Compared to bubble columns

the mixing performance in an airlift loop reactor is significantly improved due to the presence of regular fluid flow

which has been widely applied in many chemical processes

such as fermentation and crystallization. Therefore

it has become a hot research topic in recent years. The flow regimes

hydrodynamic characteristics (including phase holdup

circulation velocity

mixing time and segregation index) and mass/heat transfer characteristics are reviewed in this paper. The influence of dispersed holdups

especially that of solid on the key parameters in the reactor

such as circulation liquid velocity and chemical reaction rates

is analyzed. In addition

a perspective is given on multi-disciplinary study of multiphase flow

mass/heat transfer and chemical reactions with mechanistic models in order to promote the industrial application.