video tutorial Nitrourea preparation scaled up

Overview: Scale-up synthesis of nitro urea starting from urea via formation of urea nitrate with nitric acid, followed by nitration with cold sulfuric acid to yield nitro urea. Emphasizes temperature control, stirring, and filtration steps; obtained ~31 g nitro urea (~70% yield from starting urea) with some residual moisture and acid.

Process steps

• React 25 g pure urea with ~32 mL of 68% nitric acid to form urea nitrate, crystallize.
• Filter and dry to obtain ~55 g urea nitrate (some water/acid remains).
• Mix urea nitrate with 150 mL of 98% sulfuric acid in an ice bath, adding gradually while keeping temperature below 0°C (about 40 minutes).
• After addition, dilute slowly with ice to ~350 mL total volume, filter the nitro urea, wash with ice-cold water, and dry to about 31 g nitro urea (roughly 70% yield).

Safety/observations: Nitro urea rapidly decomposes when heated but does not explode without a shockwave; large-scale reactions require strong cooling and careful control to prevent decomposition and yield loss. Final product is fairly dry but still slightly damp.