Most scholars would respond, I believe, that this is largely a speculative argument based on a very few sources, all of which are questionable in terms of origin and transmission. The most important is probably [Herodotus] (http://http://www.shsu.edu/~his_ncp/Hanno.html). Herodotus is justly seen as a progenitor of historical studies, but his account of Hanno's voyage to West Africa is fantastical, as you can read,

The theory becomes even more problematic when we consider the fact that it was first seriously developed as a modern thesis during the colonial process of delegitimizing West African indigenous state and city formation, iron technology, etc. This process explains a motive for giving credit to Mediterranean peoples rather than sub-Saharan Africans for technological development, complex political structures, etc.

I don't think it's possible to disprove a Phoenician voyage to West Africa, but certainly there is no serious evidence -- linguistic, physical, documentary -- of "colonies" in West Africa.

Edit: Changed "falsify" to "disprove" because the term "falsify" in this case had two, confusing meanings.