This review summarizes the research progress of separation technologies based on hydrate formation for both solution concentration and gas separation areas. It is found that

although single hydrate separation method shows to be relevant for seawater desalination

bioengineering

oil-gas separation

etc.

it still has some drawbacks such as concentrate liquid entrainment phenomenon

low separation efficiency

and/or high operation pressure among others which need to be solved to realize industrialization. For the separation of gas mixtures

the absorption-hydration and adsorption-hydrate hybrid separation technologies show some advantages compared to the single hydrate separation process. These two technologies have higher gas treatment capacity

higher separation efficiency

and/or could perform a continuous gas separation process

among others. However

some fundamental issues such as the flow characteristics of hydrate/oil slurry

or the interaction relationship between hydrate crystals and adsorbents

are still need to be measured or addressed for these two hybrid gas separation technologies. Furthermore

suggestions for further research of these separations are proposed. For solution concentration

methods like developing more efficient hydrate formation promoters

or coupling with some other separation technologies can be considered. And for gas mixtures separation

some directions such as founding more efficient hydrate formation promoters

obtaining the actual flow characteristics of hydrate/oil slurry when using water/oil separation media

determining the interaction mechanism between hydrate phase and adsorbents when using water containing porous materials

etc.

are proposed.