Calcium oxides for CO2 capture obtained from the thermal decomposition of CaCO3 particles coprecipitated with Al3+ ions

被引：16

作者：

Beruto, D. T. ^{[1
,2
]}

Botter, R. ^{[1
,2
]}

Lagazzo, A. ^{[2
]}

Finocchio, E. ^{[2
]}

机构：

[1] Univ Genoa, Res Ctr Mat Sci & Eng, I-16129 Genoa, GE, Italy

[2] Univ Genoa, Dept Chem Engn & Proc, Fac Engn, I-16129 Genoa, Italy

来源：

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY | 2012年 / 32卷 / 02期

关键词：

Limestone decomposition; Sintering; CO2; capture; Al ions; Dilatometer; CAO-BASED SORBENT; FLUIDIZED-BED; CARBONATION; THERMODYNAMICS; CHEMISORPTION; SEQUESTRATION; TEMPERATURE; COMBUSTION; KINETICS; SURFACE;

D O I：

10.1016/j.jeurceramsoc.2011.08.022

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Calcium-carbonate powders were coprecipitated with Al3+ and then decomposed in air and/or under a CO2 flux between 590 degrees C and 1150 degrees C. The data were analysed using a consecutive-decomposition-dilatometer method and the kinetic results were discussed according to the microstructure analysis done by N-2 adsorption isotherms (78 K), SEM and FT-IR measurements. Below 1000 degrees C, CaCO3 particle thermal-decomposition was pseudomorphic, resulting in the formation of a CaO grain porous network. When the CaO grains were formed, the Al3+ diffused among them, producing AlO4 groups that promoted the CaO grain coarsening and reduced O-2(-) surface sites available to CO2 adsorbed molecules to form CO32-. In pure CaO, CO32- diffused through the grain boundary, enhancing Ca2+ and O-2(-) mobility; AlO4 groups reduced CO32- penetration and CaO sintering rate. Above 1000 degrees C, the sintering rate of the doped samples exceeded that of the undoped, likely because of Al3+ diffusion in CaO and viscous flow. (C) 2011 Elsevier Ltd. All rights reserved.

引用

页码：307 / 315

页数：9