The Italian, who moved to the Premier League outfit in 2009, failed to make an impact at the club, which prompted a season-long loan at AC Milan last year.
Despite the 28-year-old's agent claiming that the playmaker was due to stay with Liverpool this summer, the club announced his departure to Serie A last week.
"I had no doubts about Fiorentina because they wanted me and the project here is very interesting," Sky Sports News quotes Aquilani as saying.
"Now the most important thing is that I will never return there and I want to concentrate on my new cycle."
Aquilani made just 30 appearances for Liverpool during his three-year stint at the club.