The Reds had all but sealed their last-eight spot with a memorable 5-0 triumph in the first leg at the Estadio do Dragao last month, and they comfortably saw out the second half of the tie on Merseyside to enter next Friday's draw with minimal fuss.
Sadio Mane came closest to a goal on the night when he hit the post in the first half, but Liverpool never needed to get out of second gear as they made it 14 European home games without defeat to become the first English side to make it through to the quarter-finals of this season's competition.
Liverpool boss Jurgen Klopp insisted before the match that he would not make wholesale changes despite facing Manchester United in a crucial Premier League showdown on Saturday, and sure enough the likes of Roberto Firmino and Mane - the hat-trick hero from the first leg - were once again included.
One of those saw Iker Casillas included for his unparalleled 171st - and likely final - Champions League appearance, but the experienced shot-stopper was barely tested in a first half which saw both sides fail to register a shot on target.
Liverpool did occasionally threaten to break the deadlock, though, and two of those came through Mane as first he showed impressive athleticism to turn Joe Gomez's dangerous cross narrowly over the crossbar after it had just eluded Firmino.
The winger came even closer shortly after the half-hour mark when James Milner floated a perfectly-weighted pass over the top which Mane controlled on his chest before drilling a low strike past Casillas and against the inside of the post.
Dejan Lovren was the only other player to look like scoring when he looped Milner's free kick onto the roof of the net, but despite both teams having scored 105 goals in 41 matches across all competitions heading into the match, the first half ended goalless and was more akin to a training contest than a Champions League knockout tie.
The hosts did make a brighter start to the second half and threatened within two minutes of the restart when Jordan Henderson, Alberto Moreno and Adam Lallana all combined to tee up Milner, who was at full stretch and could only slice his effort wide of the target.
Porto's first shot of any note also provided the first shot on target of the match in the 52nd minute when Abdul Majeed Waris held off Gomez and was afforded room to shoot from outside the area, but Loris Karius was equal to his effort.
Liverpool continued to control possession, though, and they almost added to their first-leg lead shortly before the hour mark when Firmino raced through on goal only to be denied by a sliding challenge from Felipe.
With his side cruising to victory on aggregate Klopp took the opportunity to rest Firmino for Danny Ings, and the sub drew a routine stop from Casillas five minutes after his introduction having got on the end of Henderson's cross.
Salah was also introduced as a replacement for Mane in the final 20 minutes, and the free-scoring Egyptian almost made an immediate impact when he picked out Milner with a cross, only for the midfielder to steer his header straight at Casillas.
Sights of goal began to arrive more frequently in the closing stages, and Porto had a rare chance 11 minutes from time when Jesus Corona ducked inside before dragging his shot wide of the near post when he should have done better.
Salah had one sight of goal during his short time on the field but could not beat Casillas from a tight angle, before Porto almost nicked a win on the night when the ball dropped to Oliver Torres inside the area, only for Lovren to make a crucial block to deny the midfielder from close range.
Moreno and Ings both had late chances to earn Liverpool a fifth consecutive win, but Casillas kept the latter at bay to record a clean sheet at the probable end of his illustrious Champions League career as Porto avoided further embarrassment in the tie.
Liverpool barely broke sweat having done the hard work in the first leg, and they will now look forward to next Friday's draw before facing arch-rivals Manchester United at Old Trafford on Saturday lunchtime.
LIVERPOOL (4-3-3): Karius; Gomez, Matip, Lovren, Moreno; Milner, Henderson, Can (Klavan, 80'); Lallana, Mane (Salah, 74'), Firmino (Ings, 62')
PORTO (4-4-1-1): Casillas; M Pereira, Felipe, Reyes, Dalot; Oliver, Andre (Oliveira, 62'), B Costa, Corona; Waris (R Pereira, 68'); Aboubakar (Paciencia, 80')