[abdulloh]

What's the best chemical compound and its best proportions to remove and clean greasy dirt or very dirty grease

[OrganicDan96]

I don't quite understand do you want to remove grease from something or remove dirt from grease?

[abdulloh]

remove full-of-dirt grease or full-of-grease dirt from something

[Corribus]

To large degree it depends on what you're removing grease from. What might be used to clean grease off marble or steal may not be able to remove grease from a fabric or an biotic surface. Or maybe it could, but not without damaging the fabric/surface. It may also depend on the grease, which isn't very specific.

[OrganicDan96]

there are quite a few solvents you can use for this, I use petroleum ether to clean up paraffin oil from my fume hood when i use oil baths.

[Enthalpy]

Acetone and trichloroethylene dissolve "greases" well, but they dissolve many substances you may want to spare, like ABS, fabrics... So have a trial before.

Also, protect your skin, which needs its greases to be healthy. And beware allergies (I've seen an impressive one with acetone), fire risk, toxicity depending on the amounts and practices.