Salah takes his place among the 19 travelling players who departed John Lennon Airport on Tuesday afternoon for Belgium after missing Sunday’s 1-1 draw at Manchester United.
However, Alexander-Arnold remains on Merseyside due to a virus, as does Matip, who has a sore knee.
Liverpool squad: Alisson, Fabinho, Van Dijk, Wijnaldum, Lovren, Milner, Keita, Firmino, Mane, Salah, Gomez, Adrian, Henderson, Oxlade-Chamberlain, Lallana, Brewster, Robertson, Origi, Kelleher.
After a win and a defeat in Group E so far, Jürgen Klopp’s side face the Belgian title-holders away from home in the first of back-to-back meetings between the clubs.
Liverpool trained at Melwood on Tuesday afternoon before flying to Belgium for Wednesday’s 8pm BST kick-off at KRC Genk Arena.