Synthesis of cements from rice hull ash using microwave oven

• Grant number: 07/02820-4
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2008
• End date: December 31, 2009
• Field of knowledge: Engineering - Civil Engineering - Construction Industry
• Principal Investigator: Flávio Aparecido Rodrigues
• Grantee: Flávio Aparecido Rodrigues
• Host Institution: Pró-Reitoria de Pesquisa, Pós-Graduação e Extensão e Assuntos Comunitários. Universidade de Mogi das Cruzes (UMC). Mogi das Cruzes , SP, Brazil

Abstract

The major components of Portland cement are two calcium silicates: Ca3SiO5 and beta-Ca2SiO4. Tricalcium silicate accounts for about 40% of Portland mass while dicalcium silicate represents 20%. Rich-belite cements are hydraulic materials, where the concentration of beta-Ca2SiO4 is higher than conventional cement. It shows a growing interest due to the saving of energy and raw-materials. On the other hand, rice hull ash is an agricultural residue, very abundant in Brazil. This material contains about 15% of silica as constituent. Controlled burning of this material renders very reactive silica. In earlier works, it was demonstrated that silica, derived from rice hull, can be used to prepare beta-Ca2SiO4. In that case, using solid-state chemical reactions, this material could be prepared at 800°C. This project deals with the synthesis of beta-Ca2SiO4 using commercial microwave oven furnace, in substitution to solid-state chemical reaction. Preliminary results show that the synthesis is possible and present great potential to be used as a synthetic method. It can reduce substantially the costs and energy requirement for cement preparation. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ROMANO, JONATAS S.; MIRANDA, MARIANE S.; OLIVEIRA, MEIRI B. R.; RODRIGUES, FLAVIO A.. Biogenic cements and encapsulation of zinc. JOURNAL OF CLEANER PRODUCTION, v. 19, n. 11, p. 1224-1228, JUL 2011. (05/01361-0, 07/02820-4)