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Falzone G, Mehdipour I, Neithalath N, Bauchy M, Simonetti D, Sant G. New insights into the mechanisms of carbon dioxide mineralization by portlandite. AIChE J 2021. [DOI: 10.1002/aic.17160] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gabriel Falzone
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering University of California Los Angeles California USA
- Institute for Carbon Management (ICM) University of California Los Angeles California USA
| | - Iman Mehdipour
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering University of California Los Angeles California USA
- Institute for Carbon Management (ICM) University of California Los Angeles California USA
| | - Narayanan Neithalath
- School of Sustainable Engineering and the Built‐Environment Arizona State University Tempe Arizona USA
| | - Mathieu Bauchy
- Institute for Carbon Management (ICM) University of California Los Angeles California USA
- Laboratory for the Physics of Amorphous and Inorganic Solids (PARISlab), Department of Civil and Environmental Engineering University of California Los Angeles California USA
| | - Dante Simonetti
- Institute for Carbon Management (ICM) University of California Los Angeles California USA
- Department of Chemical and Biomolecular Engineering University of California Los Angeles California USA
| | - Gaurav Sant
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering University of California Los Angeles California USA
- Institute for Carbon Management (ICM) University of California Los Angeles California USA
- Department of Materials Science and Engineering University of California Los Angeles California USA
- California Nanosystems Institute (CNSI) University of California Los Angeles California USA
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Mehdipour I, Falzone G, Prentice D, Neithalath N, Simonetti D, Sant G. The role of gas flow distributions on CO2 mineralization within monolithic cemented composites: coupled CFD-factorial design approach. REACT CHEM ENG 2021. [DOI: 10.1039/d0re00433b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Optimizing the spatial distribution of contacting gas and the gas processing conditions enhances CO2 mineralization reactions and material properties of carbonate-cementitious monoliths.
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Affiliation(s)
- Iman Mehdipour
- Laboratory for the Chemistry of Construction Materials (LC2)
- Department of Civil and Environmental Engineering
- University of California
- Los Angeles
- USA
| | - Gabriel Falzone
- Laboratory for the Chemistry of Construction Materials (LC2)
- Department of Civil and Environmental Engineering
- University of California
- Los Angeles
- USA
| | - Dale Prentice
- Laboratory for the Chemistry of Construction Materials (LC2)
- Department of Civil and Environmental Engineering
- University of California
- Los Angeles
- USA
| | - Narayanan Neithalath
- School of Sustainable Engineering and the Built Environment
- Arizona State University
- Tempe
- USA
| | - Dante Simonetti
- Institute for Carbon Management (ICM)
- University of California
- Los Angeles
- USA
- Department of Chemical and Biomolecular Engineering
| | - Gaurav Sant
- Laboratory for the Chemistry of Construction Materials (LC2)
- Department of Civil and Environmental Engineering
- University of California
- Los Angeles
- USA
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Bhagavathi Kandy S, Mehdipour I, Neithalath N, Bauchy M, Garboczi E, Srivastava S, Gaedt T, Sant G. Temperature-Induced Aggregation in Portlandite Suspensions. Langmuir 2020; 36:10811-10821. [PMID: 32799535 DOI: 10.1021/acs.langmuir.0c01798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Temperature is well known to affect the aggregation behavior of colloidal suspensions. This paper elucidates the temperature dependence of the rheology of portlandite (calcium hydroxide: Ca(OH)2) suspensions that feature a high ionic strength and a pH close to the particle's isoelectric point. In contrast to the viscosity of the suspending medium (saturated solution of Ca(OH)2 in water), the viscosity of Ca(OH)2 suspensions is found to increase with elevating temperature. This behavior is shown to arise from the temperature-induced aggregation of polydisperse Ca(OH)2 particulates because of the diminution of electrostatic repulsive forces with increasing temperature. The temperature dependence of the suspension viscosity is further shown to diminish with increasing particle volume fraction as a result of volumetric crowding and the formation of denser fractal structures in the suspension. Significantly, the temperature-dependent rheological response of suspensions is shown to be strongly affected by the suspending medium's properties, including ionic strength and ion valence, which affect aggregation kinetics. These outcomes provide new insights into aggregation processes that affect the temperature-dependent rheology of portlandite-based and similar suspensions that feature strong charge screening behavior.
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Affiliation(s)
- Sharu Bhagavathi Kandy
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, United States
- Institute for Carbon Management (ICM), University of California, Los Angeles, California 90095, United States
| | - Iman Mehdipour
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, United States
- Institute for Carbon Management (ICM), University of California, Los Angeles, California 90095, United States
| | - Narayanan Neithalath
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona 86587, United States
| | - Mathieu Bauchy
- Institute for Carbon Management (ICM), University of California, Los Angeles, California 90095, United States
- Laboratory for the Physics of AmoRphous and Inorganic Solids (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, United States
| | - Edward Garboczi
- Applied Chemicals and Materials Division, Material Measurement Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305, United States
| | - Samanvaya Srivastava
- Institute for Carbon Management (ICM), University of California, Los Angeles, California 90095, United States
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, California 90095, United States
| | - Torben Gaedt
- Department of Chemistry, Technische Universität München, Lehrstuhl für Bauchemie, Lichtenbergstrasse 4, 85747 Garching , Germany
| | - Gaurav Sant
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, United States
- Institute for Carbon Management (ICM), University of California, Los Angeles, California 90095, United States
- Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, United States
- California Nanosystems Institute (CNSI), University of California, Los Angeles, California 90095, United States
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Mehdipour I, Atahan H, Neithalath N, Bauchy M, Garboczi E, Sant G. How clay particulates affect flow cessation and the coiling stability of yield stress-matched cementing suspensions. Soft Matter 2020; 16:3929-3940. [PMID: 32240280 DOI: 10.1039/c9sm02414j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The remarkable increase in the flow resistance of dense suspensions can hinder 3D-printing processes on account of flow cessation in the extruder, and filament fragility/rupture following deposition. Understanding the nature of rheological changes that occur is critical to manipulate flow conditions or to dose flow modifiers for 3D-printing. Therefore, this paper elucidates the influences of clay particulates on controlling flow cessation and the shape stability of dense cementing suspensions that typically feature poor printability. A rope coiling method was implemented with varying stand-off distances to probe the buckling stability and tendency to fracture of dense suspensions that undergo stretching and bending during deposition. The contributions of flocculation and short-term percolation due to the kinetics of structure formation to deformation rate were deconvoluted using a stepped isostress method. It is shown that the shear stress indicates a divergence with a power-law scaling when the particle volume fraction approaches the jamming limit; φ → φj ≈ φmax. Such a power-law divergence of the shear stress decreases by a factor of 10 with increasing clay dosage. Such behavior in clay-containing suspensions arises from a decrease in the relative packing fraction (φ/φmax) and the formation of fractally-architected aggregates with stronger interparticle interactions, whose uniform arrangement controls flow cessation in the extruder and suspension homogeneity, thereby imparting greater buckling stability. The outcomes offer new insights for assessing/improving the extrudability and printability behavior during slurry-based 3D-printing process.
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Affiliation(s)
- Iman Mehdipour
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA.
| | - Hakan Atahan
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA. and Department of Civil Engineering, Istanbul Technical University, Istanbul, Turkey
| | - Narayanan Neithalath
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA
| | - Mathieu Bauchy
- Laboratory for the Physics of Amorphous and Inorganic Solids (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA and Institute for Carbon Management (ICM), University of California, Los Angeles, CA 90095, USA
| | - Edward Garboczi
- Applied Chemicals and Materials Division, Material Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - Gaurav Sant
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA. and Institute for Carbon Management (ICM), University of California, Los Angeles, CA 90095, USA and Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095, USA and California Nanosystems Institute (CNSI), University of California, Los Angeles, CA 90095, USA
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Timmons J, Mehdipour I, Gao S, Atahan H, Neithalath N, Bauchy M, Garboczi E, Srivastava S, Sant G. Dispersing nano- and micro-sized portlandite particulates via electrosteric exclusion at short screening lengths. Soft Matter 2020; 16:3425-3435. [PMID: 32196056 DOI: 10.1039/d0sm00045k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In spite of their high surface charge (zeta potential ζ = +34 mV), aqueous suspensions of portlandite (calcium hydroxide: Ca(OH)2) exhibit a strong tendency to aggregate, and thereby present unstable suspensions. While a variety of commercial dispersants seek to modify the suspension stability and rheology (e.g., yield stress, viscosity), it remains unclear how the performance of electrostatically and/or electrosterically based additives is affected in aqueous environments having either a high ionic strength and/or a pH close to the particle's isoelectric point (IEP). We show that the high native ionic strength (pH ≈ 12.6, IEP: pH ≈ 13) of saturated portlandite suspensions strongly screens electrostatic forces (Debye length: κ-1 = 1.2 nm). As a result, coulombic repulsion alone is insufficient to mitigate particle aggregation and affect rheology. However, a longer-range geometrical particle-particle exclusion that arises from electrosteric hindrance caused by the introduction of comb polyelectrolyte dispersants is very effective at altering the rheological properties and fractal structuring of suspensions. As a result, comb-like dispersants that stretch into the solvent reduce the suspension's yield stress by 5× at similar levels of adsorption as compared to linear dispersants, thus enhancing the critical solid loading (i.e., at which jamming occurs) by 1.4×. Significantly, the behavior of diverse dispersants is found to be inherently related to the thickness of the adsorbed polymer layer on particle surfaces. These outcomes inform the design of dispersants for concentrated suspensions that present strong charge screening behavior.
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Affiliation(s)
- Jason Timmons
- Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095, USA. and Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA
| | - Iman Mehdipour
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA
| | - Shang Gao
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA.
| | - Hakan Atahan
- Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA and Department of Civil Engineering, Istanbul Technical University, Istanbul, Turkey
| | - Narayanan Neithalath
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ 86587, USA
| | - Mathieu Bauchy
- Laboratory for the Physics of Amorphous and Inorganic Solids (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA and Institute for Carbon Management, University of California, Los Angeles, CA 90095, USA
| | - Edward Garboczi
- Applied Chemicals and Materials Division, Material Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - Samanvaya Srivastava
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA. and Institute for Carbon Management, University of California, Los Angeles, CA 90095, USA
| | - Gaurav Sant
- Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095, USA. and Laboratory for the Chemistry of Construction Materials (LC2), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA and Institute for Carbon Management, University of California, Los Angeles, CA 90095, USA and California Nanosystems Institute (CNSI), University of California, Los Angeles, CA 90095, USA
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