Sodium aluminium phosphate (NaAlPO?) is a compound with several applications, mainly in the fields of ceramics, water treatment, and food processing. Here are some of its key uses:

1. Ceramics and Glass Industry: Sodium aluminium phosphate is used as a fluxing agent in the manufacture of ceramics and glass. It helps to lower the melting point of materials, facilitating the production process.

2. Water Treatment: It is used in water treatment to remove impurities, especially in processes like coagulation and flocculation, where it helps in binding or neutralizing contaminants.

3. Food Additive: Sodium aluminium phosphate can be used as a food additive (E541), mainly in the food industry as an emulsifier and stabilizer. It is commonly used in processed cheeses, baked goods, and other products to maintain texture and prevent separation.

4. Catalysis: In certain chemical reactions, sodium aluminium phosphate may be used as a catalyst or catalyst support due to its ability to interact with various molecules.

5. Fertilizers: It has been explored in agricultural chemistry, particularly in the production of slow-release fertilizers, as it can influence the availability of phosphate in soils over time.

These applications take advantage of its chemical properties, such as its ability to form stable complexes and its phosphate content. However, its use in food products is a subject of scrutiny due to concerns over the presence of aluminum in food additives.