I did find that article, but then I saw a few other things that had made it look they maybe they had a clue. hopefully they do.. but if not -- I'll have to consider other options (maybe... northern blotting? :S)

That paper on the nitrite isomerization is interesting, asbestos is now very hard to come by, may be fiberglas can be used instead? Or a finely divided metal in the abscense of hydrogen? Low yields should not be a problem since unreacted ethyl nitrite can be easily separated from nitroethane.

The idea would be: Inside a container with HCl and Ethanol one adds a solution of a nitrite, te resulting gases are dried with a calciul chloride U tube and passed trough a tube furnace heated to 120 ºC by the steam of a pressure cooker, just like a condensor packed with fiberglass or copper metal powder, the exiting gases are passed trough a condensor setted on reflux mode, Nitroethane condenses and drips to a container, ethyl nitrite gas escapes and its returned to the ethyl nitrite generator. Air from all the system must be replaced by an inert gas.

Reducing nitroethane to ethylamine is a sacrilege, may be someone needed ethylamine for something like a weird analog and could make it from ethyl nitrite... but seems like hoffman of propionamide is the best bet.

There are ceramic fibre substitutes for asbestos nowadays,



This is basically what you are talking about ethyl nitrite and paraffin oil are put into the first tube, in the paper they have an upright spiral consenser in between the nitrite/paraffin oil mixture and the combustion tube. They had a 90cm combustion tube (which are usually made from quartz to withstand really high temps, but would not be needed for the 100-130*C needed here), filled with ceramic fibre. The combustion tube is heated to 125*C, the combustion tube actually running through a furnace box with thermometer indicating the temp.

When the combustion tube is up to temperature (the themometer in the furnace says 125*C), heat is applied to the first tube to vaporize the nitrite. (In the paper the flask with the nitrite mix is actually put into the furnace with the combustion chamber but the above diagram (for illustration purposes) we will omit that.) When heat is applied to the nitrite/paraffin oil mix the nitrite vaporizes, and a gentle stream of CO2 is started which carries the vapor into the combustion tube. What comes out of the other end of the combustion tube is mainly nitrite with some nitro compound, the nitro collects in the first empty tube that is immersed in a cold water bath. The nitrite vapor makes it through that first trap easily but gets dissolved into the ice cold methanol.

So no HCl!!! Do the esterification, purify and take a relatively pure, dry nitrite into the reaction above. They specify a DRY stream of carbon dioxide, which should tell you steam cant be used as its about as WET as you can get. The actual setup used would be upright (according to the description in the paper), and the nitrite/paraffin oil, with condenser above, and combustion tube above that would all be put into the furnace. The reaction starts at 100*C and is vigorous at 120*C in fact they found that the best yields were had at around 120-130*C so the temps are not ridiculous.

regarding steam, from the paper;

"In order to study the influence of moisture, the gaseous nitrite was dried by passage through one or two calcium chloride tubes and then passed into the heated tube, when it was found that very little liquid collected in the receiving U-tube and most of the nitrite was passing out unchanged. This phenomenon was observed in the case of all the nitrites. It appears that the presence of moisture, which is always present in the rapidly dried nitrites, facilitates the conversion of the nitrite into the nitro-compound. In order to ascertain if the presence of larger quantities of moisture in the gaseous nitrites gives rise to a larger percentage of nitro-compounds, the nitrites were passed through a wash-bottle containing water before entering the heated tube. It was found that when surcharged with moisture the nitrite dissociated more rapidly, yielding larger quantities of alcohols, aldehydes and acids without any appreciable increase in the yield of the nitro-compound. It appears that in the presence of traces of moisture, two reactions proceed simultaneously, namely, the conversion of the nitrite into nitro-compound and the dissociation of the nitrite; and with the increase in the proportion of water the latter reaction proceeds with greater rapidity."

"the idea was not to use steam to carry the nitrite but to heat the combustion tube"

Ohh yeah, sorry Soma. That is a good idea!

Pressure will not work in this case! The traps wont work ect, you will contaminate the system with vapor from ethanol and HCl. If you are thinking about generating the ethyl nitrite in situ you will need a condenser on the flask the the esterification is taking place in. So a flask with the reactants and a reflux condenser on that, then heat can be applied to vaporize the ethyl nitrite, the water should not make it past the condenser.

Regarding industrial processes;

"EXAMPLE 1

Continuous Process for Making Sodium Azide Using Two Reactors with Recycle

in the Second Reactor
A first reactor is charged with sodium nitrite (106.7 grams, 97% pure, 1.5 moles). ethanol (69 grams, 1.5 moles), and water (150 milliliters). The resulting solution is stirred, and sulfuric acid (73.5 grams, 0.75 mole) mixed with 147 milliliters of water is slowly added. Ethyl nitrite (boiling point=17° C.) was generated from the reaction mixture, and the ethyl nitrite vaporized and exited the reactor through a condenser. The ethyl nitrite is passed via a tube to a second reactor and is fed into the second reactor at a point below the surface of a solution contained therein. The solution in the second reactor is composed of 64% hydrazine (25 grams, 0.5 mole), and sodium hydroxide (20 grams, 0.5 mole) dissolved in ethanol (200 milliliters). As the ethyl nitrite entered the solution contained in the second reactor, a mild exotherm was noted, and the desired sodium azide began to form. Solid sodium azide was continuously removed from the resulting slurry by filtration, and the filtrate was replenished with additional hydrazine solution and solid caustic, and the replenished filtrate was recycled back into the second reactor for contact with fresh ethyl nitrite. Thus, a continuous process was provided for production of sodium azide including recycle of the reactants in the second reactor.

Over a period of about eight hours, an additional 25 grams of hydrazine solution and 20 grams of sodium hydroxide were added to the ethanol-containing filtrate being recycled in the second reactor. As a result of this process, 49 grams of sodium azide were produced, which amounted to a overall yield of this product of 75.4%."

http://www.freepatentsonline.com/5098597.html

The only thing I can figure is that perhaps the temperature of your water, and the one used to determine its solubility is different -- it might be more or less soluble at a higher or lower temp.. big enough to make a difference.

Also, perhaps it was the for anhydrous or hydrated form? If you have a different hydrate then theirs, perhaps this would explain the solubility differences?

Also it is important to note that the hypochlorite reacts with CO2 to produce the carbonate and chlorine gas. If it is very old or has a porous package, perhaps that is what happened?

Personally, I would consider doing a titration on it in one way or another. Not to sure the best way to titrate calcium hypochlorite.

Also, perhaps it was the for anhydrous or hydrated form? If you have a different hydrate then theirs, perhaps this would explain the solubility differences?

Also it is important to note that the hypochlorite reacts with CO2 to produce the carbonate and chlorine gas. If it is very old or has a porous package, perhaps that is what happened?

It's come as dry granules as like commercial CaCl2, i just bought it but may be it has been very old at the supplier. Now i believe this Ca(ClO)2 quality is bad.

Personally, I would consider doing a titration on it in one way or another. Not to sure the best way to titrate calcium hypochlorite
Insert Quote
Add it to water with KI, then add acetic acid and titrate liberated iodine with thiosulfate.

Ah...yes, by this way the concentration can be determined and i still can use it.
Thanks.

Did it not come with one? You can make do without one as below but really need to be careful you get the cotton wool right, you can also make them out of coffee filters ect. The most trouble free route will be buy a pack of cotton thimbles they are cheap and will be hassle free, but if you are prepared to get ghetto cotton wool will work in a pinch.  ;

http://en.wikipedia.org/wiki/Soxhlet_extractor

Thankyou Naf1. I just went ahead and did a extraction with out it. Just a small experiment with about 40 grams of plant material. Distilling off ether to see how many mls of EO I have. Is working with ether and a hot plate safe? I have a box fan blowing on the whole set up.

You do not have to put much heat to ether to get it refluxing, smaller amounts boil by itself on a warm day when I open the lid. If the vapor is being taken away properly it is somewhat safe, if you can smell ether in the room I would stop straight away. And put a hose or tube on the end of your condenser and run the other end out of the window (or whatever) just for the ether reflux's.

Yeah if you warm it like Sedit said, it will eventually go into solution with stirring(15 min). So if you are patient you can determine how high a concentration by weighing correctly, if not so patient do as Sedit said and dissolve as much as you can in the time you are willing to wait then filter and titrate a sample.

It may be possible to repair it, but I don't think it would be very safe at all. I understand that glass needs to be annealed to be very decent, especially when it comes to structural integrity. I would look into glass blowing.

Is it still functional to any degree?