Natural stone is permeable and breathable, soaking in rain water will cause water spots and cannot be dried naturally. Iron molecules in the stone will appear yellow rust stains if they are soaked in water for a long time. So, how to deal with rust spots on natural stone? Let's take a look with Jiahao editor.
1. When dealing with rust spots on the surface, just brush the surface with a rust remover. Sometimes, the surface grinding and polishing method can also be used for treatment; the treatment of deep rust spots is relatively more complicated, and a certain dosage and reaction time need to be maintained. Sometimes it needs to be reused to achieve the desired effect.
2. After the stone is constructed with a rust remover, it is recommended to clean it with water again. After drying, be sure to use a high-quality stone curing agent for protection. The purpose is to completely remove the residue after the oxidation reaction and prevent the oxidation reaction from happening again.
3. Try to avoid using oxalic acid to directly clean the stone rust spots, because oxalic acid simply redoxes the rust spots (Fe3+), and the redox iron ions (Fe2+) are unstable and easy to re-oxidize with water and oxygen in the air. The reaction regenerates rust, and will further expand the area of rust spots along with the flow of the oxalic acid aqueous solution. This is why when oxalic acid is used to remove rust, the more rust spots will be removed, and the larger the removal.
4. When choosing rust remover, be sure to choose good quality products. Because a good rust remover is not only an acid component, but also an appropriate amount of additives to maintain the stability of iron ions in the redox reaction. The rust spots treated with this rust remover can be kept for a long time without recurrence even if they are not protected. On the contrary, some rust removers are just simple mixtures of some acids, which cannot maintain the stability of iron ions in the oxidation-reduction reaction and have high recurrence.
5. Due to the different composition of marble and granite, their properties are different. The main component of marble is calcium carbonate, which is alkaline; the main component of granite is silica, which is acidic. Therefore, when using rust remover, we must distinguish between marble rust remover and granite rust remover. Granite rust remover must not be used for rust stain treatment of marble.