Membranes

From The Book of THoTH (Leaves of Wisdom)

A membrane is a thin, typically planar structure or material that separates two environments. Because it sits between environments or phases and has a finite volume, it can be referred to as an interphase rather than an interface. Membranes selectively control mass transport between the phases or environments.

Biological membranes

Biological membranes include:

• Cell membrane and intracellular membranes
• mucous membrane
• S-layer
• membranes such as serous membrane and mesothelium that surround organs, including:
  • the peritoneum that lines the abdominal cavity
  • the pericardium that surrounds the heart
  • the pleura that surround the lungs
  • periosteum, membrane that surrounds bone
  • the meninges that surround the brain: the dura mater, arachnoid mater, and the pia mater

Artificial membranes

Artificial membranes are used in:

• Reverse osmosis
• Filtration (Microfiltration, Ultrafiltration)
• Pervaporation
• Dialysis
• Electrodialysis
• Emulsion liquid membranes
• Membrane-based solvent extraction
• Membrane reactors
• Gas permeation
• Supported liquid membranes

Artificial membranes are manufactured in two main geometries: rectangular and cylindrical. The rectangular geometry is utilised in the construction of flat-sheet, disc, spirally-wound, plate and frame and cartridge modules, while the cylindrical geometry is found in tubular and capillary or hollow-fibre modules.

Theoretical membranes

Theoretical membranes are used in:

• M-theory (simplified)