I want to buy an air purifier for my bedroom (about 130 square feet, 8ft high) but I'm not sure where I can place it. My bedroom's shape together with my bed and other furnishings means I don't have much open space on the floor to work with. If I put it on the floor then to avoid placing the air purifier directly in my walkway, I would have to shove it into a corner.

I have heard anecdotally that your air purifier should be at least 18 inches away from walls/furniture and ideally near the center of the room. But is that really the case? If so I need to get a smaller purifier that can sit on the corner of my desk, likely a Levoit Core 300 (8.7x8.7 inches) or Winix A231 (9.5x9.5 inches). However, I'd prefer to get a larger, more powerful unit so it can effectively clean the air while on a lower, quieter setting... as long as putting it in a corner won't stifle its performance and defeat the purpose of springing for the bigger model!

I also have a second question, unrelated to the first. I've seen a lot of discussion about VOCs and how the carbon filters in most air purifiers aren't effective at removing them. If that's the case... is there really any reason for me to bother with replacing carbon filters?