Patent ID: 7371343

Claim:
A nano-powder extraction apparatus by the rotation of hollow impellers comprising: a collecting device having a tank charged with a surfactant solution, the tank being provided at its side wall with a plurality of powder extraction pipes installed at different heights, and with solution inlet and outlet ports; and a gas supply device mounted inside the tank and adapted to supply gas containing nano-powder into the solution charged in the tank so that the gas is swirled and uniformly distributed into the solution, the gas supply device having a rotatable drive shaft penetrating vertically through the tank, the rotatable drive shaft being formed at its lower portion with a gas supply hollow bore connected at its lower end to a gas injection device for receiving the gas therefrom, the gas supply device also having at least one supply impeller horizontally mounted around the rotatable drive shaft at an upper end of the gas supply hollow bore, the supply impeller being formed with a plurality of hollow diffusion holes communicating with the gas supply hollow bore, wherein the supply impeller comprises a circular plate fixed to the rotatable drive shaft, and a plurality of arc-shaped projection blades extending upwardly and downwardly from upper and lower surfaces of the circular plate while being radially arranged with equal spacing, each arc-shaped projection blade defines a diffusion hollow hole therein.