Behavior of Chromate Ions in CaO-Al₂(SO₄)₃ Suspension

by Open Science Repository Chemistry
(March 2013)

Abstract

Behavior of the chromate ions and their removal efficiency in CaO-Al₂(SO₄)₃ suspensions with molar ratio 5:1 was studied. The suspension was prepared by agitating with a magnetic stirrer for constant 3 hours at room temperature. Run products were collected by filtration, washing and air-dry and evaluated by XRD, SEM and DTA. According to XRD and SEM results the major product in this suspension was ettringite with minor amounts of gypsum and calcite. DTA results showed that the presence of the chromate ions in the suspension retards the formation of the products and decreases the degree of their crystallinity. However, there is high removal of the chromate ions by the formed suspension products. This is related to the substitution of the chromate ions by sulfate in the ettringite crystals.

Keywords: CaO-Al₂(SO₄)₃, suspensions, chromate ions, removal.

Full text

doi: 10.7392/Chemistry.70081936.