Preparation of ZnO nanoparticles using blendes as raw material.

The synthesis of crystalline zinc oxide nanoparticles with closely- controlled size and morphology by a precipitation-pyrolysis route is described. Zinc sulphate and oxalic acid are used as starting materials to prepare zinc oxalate dihydrate. Control of the particle size of this precursor by means of the precipitation agent is important in the production of well-dispersed zinc oxide particles in the subsequent pyrolysis stage in which dehydration of the oxalate and formation of the zinc oxide occur; the kinetics of these reactions are discussed and optimum conditions determined. A hydrometallurgical route for obtaining zinc sulphate by sulphuric acid/iron (III) sulphate leaching of zinc blende (sphalerite) concentrates with recycling of all wastes is proposed as part of the flowsheet.
The synthesis of crystalline zinc oxide nanoparticles with closely- controlled size and morphology by a precipitation-pyrolysis route is described. Zinc sulphate and oxalic acid are used as starting materials to prepare zinc oxalate dihydrate. Control of the particle size of this precursor by means of the precipitation agent is important in the production of well-dispersed zinc oxide particles in the subsequent pyrolysis stage in which dehydration of the oxalate and formation of the zinc oxide occur; the kinetics of these reactions are discussed and optimum conditions determined. A hydrometallurgical route for obtaining zinc sulphate by sulphuric acid/iron (III) sulphate leaching of zinc blende (sphalerite) concentrates with recycling of all wastes is proposed as part of the flowsheet.