Dissolution of serpentine using recyclable ammonium salts for CO 2 mineral carbonation

Autores: Wang, X.|Maroto-Valer, M.M.
Fuente: Fuel
90(3), 1229-1237
2011

Low efficiency of mineral dissolution and unrecyclable use of additives are two barriers for the development of CO2 mineral carbonation. A new pH-swing CO2 mineralisation process using recyclable ammonium salts is proposed to overcome these barriers. This paper presents the studies of mineral dissolution with ammonium salts. In this study, dissolution of a serpentine sample was performed using a series of aqueous solutions, which include (NH4)2SO4, NH4Cl, NH 4HSO4 and H2SO4. NH 4HSO4 is the most efficient in terms of extracting Mg extraction from the serpentine sample. At 100 °C 1.4 M NH 4HSO4 extracted 100% of Mg from serpentine in 3 h, as well as 98% of Fe and 17.6% of Si. The rate limiting mechanism of serpentine dissolution with NH4HSO4 is a chemical reaction with product layer diffusion control and the activation energy of this dissolution was 40.9 kJ mol-1. © 2010 Elsevier Ltd. All rights reserved.