Excellent Perfect Aluminum Sodium Silicate with High Quality

• CAS No.: 1344-00-9
• Color: White
• Appearance: Powder
• Transport Package: Paper
• Specification: large
• Trademark: china
• Origin: China
• HS Code: 2801100000
• Production Capacity: 5000kg/Year

Product Description

In standard Bayer processing, where silicon oxygen and sodium are in abundance, the usual precipitate is sodalite, and it ends up in the red mud where it is disposed of along with the red mud. The benefit of sodalite precipitation is minimizing the risk of silica contamination of the gibbsite precipitate, and enabling recycling of the Bayer liquor, which does not accumulate dissolved silica through repeating cycles. The detriment of sodalite precipitation is major sodium losses from the Bayer liquor, which is a production loss cost. Also there is some aluminum loss from the Bayer liquor as aluminum is a component of sodalite. However, in the presence of calcium, cancrinite, and hydrogarnet, precipitates can form.

All of these silicates consume not just silicon but also aluminum, and therefore represent a production loss in aluminum terms, as well as sodium loss in the case of sodalite and cancrinite. In the case of sodalite, the Na₂O:SiO₂ molar ratio is 2:3. For every mole of silica removed, 0.67 mol of sodium is lost. In the presence of free calcium, cancrinite can form and can reduce sodium loss by as much as 25% compared to the sodalite sodium loss in the absence of calcium, that is, from 8 mol of sodium to 6-Na₆ remains but Na₂X substitutes for 2CaCO₃ (both have an Na₆ component in their chemical formula, cancrinite does not have the Na₂X). However, since cancrinite generally forms only at very high temperatures, over 200°C, and long digestion time periods, conditions which cause quartz dissolution, this defeats the purpose of a cancrinite strategy. Moreover, there is the cost of the lime to offset a rather marginal sodium saving. Thus, the cancrinite strategy is not an attractive option.