The present invention relates to a superhydrophilic biodegradable cross linked foam membrane and a process for preparation of said foam membrane from a seaweed polysaccharides by blending with amino biopolymers/amino acids/proteins/amino compounds followed by crosslinking with a naturally occurring cross linker, genipin. The foam membrane can be used as a substitute for synthetic membrane for varied applications including membrane separation for oil-water emulsions, oil-water mixtures and other aqueous-organic mixtures under ambient conditions. These foam membranes can be recycled and reused more than three times without considerable decrease in flux rate and stability. The separation methodology of the mixtures using the foam membrane of the present invention is gravity-driven and therefore, simple and energy-efficient.