Two is correct I believe. It sounds pretty weird though... like in a TV commercial. I'd say this: ... surface, so that they can be easily cleaned. ... surface to be able to clean them easily. These structures are day to day English. There may be others by changing the structure of the sentence. I hope this helps. Cheers!

For my part, the second one is more natural.

Neither option is wrong but #1 is poor and #2 is excellent. #2 is an excellent sentence because "for ease of cleaning" precisely describes the reason why "we chose kitchen tiles with a smooth surface". "For" indicates that a reason is being given. The sentence is perfect. #1 is a poor sentence because "to clean easily" does not precisely refer to anything in the first part of the sentence. It can be fixed as follows: "We chose kitchen tiles with a smooth surface so that we could clean them easily" Now the references are clear. "Them" refers to the tiles. "So that" indicates that you are giving a reason for "we chose". Or, you could say "We chose kitchen tiles with a smooth surface so that we could clean it easily" which is the same except that "it" now refers to "surface". Or, you could simply say "We chose kitchen tiles with a smooth surface so that we could clean easily" which is not as good but still better than your first sentence because "so that we could" creates a bond with the first part of the sentence.

We chose kitchen tiles with a smooth surface for easy cleaning. We chose kitchen tiles with a smooth surface to make them easier to clean.

Hie Daniel. I think the first answer sounds more natural: we chose kitchen tiles with a smooth surface to clean easily I hope this helps🙂