Systematic evaluation of amorphous silica production from rice husk ashes

Autor(es)

Santana Costa, Jose Arnaldo ^[1] ; Paranhos, Caio Marcio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Chem, Polymer Lab, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF CLEANER PRODUCTION; v. 192, p. 688-697, AUG 10 2018.
• Citações Web of Science: 24

Resumo

Amorphous silica (SiO2) was extracted from the rice husk ashes (RHAs) of the agulhinha and cateto varieties. Optimized time, temperature, extractor concentration, and reaction time for a sustainable and cleaner production of SiO2 from RHAs were studied. Textural and internal structures were analyzed by N-2 adsorption-desorption isotherms. The percentage of SiO2 in the treated rice husks (RHs) increased by approximately 11 and 12% for the agulhinha and cateto varieties, respectively. The silica present in the RHAs remained predominantly amorphous for all of the times and temperatures investigated. The optimum parameters for calcination of the RHs were: 2 hat 700 degrees C. Type IV isotherms with type H1 hysteresis and good specific surface area values were observed. The optimum parameters for extraction of the amorphous silica were: concentration of 4 mol L-1 NaOH and 4 h of reaction. The extraction yield values were 80-99% and 83-97% for the agulhinha and cateto RHAs, respectively. (C) 2018 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 14/05679-4 - Desenvolvimento de materiais mesoporosos baseados em sílica oriunda de biomassa para utilização como sistema remediador de hidrocarbonetos policíclicos aromáticos (HPAs)
• Beneficiário: José Arnaldo Santana Costa
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs