Paint over Wallpaper

I have this pipe on my roof. I guess it's some sort of exhaust/ventilation pipe. As you can see it's (i) metal and (ii) rusty. What I want to do is (i) remove the rust and (ii) paint it Reasons for doing it is (i) aesthetics and (ii) I don't want the pipe to rust through and fall apart. Not sure whether it's likely in the next 5-10 year but since I live in a humid area I presume it might happen. Questions: 1. What type of chemical should I use to remove the rust? 2. What type of paint should I use? Thx!

Hi folks, Just wanted to ask others opinions on this issue. I know most painters would say to repaint the entire surface when dealing with semi or full gloss paints, but I just wanted to know if there was a trick to blending semi gloss touch ups? In my early paint days, I used to feather out the paint over nail heads or marks on the wood, but of course, as it sets, you see dry wave lines where the paint has been "dragged" and dries too quickly to leave a smooth gloss skin. So, in recent times, I ditched the feathering approach and went with a smooth touch up patch without feathering, which doesn't show any "non gloss" issues, but can be singled out due to a slightly heavier gloss finish. Is there a trick that I haven't yet discovered? ... I've even heard of some amateur painters try wetting the surface before applying the gloss touch ups? .. Hmm??? --------------------------------------------------------------------------------------- My current approach .. Installed pre primed/semi glossed 1x3 baseboards and quarter round mounted above it (gives a 2-3mm mitred look) to the finished baseboards. Countersunk all nail heads and filled with Elmer's white wood filler. Sanded with 200 grit then wet/dry sand paper, then applied touch ups with KILZ white primer. --------------------------------------------------------------------------------------- So, now facing the semi gloss finishing touch ups, which pretty much takes me back to my original question above. Anyway, keen to hear feedback on this from more seasoned painters than myself! All the best, Cal :)