Detailed steps of how to remove yellow rust spots on marble

The natural marble, which is mainly composed of carbonatite, is not acid resistant. The marble turns red mainly because the ferrous sulfate in the stone reacts with oxygen in the air to produce iron oxide, which is red. The yellowing of marble is mainly due to the infiltration of sodium peroxide and sulfur into marble.

There are several kinds of agents used for stone color spots, rust spots and yellow spots on the market:

1. Compound agent of hydrogen peroxide

2. Compound agent of hypochlorous acid

3. Hydrogen sulfuric acid composite agent

4. Inorganic acid composite agent

5. Lime acid compound agent (can only remove surface rust)

Stone cleaning agents include: degreasing agent, degreasing paste, neutral cleaning agent, water spot remover, etc.

Derusting steps:

1、 Stone detection

(1). Check whether the stone absorbs water. If the stone is protected and cannot absorb water, test it with alcohol to see whether it absorbs alcohol. If it does not absorb water and alcohol, the front stone protection has organized most of the material penetration. At this time, you can choose to mail yellow scavengers, such as ointment removers. If the stone can absorb alcohol, you can use water cleaning agents immediately after infiltrating the stone with alcohol.

(2). Build the pH value of detergent. If the pH value is less than 5, test the agent on marble. If there is corrosion, it can not be used for marble derusting

(3). The selected medicament was tested on marble chloasma, and the medicament with reducing and removing effect was selected.

2、 Yellow removal process

After selecting the medicament, apply the absorbent paper towel on the chloasma to be removed, then sprinkle the medicament evenly on the paper towel, tap it gently with a plastic board brush to filter out the bubbles, so that the paper towel full of medicament is tightly applied to the stone surface. Then cover the fresh-keeping film on the paper towel, moisturize for more than half an hour, and let the medicine fully penetrate into the stone. Can come into contact with yellowing substances to produce chemical reactions. After half an hour, uncover the preservative film and dry in the shade until the paper towel is completely dry.

Check the yellowing effect. If it is effective but not ideal, repeat the above yellowing procedures. If it is still not ideal after more than three times, replace it with other agents for test.

3、 Clean water application

There is an important procedure to be completed after reaching the of eliminating yellow eyes; Applying with clean water is to apply multiple layers of paper towels with clean water. The procedure is the same as that of applying the agent. The purpose of this is to remove the residual agent and the dirt after the reaction from the stone.

4、 Do a good job in stone protection

After the above yellow removal work is completed, the work to prevent recurrence has not been completed. The stone after clearing the chloasma shall be completely dried and protected to prevent the stone from yellowing again after absorbing water.