Kinetic aspects on ferric arsenate formation in a fix bed gas-solid reaction system

The fixation of arsenic contained in gases produced during pyrometallurgical processes by using solid ferric oxide was studied in the range 873-1073 K under different oxygen potential and solid aggregates porosities. Arsenic fixation on solid iron oxides is described by the pore blocking model under...

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Autores:
Balladares, Eduardo
Parra, Roberto
Sánchez, Mario
Tipo de recurso:
Article of journal
Fecha de publicación:
2015
Institución:
Universidad Nacional de Colombia
Repositorio:
Universidad Nacional de Colombia
Idioma:
spa
OAI Identifier:
oai:repositorio.unal.edu.co:unal/60768
Acceso en línea:
https://repositorio.unal.edu.co/handle/unal/60768
http://bdigital.unal.edu.co/59100/
Palabra clave:
62 Ingeniería y operaciones afines / Engineering
arsenic fixation
flue dust
gas treatment
copper smelting.
Rights
openAccess
License
Atribución-NoComercial 4.0 Internacional
Description
Summary:The fixation of arsenic contained in gases produced during pyrometallurgical processes by using solid ferric oxide was studied in the range 873-1073 K under different oxygen potential and solid aggregates porosities. Arsenic fixation on solid iron oxides is described by the pore blocking model under the studied conditions. The solid product of the reaction has a molar volume 3 times larger than the solid reactant causing fast decreasing of the inter-granular spacing. The activation energies of arsenic fixation reaction are 34.96 and 35.46 kJ/mol for porosities of 0.88 and 0.74 respectively, and for porosity of 0.55 the activation energy was 26.88 kJ/mol. These values of activation energy show that intra-pellets diffusion has an effect only in samples with 0.55 porosity. Minor sintering of particles was detected. Industrial application of the concept demands a reaction system, which in is required better gas-solid contact for attaining larger conversions.