A few weeks ago I had a major 5 quart oil spill on my garage floor. I cleaned it with cat liter, pressure washer and it took an entire afternoon. My problem came when one stubborn spot (2ft by 2ft) I tried to remove by pouring vinegar on it. Now that spot is white and looks like if you had spilled battery acid on it. Is there something to fix that spot so it matches the rest of the concrete again?

