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Yes, some did. Ironically, one of them was Roger B. Taney, US Supreme Court Chief Justice and author of infamous Dred Scott decision.
Contrary to popular believe, Robert Lee did not free his slaves - he did not own slaves. His father-in-law named Robert Lee an executioner of his will. According to this will, all his slaves should be set free in 5 years after his death.
UPDATE. I don't know if Roger Taney freed his domestic slaves, or they worked his land. But John Dickinson, founding father and largest Delawer farmer and slaveowner, freed his slaver by 1786. His farm moved from tobacco to less labor-intensive crops.