Process for preparing sodium dichromate

TLDR: In this paper, a process for producing the sodium dichromate through a carbonization method comprising of converting the sodium chromate into the mixture via carbon dioxide under a pressurizing condition, delivering the mixture to a tower after a cascade reaction of more than three continuous towers.

Abstract: The invention provides a process for preparing sodium dichromate, namely producing the sodium dichromate through a carbonization method comprising: converting sodium chromate into the sodium dichromate via carbon dioxide under pressurizing condition; delivering sodium chromate neutral liquor with impurities removed to a carbonization tower after a cascade reaction of more than three continuous towers; obtaining carbonizing liquor by controlling different gradient parameters (concentration and temperature of the carbonizing liquor, partial pressure of the carbon dioxide, carbonizing time and the like), continuously carbonizing and separating under pressure; obtaining sodium dichromate finished products through concentrating, filtering, evaporating, crystallizing and centrifugal dehydrating.