| Texto completo | |
| Autor(es): |
Arce, Gretta L. A. F.
;
Neto, Turibio G. Soares
;
Avila, I.
;
Luna, Carlos M. R.
;
Carvalho, Jr., Joao A.
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF CLEANER PRODUCTION; v. 141, p. 1324-1336, JAN 10 2017. |
| Citações Web of Science: | 11 |
| Resumo | |
This study investigated the leaching process in order to maximize Mg and Fe extraction and to produce amorphous silica (SiO2) with high purity. For this, a mining waste identified as S-GO was employed; which is a serpentinite rock with high lizardite 1T and native brucite contents. A Taguchi Experiment Design was used in order to assess the parameters that influence the leaching process such as: granulometry, hydrochloric acid concentration (HCI), leaching temperature, and mass/volume ratio. Furthermore, thermogravimetric analysis (TGA) was done to understand the interrelation between the mineral structure and leaching performance. Results show that lizardite 1T-bearing serpentinite presents a low content of tetrahedral Al3+ and high octahedral Fe3+ contents on S-GO. Native brucite delayed the formation of a hydrated silica layer and improved dissolution of serpentines. For this, Mg and Fe extractions are efficient, reaching 88 2% of Mg and Fe extracted during the first 30 min of reaction, under mild process conditions: stoichiometric mass/volume ratio, 1M HCI concentration, pressure of 1 bar, temperature of 100 degrees C, and 300 gm particle size. On the other hand, an excess of acid improves Mg and Fe extraction by only 10 5% for S-GO. Such characteristics reduce energetic penalties and costs involved on indirect mineral carbonation processes by the pH swing method. (C) 2016 Elsevier Ltd. All rights reserved. (AU) | |
| Processo FAPESP: | 13/21244-5 - ESTUDO EXPERIMENTAL DO SEQUESTRO MINERAL DE CO2 POR PROCESSOS DE BALANÇO DO pH |
| Beneficiário: | Gretta Larisa Aurora Arce Ferrufino |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |