Mine are plaster and the best thing that worked was to soak the glue on the wall with hot soapy water.
Remove plastic tile glue from wall.
You can try sanding with 100 grit sandpaper or you can use klean strip adhesive remover but neither of these methods is guaranteed to easily produce satisfactory results.
It scraped off pretty easy after it softened up in 10 15 minutes.
The heat will soften the adhesive.
If any adhesive gets stuck to the brush remove it by hand and continue until no more adhesive remains on the wall.
If you want to get rid of it you might be considering removing the tile.
A good option to address the old plastic wall tile is to cover it with decorative panels.
How to remove plastic tile glue grout.
The adhesive that was used in a lot of these installations is very tough and you might even find that it is still not completely cured behind the tile.
Since not all will come off there will be an uneven layer of adhesive left behind.
Just answered your thread about repairing walls after removing wallpaper but i would recommend a completely different approach for the walls in this photo.
Apply an adhesive removing paste to the wall.
Look for a formula that is either made for ceramic tile.
You will then have to pry off the leftover residue.
How to remove ceramic tile glue from a wall.
Irrespective of the adhesive formula you have to cover the floor with old cloths as to protect it from the residues which will fall off the wall.
Step 3 wipe some tile adhesive remover over the surface of the wall.
That probably isn t the best idea.
Press the tip of the scraper at a joint in the tiles.
Wait several minutes and use a large scrapper to remove the mastic.
If the adhesive is not cement based you could try sprinkling water to the wall to ease the scrapping process.
Lower the handle of the scraper to a 45 degree angle and push down to drive the scraper s.
This can be accomplished using a pry bar to peel off the larger chunks.
Apply some water to a small section of the adhesive.
If the adhesive used was organic mastic the water will begin to soften it allowing you to.