an absolutely clean product and a complete yield (200 g Na amyl sulfate - near theoretical yield)

It is also possible, without changing the result essentially, to add a weaker grade oleum directly to the ice cooled alcohol, for example 400 g 20% oleum. If amyl alcohol is exchanged for its homologes, like methanol, in the above example the homologous salts of the sulfuric acid esters are obtained in the same manner.

--PSY420--

loki · guinea pig

isn't oleum 100% sulphuric acid

joe_aldehyde · huxleys associate

no, loki. it is fuming sulfuric acid of which about 37% are present as bisulfuric acid, H2S2O7. sometimes also expressed as SO3 dissolved in H2SO4.

loki · guinea pig

ah ok, well 100% is the threshold for forming oleum then i guess. water turns oleum into sulphuric acid

PSY420 · Fri Jul 01, 2005 6:34 pm

I think this thread covers most questions about oleum quite nicely :

https://www.synthetikal.com/hiveboard/chemistrydiscourse/000516819.html

--PSY420--