Preparation of copper oxide nanocrystal and its catalysis performance in phenol oxidation

Copper oxide nanocrystals were synthesized through a precipitation method and were characterized by means of XRD, TEM and N ₂ adsorption-desorption. The results showed that the average crystallite size of the copper oxide nanocrystals was 8.5 nm and the specific surface area was 56.2 m ²/g. The catalytic performance of the copper oxide nanocrystals in oxidation of phenol with oxygen to dihydroxybenzene was studied and the reaction conditions were optimized. It was found that the effects of catalyst concentration, ascorbic acid concentration, acetic acid volume fraction and reaction temperature on the didydroxybenzene(DHB) yield were significant. The DHB yield could reach 14.90% under the optimal conditions:phenol concentration 1.28 mol/L, copper oxide catalyst concentration 0.572 mol/L, ascorbic acid concentration 0.796 mol/L, 20%(ψ) acetic acid solution 50 mL, oxygen flux 70-80 mL/min, reaction temperature 308 K and reaction time 90 min.