I am in the midst of a series of paintings I call my “Winter Tree Series.” On this particular drawing, I made a big blotch with some dark green dye, right where I did NOT want it. Before the dye dried, I attacked it with some rubbing alcohol. 
The alcohol loosened the dye spot, and dispersed it. The dye moved to the edges of the alcohol spot, mostly, though it did lightly dye the whole area. In order to gain a lightening of the distracting dye blotch, I did have to sacrifice control over this portion of the painting.
The area with the alcohol is drying- it will be a darker portion than the rest of the painting in progress. I will probably choose to paint the sky area a medium grey blue now! Still, the unwanted dye blotch is gone. Victory!
Let's talk silk painting! 
ohhh this is fabulous – so interesting – so glad you sharing your process. I would like to invite you to join us on my blog’s Off the Wall Friday – where textile artists share their creative endeavours – its easy to link and we all find it motivating and inspiring! The link is open till Sunday.