Learned behavior isn't passed on through genes, so every generation needs to start from the beginning of learned behavior. You can't simply build on what you taught the previous generation. To get more intelligent chimps, there needs to be genetic changes. You could do this by breeding the most intelligent (and social) chimps, breeding the most intelligent of their offspring, and so on. How long this would take is anybodies guess, but probably somewhere between hundreds and tens of thousands of generations.

There is a little caveat here, though. If we try to teach chimps, we've altered their environment, and the environment is the driving force of evolution. If more intelligent/social chimps benefit from being taught such that their offspring are more likely to successfully reproduce--whether this is because they have more offspring or more of their offspring survive--then we've introduced an evolutionary pressure that selects for intelligence and socialness. However, we should expect this to take a very, very long time to produce results--probably millions of years.