Nitromethane synthesis.
I took the liberty of posting this synth for the fact that i have read several posts concerning the level of castor oil in the nitromethane RC fuel, and not to mention the % of nitromethane in RC fuel anyway.
I hope it is useful, if not it will just fade away amoung the many others.." in the hive.
I have not performed this synth but has been extracted from a academic source.
To a mixture of 125g (1.33 mol) of chloroacetic acid and 125g of crushed ice contained in a 1000ml 2 neck RBF, add, with stirring or shaking, sufficient 40% sodium hydroxide solution to render the solution faintly alkaline. About 90ml required.
The temp should not be allowed to rise above 20'C degrees, or else sodium glycolate will form.
Introduce a solution of 91g (1.3 mol) of pure sodium nitrite in 100ml of water into the flask. insert a thermometer well into the liquid by means of a screw capped adapter fitted in the side neck. Attach a still-head fitted with an efficient condenser set for downward distillation. (the receiver should be cooled in ice-water)
Heat the mixture slowly until the first appearence of bubbles of carbon dioxide(this occurs when the temp has reached 80-85'C. immediately remove heat source".
The reaction (decomposition of the sodium nitroacetate) sets in with liberation of the heat and the temp rises to almost 100'C without further application of external heat.
Note) if heat is applied once the temp reaches 85'C the solution will begin to froth and a loss of nitromethane will occur.
Result: ~30ml of nitromethane and 40ml of water, distill over.
When the exothermic reaction apparently ceases (temp below 90'C, heat the mixture (gently) until it rises to 110'C.
transfer the distilate to a sep funnel, allow to stand for ~30min to complete the seperation of the two layers and remove the lower layer being nitromethane".
Dry it with anhydrous calcium chloride or an calcium sulphate and distil:
30g (37%) of nitromethane, bp 100-102 are obtained.
Ref: A, Vogel (1978) Vogels textbook on Practical organic chemistry.