Raschig process

The Raschig process is a chemical process for the production of hydroxylamine, which is annually required in the multi-ton scale, for example for the production of caprolactam. It is named after the German chemist Fritz Raschig.

The starting materials are oxygen, sulfur dioxide, ammonia, carbon dioxide and water. First, ammonia is catalytically partially oxidized to form nitric oxide and nitrogen dioxide:

This gas mixture is then introduced into an ammonium carbonate solution:

The ammonium carbonate required is obtained by passing carbon dioxide into a solution of ammonia:

In the nitrite-containing solution, ammonia is converted to ammonium nitrite, in which carbon dioxide and water are regressed:

Ammonium nitrite is then reduced with sulfur dioxide to hydroxylamine wherein sulfur dioxide is oxidized to sulfuric acid in the aqueous environment. The resulting hydroxylamine is converted so directly to his salt of hydroxylamine sulfate ( NH3OH ) 2SO4:

The net equation of the overall process is thus:

Hydroxylamine can be released using a base:

A major disadvantage of the method is the high " drop " portion. Fall per tonne hydroxylamine at 4 tons of ammonium sulfate. 1967 led BASF and Inventa a procedure in which accumulates only half as much waste. Stamicarbon eliminated entirely 1970 ammonium sulfate ( Stamicarbon process ).

Swell

• Chemical- technical process
• Name reaction