What is the difference between molecular distillation and film separation?

Molecular distillation technology and membrane separation technology are two different separation methods. 
The principles are different:
Molecular distillation technology separates based on differences in the mean free path of molecular motion.
Membrane separation technology uses the selective permeability properties of membranes to achieve separation.

The scope of application is different:
Molecular distillation technology is suitable for the separation of high boiling point and heat-sensitive substances.
Membrane separation technology can be used to separate a variety of substances, including dissolved and suspended solids in solutions.

Operating conditions vary:
Molecular distillation is usually performed at lower pressures and lower temperatures.
The operating conditions of membrane separation are relatively mild.

The separation effect is different:
Molecular distillation technology can produce high-purity products.
The separation precision of membrane separation technology is relatively low.

Equipment costs vary:
Molecular distillation equipment is generally more expensive.
The cost of membrane separation equipment is relatively low.

Different application fields:
Molecular distillation is mainly used in chemical industry, medicine, food and other fields.
Membrane separation is widely used in water treatment, bioengineering and other fields.

Both technologies have their own advantages and disadvantages. In practical applications, it is necessary to choose the appropriate method according to specific separation requirements and conditions.