Process and plant for thermal decomposition of aluminium chloride hydrate into aluminium oxide

Abstract

A process and its relating plant for thermal conversion of aluminum chloride hydrate into aluminum oxide and gaseous hydrogen chloride. In a first step, aluminum chloride hydrate is fed into a decomposition reactor where it is heated to a temperature between 120 and 400° C. Afterwards, the partially decomposed aluminum chloride hydrate is finally calcined to aluminum oxide at a temperature between 850 and 1200° C. in a second reactor. The aluminum chloride hydrate is admixed with aluminum oxide in an intensive mixer with a mass ratio between 1:1 and 10:1 aluminum chloride hydrate to aluminum oxide for using a fluidized bed reactor as a decomposition reactor.

1 .- 16 . (canceled) 
     
     
         17 . A plant for thermal conversion of aluminum chloride hydrate into aluminum oxide and gaseous hydrogen chloride comprising a decomposition reactor for decomposing the aluminum chloride hydrate and a calcination reactor for calcining the partially decomposed aluminum chloride hydrate to aluminum oxide, characterized by a mixer with knifes and/or ploughshares and/or paddles, wherein the aluminum chloride hydrate is mixed with aluminum oxide and that the decomposition reactor is a fluidized bed reactor. 
     
     
         18 . The plant according to  claim 17 , wherein the decomposition reactor is designed such that it is able to heat the material to a first temperature while the calcination reactor is designed to heat the material to a second temperature being higher than the first temperature.