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Relevance of Colloid Inherent Salt Estimated by Surface Complexation Modeling of Surface Charge Densities for Different Silica Colloids. COLLOIDS AND INTERFACES 2022. [DOI: 10.3390/colloids6020023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Potentiometric titrations have been routinely used to measure the proton-related surface charge density (SCD) of particles in solution. Here, we quantify the SCD of silica nanoparticles (NPs) that are commercially available as charge-stabilized colloids (by the addition of NaOH) in the presence of known amounts of added NaCl. The experimental results are simulated by surface complexation models (SCMs) of the electrical double layer (EDL). The modeling results suggest that involving only the added NaCl electrolyte yields poor agreement between the experiment and the best achievable fit. An increase in the Na concentration accounting for the colloid inherent salt (CIS) associated with these charge-stabilized colloids results in much better simulations. In the available literature, this CIS has often been disregarded. However, in the modeling, the total concentration of Na must be known for a consistent mole balance and derivation of reliable ion-pair binding constants. If the CIS is not accounted for or the original suspensions are not dialyzed, the presence of CIS renders the study of those colloids difficult, particularly when investigating specific ion effects, since the CIS always interferes. In the present work, we show that the SCM-estimated amount of CIS from varying the total salt and solid concentration agrees surprisingly well with the manufacturer specification.
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Roa R, Menne D, Riest J, Buzatu P, Zholkovskiy EK, Dhont JKG, Wessling M, Nägele G. Ultrafiltration of charge-stabilized dispersions at low salinity. SOFT MATTER 2016; 12:4638-4653. [PMID: 27113088 DOI: 10.1039/c6sm00660d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present a comprehensive study of cross-flow ultrafiltration (UF) of charge-stabilized suspensions, under low-salinity conditions of electrostatically strongly repelling colloidal particles. The axially varying permeate flux, near-membrane concentration-polarization (CP) layer and osmotic pressure profiles are calculated using a macroscopic diffusion-advection boundary layer method, and are compared with filtration experiments on aqueous suspensions of charge-stabilized silica particles. The theoretical description based on the one-component macroion fluid model (OCM) accounts for the strong influence of surface-released counterions on the renormalized colloid charge and suspension osmotic compressibility, and for the influence of the colloidal hydrodynamic interactions and electric double layer repulsion on the concentration-dependent suspension viscosity η, and collective diffusion coefficient Dc. A strong electro-hydrodynamic enhancement of Dc and η, and likewise of the osmotic pressure, is predicted theoretically, as compared with their values for a hard-sphere suspension. We also point to the failure of generalized Stokes-Einstein relations describing reciprocal relations between Dc and η. According to our filtration model, Dc is of dominant influence, giving rise to an only weakly developed CP layer having practically no effect on the permeate flux. This prediction is quantitatively confirmed by our UF measurements of the permeate flux using an aqueous suspension of charged silica spheres as the feed system. The experimentally detected fouling for the largest considered transmembrane pressure values is shown not to be due to filter cake formation by crystallization or vitrification.
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Affiliation(s)
- Rafael Roa
- Forschungszentrum Jülich, Institute of Complex Systems (ICS-3), 52425 Jülich, Germany. and Helmholtz-Zentrum Berlin, Soft Matter and Functional Materials, 14109 Berlin, Germany
| | - Daniel Menne
- RWTH Aachen University, Chemical Process Engineering, 52064 Aachen, Germany
| | - Jonas Riest
- Forschungszentrum Jülich, Institute of Complex Systems (ICS-3), 52425 Jülich, Germany. and Jülich-Aachen Research Alliance, JARA-Soft Matter
| | - Pompilia Buzatu
- RWTH Aachen University, Chemical Process Engineering, 52064 Aachen, Germany and DWI Leibniz Institute for Interactive Materials, 52074 Aachen, Germany
| | - Emiliy K Zholkovskiy
- Ukrainian Academy of Sciences, Institute of Bio-Colloid Chemistry, 03142 Kiev, Ukraine
| | - Jan K G Dhont
- Forschungszentrum Jülich, Institute of Complex Systems (ICS-3), 52425 Jülich, Germany. and Jülich-Aachen Research Alliance, JARA-Soft Matter, and Physics Department, Heinrich-Heine Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Matthias Wessling
- RWTH Aachen University, Chemical Process Engineering, 52064 Aachen, Germany and Jülich-Aachen Research Alliance, JARA-Soft Matter, and DWI Leibniz Institute for Interactive Materials, 52074 Aachen, Germany
| | - Gerhard Nägele
- Forschungszentrum Jülich, Institute of Complex Systems (ICS-3), 52425 Jülich, Germany. and Jülich-Aachen Research Alliance, JARA-Soft Matter, and Physics Department, Heinrich-Heine Universität Düsseldorf, 40225 Düsseldorf, Germany
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van der Linden M, Conchúir BO, Spigone E, Niranjan A, Zaccone A, Cicuta P. Microscopic Origin of the Hofmeister Effect in Gelation Kinetics of Colloidal Silica. J Phys Chem Lett 2015; 6:2881-2887. [PMID: 26267174 DOI: 10.1021/acs.jpclett.5b01300] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The gelation kinetics of silica nanoparticles is a central process in physical chemistry, yet it is not fully understood. Gelation times are measured to increase by over 4 orders of magnitude, simply changing the monovalent salt species from CsCl to LiCl. This striking effect has no microscopic explanation within current paradigms. The trend is consistent with the Hofmeister series, pointing to short-ranged solvation effects not included in the standard colloidal (DLVO) interaction potential. By implementing a simple form for short-range repulsion within a model that relates the gelation timescale to the colloidal interaction forces, we are able to explain the many orders of magnitude difference in the gelation times at fixed salt concentration. The model allows us to estimate the magnitude of the non-DLVO hydration forces, which dominate the interparticle interactions on the length scale of the hydrated ion diameter. This opens the possibility of finely tuning the gelation time scale of nanoparticles by just adjusting the background electrolyte species.
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Affiliation(s)
- Marte van der Linden
- †Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, United Kingdom
| | - Breanndán O Conchúir
- †Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, United Kingdom
| | - Elisabetta Spigone
- †Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, United Kingdom
| | - Arun Niranjan
- †Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, United Kingdom
| | - Alessio Zaccone
- †Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, United Kingdom
- ‡Physics Department and Institute for Advanced Study, Technische Universität München, Lichtenbergstrasse 2 a, Garching 85748, Germany
| | - Pietro Cicuta
- †Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, United Kingdom
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Sim S, Taheri A, Chong T, Krantz W, Fane A. Colloidal metastability and membrane fouling – Effects of crossflow velocity, flux, salinity and colloid concentration. J Memb Sci 2014. [DOI: 10.1016/j.memsci.2014.06.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sim S, Chong T, Krantz W, Fane A. Monitoring of colloidal fouling and its associated metastability using Ultrasonic Time Domain Reflectometry. J Memb Sci 2012. [DOI: 10.1016/j.memsci.2012.02.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Trompette J, Arurault L, Fontorbes S, Massot L. Influence of the anion specificity on the electrochemical corrosion of anodized aluminum substrates. Electrochim Acta 2010. [DOI: 10.1016/j.electacta.2009.12.063] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Castelletto V, Hamley IW, Clifton LA, Green RJ. Osmotic pressure and aggregate shape in BSA/poly(ethylene glycol)-lipid/Dextran solutions. Biophys Chem 2008; 134:34-8. [DOI: 10.1016/j.bpc.2008.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 01/07/2008] [Accepted: 01/08/2008] [Indexed: 11/26/2022]
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Trompette JL, Vergnes H. Influence of Base Electrolytes on the Electrodeposition of Iron onto a Silicon Surface. J Phys Chem B 2006; 110:14779-86. [PMID: 16869586 DOI: 10.1021/jp061614e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Comparative electrodeposition of iron onto the surface of silicon was investigated at large overpotential in the presence of some base electrolytes. The nanostructure of the iron electrodeposits was analyzed with SEM and FE-SEM measurements. The results highlight the influences of ion specificity on the rate of hydrogen evolution and of selective ion adsorption on the morphology of the iron electrodeposits.
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Affiliation(s)
- J L Trompette
- Laboratoire de Génie Chimique UMR 5503, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex, France.
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