Estudo comparativo entre sílica obtida por lixívia ácida da casca de arroz e sílica obtida por tratamento térmico da cinza de casca de arroz

A comparison between silica by acid leaching of rice husk (RH) and silica obtained from thermal treatment of rice husk ash (RHA) is presented. The best leaching results were obtained using 10% hydrochloric acid followed by washing with water. The alternative method, calcination of RHA at 700 ºC for...

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Bibliographic Details
Main Authors: Viviana Possamai Della, Dachamir Hotza, Janaína Accordi Junkes, Antonio Pedro Novaes de Oliveira
Format: Article
Language:English
Published: Sociedade Brasileira de Química 2006-12-01
Series:Química Nova
Subjects:
Online Access:http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422006000600005&lng=en&tlng=en
Description
Summary:A comparison between silica by acid leaching of rice husk (RH) and silica obtained from thermal treatment of rice husk ash (RHA) is presented. The best leaching results were obtained using 10% hydrochloric acid followed by washing with water. The alternative method, calcination of RHA at 700 ºC for 6 h followed by grinding for 80 min, was more effective. Silica obtained from RH was about 97% amorphous, had a 17.37 µm mean particle size, and a specific surface area of 296 m²/g. On the other hand, for silica obtained from RHA the values were about 95% amorphous material 0.68 µm, and 81 m²/g.
ISSN:1678-7064