Biogenic cements and encapsulation of zinc

Author(s)

Romano, Jonatas S. ^[1] ; Miranda, Mariane S. ^[1] ; Oliveira, Meiri B. R. ^[1] ; Rodrigues, Flavio A. ^[1]

Affiliation

^[1] UMC, NCA, Lab Mat & Superficies LABMAR, BR-08780911 Mogi Das Cruzes, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF CLEANER PRODUCTION; v. 19, n. 11, p. 1224-1228, JUL 2011.
• Web of Science Citations: 5

Abstract

Metals can be stabilized into cement matrix by solidification/stabilization process. Rice hull is an agricultural residue containing about 10-20% (weight) of silica. It can be used to synthesize beta-Ca(2)SiO(4), an important component of Portland cement. Furthermore it is possible to prepare beta-Ca(2)SiO(4) doped with heavy metals. Here we describe the synthesis of beta-Ca(2)SiO(4) doped with zinc and the behavior of mortars prepared using this material. Products were analyzed by X-ray diffraction, differential thermal analysis and scanning electron microscopy coupled to energy-dispersive spectroscopy. The maximum amount of zinc that can be inserted into beta-Ca(2)SiO(4), without affecting the crystalline structure, is limited to 2% (molar basis). In comparison with conventional mortars, zinc-modified mortars show a similar behavior, regarding porosity, resistance to acidic attack and compressive strength. The synthesis of beta-Ca(2)SiO(4) doped with zinc presents a new possibility for safety enhancement in solidification/stabilization processes. (C) 2011 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 05/01361-0 - Study of the reactivity of beta-Ca2SiO4 obtained from rice rull ash
• Grantee: Flávio Aparecido Rodrigues
• Support Opportunities: Regular Research Grants
• FAPESP's process: 07/02820-4 - Synthesis of cements from rice hull ash using microwave oven
• Grantee: Flávio Aparecido Rodrigues
• Support Opportunities: Regular Research Grants