The invention relates a method for storing a solution of methane and a C2-C30 hydrocarbon, the method comprising: mixing gaseous methane and a C2-C30 hydrocarbon to provide a mixture of methane and C2-C30 hydrocarbon, wherein the mixture comprises greater than or equal to about 50 mole percent of methane; maintaining the mixture of methane and C2-C30 hydrocarbon as a liquid solution at a pressure of 30 to 150 bar within a storage vessel, wherein the storage vessel comprises a porous adsorbent framework. The invention also relates to similar methods for storing hydrogen, nitrogen and carbon dioxide. The invention also relates to the use of a non-polar solvent such as a hydrocarbon for storing a non-polar gas in a porous adsorbent framework.