Would diffusion occur at absolute zero?

No. The definition of absolute zero is that it is the (hypothetical) point at which all molecular activity stops. The definition of diffusion is the intermingling (motion) of molecules caused by thermal agitation. If the molecules aren't moving, diffusion cannot occur. read more

Diffusion occurs because of the kinetic energy of the molecules or atoms involved. At absolute zero degrees, diffusion will not occur because atoms/molecules ar no longer moving. read more

2) Diffusion always occurs, sometimes faster, sometimes slower. 3) Diffusion does not occur at a temperature of absolute zero. 4) Gases are exchanged by diffusion. read more