Removing Stain on Painted Cement Floor

Try straight vinegar, preferably white vinegar. Leave it on the stained area for at least 30 minutes. Hopefully, the white stain will wash off!

Have you tried soap & water or pine oil?If it did not work try the below.

For a safe, chemical-free way to clean your cement floor, I would recommend scrubbing it with baking soda. Use a scrub brush and hot water. For stubborn stains, make a paste with baking soda and water and allow it to sit on the stains for a few hours. Once you have the stains removed, you may want to seal the concrete to prevent future staining
good luck.