HOW TO REMOVE THE GROUT FROM PORPHYRY FLOOR TILES?
What can I use to remove the adhesive used for the stone tiling from the porphyry floor on my porch?
Considering that the adhesives used are usually based on cement, I recommend using a liquid buffering acid from Mapei, Keranet for cleaning, which are usually only found in construction stores. When used without being diluted and leaving it to work for a few minutes – possibly without which the product could damage the porphyry cement grout – and then working with a stiff plastic brush, the residues should disappear; then rinse thoroughly.
If the problem is not resolved you must be careful (mask and gloves, to always be used with keranet) and use caustic soda which in desperate cases should solve the problem.
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