On Thu, 04 Oct 2018 08:21:22 -0500, CRNG wrote:

> Try taking the sponge, rinsing/squeezing it in plain water a couple of
> times. Then place the soaked sponge on a disk and place in microwave.
> Heat until the soaked sponge starts to boil off water. Remove
> plate/sponge and let cool.

The microwave seems like a good idea, if it doesn't destroy the sponge.