dry ice in ice cream maker 5061

forever I not hospital thinking it batches

the mechanism desired is heat transfer - related to temperature difference, rate of transfer, and size of sink.

1) Heat of sublimation is the heat absorbed when the material goes from solid to gas. While dry ice uses that property readily, it is less common in water (e.g., ice cubes left in the tray subliming)

When ice is in water, it is the heat absorbed in transfer from solid to liquid that counts (its latent heat of fusion) not its heat of sublimation.

So in effect, the heat sink comparison is dry ice sublimation vs ice melting. But that is only one part of the process.

2) The heat needs to be rapidly moved from the mixture. Liquid ice-water is much better at heat transfer than even the coldest air, by orders of magnitude. First, because it is a liquid and thus also uses conduction rather than just convection (i.e., it absorbs more heat because it is a much more effcient mechanism). Second, because water has a much higher heat capacity than air (i.e., it absorbs much more heat per volume when it is in contact).

3) dry ice is 190 K roughly (memory here) vs water-ice-salt at 265 K. While the dry ice temperature of sublimation is lower than the water temperature of fusion, it does not compensate for its other poorer parameters.

you are correct.

and the