[rrayyangar]

in the sodium azide manufacturing :    in the mixture of hydrazine hydrate and methanol   and caustic soda flakes dissolved   and  passing methyl nitrite gas what is the optimum temperature to be maintained in the reaction to have best yield of sodium azide

[TheUnfocusedOne]

You're going to need to show your attempts bud. It's in the forum rules, sorry.

[AndersHoveland]

Hopefully this helps:
 
Information about Hydrazoic Acid, HN3

Anhydrous hydrazoic acid (formula HN3 ) boils at 35.7degC, and has a freezing point of (minus) -80degC. This liquid gives of extremely poisonous fumes with a sharp corrossive unbearable smell, somewhat comparable to that of NO2. However, concentrations of fumes below the odor threshold are easily sufficient to cause poisoning. The liquid gives off vapors which can initiate explosion of the liquid if there is any nearby flame.

The actual creation of azides is difficult in the laboratory, but it can be carried out. Azides are as poisonous as cyanide, even sodium azide can give of some HN3 fumes when dissolved in water. Acids should not be added to basic azides, highly poisonous HN3 gas will result, and this gas has the potential for explosion. There are basically two routes, from sodium amide, or from hydrazine. The chain of reactions either way is long and complex.

Hydrazoic acid can act as either an oxidizing agent or reducing agent. For example, it reacts with copper according to the following equation:
(3)HN3 + Cu --> Cu(N3)2 + NH3 + N2

 
Preparation of Sodium Amide

Sodium and dry ammonia, when heated to 320-350degC, react to form sodium amide and hydrogen.
 
Metallic sodium dissolves in cold anhydrous liquid ammonia to form a deep blue colored solution. If Sodium Ferrate (which acts as a catalyst) is added to a blue solution of sodium dissolved in ammonia, the solution will slowly turn to a bronze color as all the sodium reacts.

Sodium and anhydrous liquid ammonia react, rather than simply dissolve into the typical blue solution, with the use of a black catalyst prepared originally by the reaction of a ferric salt with oxides of sodium in liquid ammonia. Liquid ammonia (500ml) was stirred at -32C and treated with 0.3g Fe(NO3)3 hexahydrate and then with 1g of metallic sodium. Air was bubbled through the mixture to discharge the initial blue color and produce a black precipitate of catalyst. Additional sodium 24g, added portionwise was then consumed in about 20 minutes with dissappearance the blue colour and formation of a grey suspension of sodium amide. The solubility of sodium amide thus prepared is very low (about 1mol per liter of liquid ammonia).
 

Azide from Sodamide

Sodium azide has been prepared by passing nitrous oxide over sodamide heated to 230degC.

2 NaNH2 + N2O → NaN3 + NaOH + NH3
 
Nitrous oxide can be generated by the gentle heating of small ammounts of ammonium nitrate until decomposition, traces of nitric oxide and nitrogen dioxide are also produced, these can be eliminated by bubbling the gases into a solution of sodium carbonate, leaving only nitrogen and nitrous oxide. Sodium nitrite will be produced in the solution. Depending on the ratio of NO2 to NO in the decomposition products, sodium nitrate may be the main byproduct forming, or some of the nitric oxide may not be absorbed by the basic solution, where it will either react with air to form nitrogen dioxide, or in the absence of air the unstable gas will decompose into nitrous oxide and nitrogen gas within several minutes.
 
Sodium nitrate can also be reacted with sodamide, both dissolved in anhydrous liquid ammonia under pressure at a temperature of 100degC to produce the dissolved azide. This is dangerous since the pressurized container is likely to burst since anhydrous ammonia has a boiling point of only (minus) -33degC. The reaction can take place at 80degC, while heating to 135degC allows a shorter reaction time and gives higher yields. First the two reactants react to form nitrous oxide, and then the intermediate nitrous oxide reacts with more amide.

KNO3 + 3KNH2 → KN3 + 3KOH + NH3
 
 
Another method is to react a dispersion of sodium amide in a hydrocarbon solvent with isopropyl nitrite dissolved in a hydrocarbon solvent. Excess amide should be used, and the solution of nitrite should be gradually added to the amide dispersion, with rapid stirring.
 
The below might be a possible reaction:
 
(13)NaNH2 + (6)PrNO2   →  (2)NaNO2 + (3)NaN3 + (6)NaOPr + (2)NaOH + (8)NH3
 
where NaNH2  is sodamide, and PrNO2  is the nitrite ester of isopropanol. NaN3 is sodium azide and
NaOPr is sodium isopropoxide, which is analogous to sodium methoxide.
 
Ispropyl Nitrite can easily be made by adding concentrated HCl solution cooled to 0degC to a cold solution of sodium nitrite and isopropyl alcohol.
 

Azide from Hydrazine

Hydrazine hydrate can be converted to anhydrous hydrazoic acid by reaction with a nitrous acid ester in ether at 0°C with some sodium ethoxide present.
 
Hydrazoic acid HN3 can also be obtained by the action of nitrous acid on hydrazine sulphate.
(W. Wislicenus, Berichte, 1892, 25, p. 2084)

Hydrazine sulfate reacts with a solution of hydrogen peroxide and sulfuric acid to produce hydrogen azide gas in up to a 28% yield. It is important that the reactants be free from any traces of dissolved copper ions.

Possible Unusual Method
Supposedly, by heating finely powdered sodium nitrite in a fusion of excess urea at 160degC, low yields of sodium azide can be obtained, but I cannot confirm this with any certainty.