Methanol Leaching of Reaction Product of Chromite with Molten Sodium Salts

Abstract

Free sodium hydroxide and sodium chromate was separated from the reaction product of chromite with molten sodium salts by the two-step leaching with methanol and water.
In the first step, the reaction product was leached with methanol. About 90% of free sodium hydroxide was selectively dissolved in methanol under the following optimum conditions; weight ratio of 90% methanol solution to the reaction product: 4.0, leaching temperature: 35° C, leaching time: 1 hr.
In the second step, the leached residue was leached with water. Whole sodium chromate was dissolved in water.
On the basis of experimental results, a process for the production of sodium chromate from chromite was proposed.