Guangjin Chen

College of Chemical Engineering and Environment,China University of Petroleum,Beijing

Gas hydrate is a class of cage-like crystalline material in which host water molecules form polyhedral cage via hydrogen bonding and enclose guest molecules in them.Since the first find of chlorine hydrate in 1810,the research on gas hydrate has lasted more than 200 years.In the first hundred years,gas hydrate was interested only by scientists with curiosities,but now it has drawn attentions of people in wide fields,including energy,climate,water resources,process industry,etc.The requirement on preventing gas and oil pipelines from hydrate plugging supplied the first motivation from industries to gas hydrate research since 1930's.However,the greatest motivation is from the finding of huge natural gas hydrate deposits in ocean and permafrost region in recent decades,which have been considered as a new clean energy resource for human beings in future and a critical factor affecting global climate change.The developments of hydrate-based technologies,e.g.,gas(CH4,CO2,H2,etc.)storage in the form of solid hydrate,gas separation and desalination of sea water via forming hydrate,are also interested by gas hydrate community.Because of the motivation from industries and governments,gas hydrate community is growing rapidly and making great progresses in both fundamental and applied researches in recent decades.The annual number of research articles on gas hydrate has increased from about 100 to 1000 since the first international conference on gas hydrate held in 1993.Hence it is of significance to have a special issue mainly consisted of review papers to display the state of art of gas hydrate research.

The researchers from China,Canada,Ireland,India,and Singapore contribute 14 review papers and 7 full length articles to this edition of the Chinese Journal of Chemical Engineering,covering wide areas including the hydrate nucleation and growth mechanism,the inhibition mechanism of hydrate formation as well as the development of low dose of kinetic inhibitors,the exploration/exploitation of natural gas hydrate,the developments of hydrate based technologies such as separation of gas mixture and the storage natural gas.I would like to say thanks to all contributors and the editors of Chinese Journal of Chemical Engineering.I believe this special issue will be welcomed by gas hydrate community and promote the research in gas hydrate around the world.