Sodium aluminates obtained from the (NO3)3 • 9H2O - NaOH system using the controlled precipitation method

• Published in: Ingeniería e investigación Vol. 30; no. 2; pp. 16 - 24
• Main Authors: Ruiz Madroñero, Christhy Vanessa, Rodríguez Páez, Jorge Enrique
• Format: Journal Article
• Language: English
• Published: 01.05.2010
• ISSN: 0120-5609; 2248-8723
• DOI: 10.15446/ing.investig.v30n2.15726

Sodium aluminate, NaAlO2• xH2O, is an important commercial chemical used in water treatment, as a source of aluminium in the preparation of zeolites and other catalytic materials and as an additive in paper manufacturing. Sodium aluminates were synthesised in this work by using the Al(NO3)3 • 9H2O- NaOH system's controlled precipitation method. Using the controlled precipitation method enabled identifying the process's different stages from potentiometric titration of Al(NO3)3 • 9H2O dissolved in water and using NaOH as precipitating agent to ensure control and reproducibility and also identify final product characteristics. Powders were characterised by infrared spectroscopy (FTIR), X-ray diffraction (XRD) and gravimetric and differential thermal analysis (GDTA). The results indicated that NaAlO2 crystallised well at 1,000°C (obtained as the main crystalline sodium aluminate phase) and that β-alumina treatment began to form at 1,500°C.