What is Refutation and Rebuttal?
To rebut is to argue against the topic and attempt to prove that the opponent is wrong or saying something that is untrue.
To refute is to prove by evidence/ proof that the opponent is wrong and untrue in his evidence or assumptions.
So, basically Rebuttal is an attempt to prove something is not true whereas Refutation is actually proving that something is untrue.
In other words Rebuttal is a synonym of Refutation and are often confusing but the only difference is in the presentation of proof and reasoning which overthrows the claim or theory presented by the opponent.