College of Materials Science and Chemical Engineering, Zhejiang University, Hangzhou 310027, China;
In this paper, the removal of trace carbon dioxide from closed spaces through membrane process and biotransformation are introduced in detail. These methods include the microalgae photobioreactor, membrane microalgae photobioreactor, supported liquid membrane, membrane gas-liquid contactor, hydrogel membrane, and enzyme membrane bioreactor. The advantages and disadvantages of these methods are compared. It is found that higher CO removal efficiency can be obtained in biotransformation and membrane process. However, a large volume and high energy consumption are needed in biotransformation, while the low permeability and stability must be solved in the membrane process.