If you are talking about the emancipation of slaves in the United States, then I think that what you are referring to is the plan to get rid of emancipated slaves by shipping them off to other countries. In the United States, the main plans centered around shipping the freed slaves to various places in Africa. This sort of plan actually happened to some extent in the case of Liberia. That country was founded by freed slaves who were sent "back" to their ancestral continent.
At least in the US, this was more often referred to as "colonization" than as "immigration."