Summary
Synthesis of nano copper by reducing copper sulfate with ascorbic acid in water to produce fine copper particles, then drying to obtain a catalyst for organic reactions. The process uses saturated solutions, microwave acceleration, filtration, and ethanol drying to yield 1.92 g of dry copper (≈48% from starting copper sulfate). The nano copper reacts rapidly with concentrated nitric acid, generating toxic nitrogen dioxide fumes.
Key steps
- Prepare saturated copper sulfate solution (adjust for hydration state; exothermic with water).
- Prepare saturated ascorbic acid solution in water.
- Combine solutions to form a green mixture; copper begins depositing as orange, sparkling particles on the surface and in solution.
- Accelerate the reaction with microwave heating (800 W) until boiling; repeat cycles to build copper deposit (4–5 cycles).
- Filter to collect copper; wash with warm water to remove residual copper; filter again.
- Dry the copper on a suction pump; wash with absolute ethanol (two washes) to remove remaining water; filter and dry thoroughly.
- Product: 1.92 g of dry nano copper (≈48% yield from starting copper sulfate); yield limited by decreasing concentrations.
- Test reactivity with concentrated nitric acid (68%): fast reaction with dense brown NO2 fumes.
