Gas-liquid reactions are very common in Chemical Process Industry and contribute to more than 30% of all the chemical commercial reactions. There are several commercially important reactions where the gas phase is pure/explosive/toxic. In all these cases the gas phase is expensive and complete utilization of the solute gas is desired. When gas is introduced into the liquid, it has a certain residence time after which it leaves the liquid phase and is lost to atmosphere. To prevent this, there are often recovery devices attached in series with gas liquid contactors. However, this requires additional cost of installation of recovery devices and operating costs from recovering, pumping and compressing of recovered gas. The problem of retaining gas within the reactor has been achieved in the recently developed novel reactor design. It uses the self induction principle for impellers. Energy efficient impeller designs have been developed for gas induction and gas dispersion. It is also efficient for gas-liquid-solid three phase reactions. The solid phase may be a catalyst or undergo a chemical reaction. The solids concentration may vary from 0.005% v/v (in the case of noble metal catalyst) or 25% v/v (when solids undergo chemicals reaction). It is a proven design and a large number of reactors are in successful Commercial operation with a size range from 500 to 20,000 liters.