Influence of porosity and relative humidity on consolidation of dolostone with calcium hydroxide nanoparticles: Effectiveness assessment with non-destructive techniques

Journal Article · Mon Feb 15 00:00:00 EST 2010 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2009.11.007· OSTI ID:22066178

Lopez-Arce, P ^[1]; Gomez-Villalba, L S ^[1]; Pinho, L ^[2]; Fernandez-Valle, M E ^[3]; Alvarez de Buergo, M; Fort, R ^[1]

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1. Group of Applied Petrology to Heritage Conservation, Institute of Economic Geology (CSIC-UCM), Madrid 28040 (Spain)
2. Center of Construction Studies, Engineering Faculty, Oporto University, Oporto 4200-465 (Portugal)
3. Research Assistance Center, Nuclear Magnetic Resonance (Pluridisciplinar Institute), Complutense University of Madrid (UCM), Madrid 28040 (Spain)

Slaked lime (Ca(OH){sub 2}) nanoparticles were exposed at 33% and 75% relative humidity (RH) to consolidate dolostone samples used in historical buildings. Non-destructive techniques (NDT) were applied to determine the chemical, morphological, physical and hydric properties of the stone samples, before and after 20 days treatment. Morphological and mineralogical characterisation of the nanoparticles was performed. 75% RH favors the consolidation process studied under Environmental Scanning Electron Microscopy (ESEM-EDS), spectrophotometry, capillarity, water absorption under vacuum, ultrasound velocity, Nuclear Magnetic Resonance (imaging and relaxometry) and Optical Surface Roughness analyses. At 75% RH the nanoparticles fill the pores and inter-crystalline dolomite grain contacts but do not favor calcite re-crystallization as it occurs at 33% RH. The ESEM, XRD and TEM analyses under 75% RH reveal the fast transformation of portlandite (Ca(OH){sub 2}) into vaterite (CaCO{sub 3}), monohydrocalcite (CaCO{sub 3} . H{sub 2}O) and calcite (CaCO{sub 3}), and eventually the physical and hydric properties of the stones significantly improve. New insights are provided for the assessment of consolidation effectiveness of porous carbonate stones with calcium hydroxide nanoparticles under optimum RH conditions combining several NDT.

• OSTI ID: 22066178
• Journal Information: Materials Characterization, Vol. 61, Issue 2; Other Information: Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
CALCITE
CALCIUM CARBONATES
CALCIUM HYDROXIDES
DOLOMITE
HUMIDITY
NANOSTRUCTURES
NUCLEAR MAGNETIC RESONANCE
PARTICLES
POROSITY
POROUS MATERIALS
RECRYSTALLIZATION
ROUGHNESS
SCANNING ELECTRON MICROSCOPY
SPECTROPHOTOMETRY
SURFACES
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION