Practical Organic Chemistry

Duma's method.
The nitrogen containing organic compound, when heated with CuO in a atmosphere of CO2, yields free N2 in addition to CO2 and H2O.
‌CxHyNz+(2x+‌

y

2

)‌CuO→
‌‌‌xCO2+‌

y

2

H2O+‌

z

2

N2+(2x+‌

y

2

)‌Cu
Traces of nitrogen oxides formed, if any, are reduced to nitrogen by passing the gaseous mixture over heated copper gauze.