Hull: (4) 26
Tries: Briscoe, Carvell, Domic, G Horne, Tony
Goals: Cooke 3
Catalans: (6) 12
Tries: Jones, Bosc
Goals Frayssinous 2
Hull shrugged off Catalans' spirited resistance with a glut of late tries to maintain their grip on second place.
The vibrant visitors took a surprise 6-4 lead at half-time with Stacey Jones crossing for a converted try, Shaun Briscoe going over for the hosts.
But Hull stepped up a gear after the interval, Gareth Carvell, Sid Domic, Graham Horne and Motu Tony all scoring to seal a 17th victory in 18 games.
Thomas Bosc grabbed a late second for Catalans but they remain bottom.
Hull coach Peter Sharp:
"We're confident and we'll be determined to play well next week at Warrington to make sure we finish second. "I see finishing second as massively important because you get two bites of the cherry in the play-offs and that's a massive advantage.
"We lacked energy and commitment in the first half and we under-budgeted mentally. We paid the price for it but that was a good lesson for us going into the play-offs."
Catalans coach Mick Potter:
"I'm very happy with our effort and the scoreline probably didn't reflect how close the game was. "It could have been closer and it was nice to get over the line for a consolation try at the end.
"I just don't think the guys are getting rewarded for their efforts. But I'm encouraging them and not being too hard on them and hopefully the wins will follow."
Hull: Tony, Briscoe, Domic, Yeaman, Raynor, Cooke, R. Horne, Dowes, Swain, Carvell, Radford, McMenemy, Washbrook.
Replacements: King, Whiting, G. Horne, Wheeldon.
Catalans Dragons: Bosc, Murphy, Sadaoui, Hughes, Verges, Frayssinous, Jones, Beattie, Rinaldi, Chan, Fakir, Hindmarsh, Mounis.
Replacements: Fellous, Griffi, Berthezene, Touxagas.
Referee: R Silverwood (Dewsbury)