Question: Yesterday I did put some water with a dissolved soap in an aluminum pan. I think the soap is a Dove like this one: <https://www.dove.com/content/dam/unilever/dove/brazil/portuguese/pack_shot/front/skin_cleansing/skin_cleansing/sabonete_dove_original_90g/fop_original_90g_derm_seal_-_83344562-1147482-png.png.ulenscale.490x490.png> It stayed there for many hours. Now when it was going to be used for cook, a mildly strong soap smell remained on it. It was then washed with water to try to remove it. Then, some vinegar was used somehow during some time (I didn't use it) to try to remove it without success.

What are the options. Use hot water? Sunshine? Lemon?. Vinager for a longer time period ? sodium bicarbonate ? What else might work.

Thank for the answers.

Answer: 
I would ask you to try using butter (not margarine) to neutralize the residual odour of Dove™ skin cleanser.

The butter is an intermediate step. The concept is that the fats in the butter will bond with the organic base of the "soap" film coating the aluminum pan. When removed, the butter will pull the odour with it. The butter is then removed as you normally would remove food residue. 

* At room temperature, rub a small amount of butter (1-2 teaspoon) over the dry surface of the pan. Work a thin layer over the whole pan into every crevice.  

**Note**: I used warm *GHEE* (clarified butter) and applied it with my fingers.
* Wipe the pan dry with a paper towel. (To remove the butter.) Be thorough.
* Wash the pan as you would after normal use.

Good luck

UPDATE: This did not work with a plastic cup that I used for the experiment. When dry, the odour returned. You may have better results with better your metal pan.
Facial soap like Dove contains oils that adhere to the skin as a surface film, and to the container with which the soap and water mixture has come in contact.
You can remove that film by scrubbing with scouring powder or another soap that does not contain oils- like dishwashing liquid, which is designed to remove oily films.