PLASMA SYNTHESIS OF TITANIUM DIOXIDE NANOPOWDER AND POWDER DOPING AND SURFACE MODIFICATION PROCESS

摘要

A process and apparatus for the synthesis of metal oxide nanopowder from a metal compound vapour is presented. In particular a process and apparatus fo r the synthesis of TIO~2 nanopowder from TICI~4 is disclosed. The metal compou nd vapour is reacted with an oxidising gas in an electrically induced RF frequency plasma thus forming a metal oxide vapour. The metal oxide vapour i s rapidly cooled using a highly turbulent gas quench zone which quickly halts the particle growth process, yielding a substantial reduction in the size of metal oxide particles formed. The metal compound vapour can also be reacted with a doping agent to create a doped metal oxide nanopowder. Additionally, a process and apparatus for the inline synthesis of a coated metal oxide is disclosed wherein the metal oxide particles are coated with a surface agent after being cooled in a highly turbulent gas quench zone.