To regenerate activated carbon you rinse thoroughly with hot distilled water to remove impurities then bake in an oven to re-activate the adsorption (not absorption - the difference is important) properties.
…. Adsorption is micro particles being captured in surface crevices of a filter medium such as activated charcoal. Absorption is the addition of a material into another be osmotic pressure or capillary action.
Charcoal adsorbs microscopic rust particles. Paper towels absorb spilled water.
The dishwasher will not regenerate your charcoal where it will adsorb contaminants again but WILL get carbon fines all over the inside of your dishwasher. …. Remembering a teenager that tossed a Brita pitcher in the dishwasher with the filter still installed. The youngest opened the dishwasher after the cycle and came running, “Daddy, the dishes have FLEAS!”