Recovery of vanadium, nickel and magnesium from a fly ash of bitumen-in-water emulsion by chlorination and chemical transport

摘要

Vapor phase extraction of vanadium, nickel and magnesium from a fly ash of Orimulsion(R), a new fuel, has been investigated using high-temperature chlorination with N-2-Cl-2 or air-Cl-2 mixture. The use of N-2-Cl-2 gas was suited for a selective chlorination of metal components. Vanadium and iron were extracted at 400 and 500 degrees C, respectively, as oxychloride or chloride vapors. Mutual separation of nickel and magnesium components was achieved by (i) a selective chlorination followed by vaporization of NiCl2 in the temperature range 650-700 degrees C or (ii) a chemical transport reaction mediated by vapor complexes with Al2Cl6(g) along a modified temperature gradient. During the chlorination, NOx, NH3, SO3 and H2O gases were generated and chlorination schemes were discussed based on the composition of the exhaust gas. (C) 1998 Elsevier Science S.A. [References: 24]