1
|
Zhang W, Qi L, Li D, Xiao L. A kinetic model for porosity evaluation in Fe(0) mixed material-based sequential groundwater remediation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168507. [PMID: 37963539 DOI: 10.1016/j.scitotenv.2023.168507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 11/05/2023] [Accepted: 11/09/2023] [Indexed: 11/16/2023]
Abstract
In aquifer systems, particularly those characterized by homogeneity in the shallow layers, the even distribution of contaminants, such as solutes, solvents, and reductive agents or substrates is frequently impeded. Consequently, this complicates the accurate delineation homogeneity within the groundwater matrix, which is a crucial aspect for the effective subsurface treatment of contaminants. In this study, columnar assays were conducted using acid-activated zero-valent iron [Fe(0), ZVI] emulated in situ remediation across disparate iron-to-sand weight ratios. To decipher the interaction between porosity and solute migration, a mass transfer-centric model was developed to provide quantitative insights during heterogeneous groundwater interventions. The results revealed that nitrate attenuation by Fe(0) rigorously adheres to a first-order kinetic paradigm. The efficiency porosity (n̅) during non-equilibrium (rate-limited) conditions can be calculated under different NO3- concentrations and Fe(0)/sand ratios. This analysis predicts that large porosity and preferential flow will occur in the Fe(0)50/% and Fe(0)25/% columns. The optimal parameters were determined as a mixing ratio of Fe(0)/sand of 0.5/0.5 (volume) and an HRT of 7.3 h when the influent NO3--N concentration ranged from 20 mg·L-1 to 100 mg·L-1, resulting in enhanced nitrate removal efficiency. A positive correlation was observed between K (a mass-transfer rate coefficient) and Fe(0)/sand ratio. Using a power-law function to fit A [the value of fitting parameter] and the Fe(0)/sand ratio, a positive correlation was calculated that closely resembles the trend observed in lab columns. This model subsequently facilitated the calibration of operational variables, optimizing the in situ amelioration of nitrate-laden groundwater.
Collapse
Affiliation(s)
- Wen Zhang
- Zhejiang University of Water Resources and Electric Power, No. 508, 2nd Street, Qiantang District, Hangzhou 310018, Zhejiang Province, China; Civil Structural & Environmental Engineering, Trinity College Dublin, The University of Dublin, College Green, Dublin 2 D02 PN40, Ireland
| | - Liang Qi
- Key Laboratory of Coastal Environment and Resources of Zhejiang Province, School of Engineering, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
| | - Dunzhu Li
- Civil Structural & Environmental Engineering, Trinity College Dublin, The University of Dublin, College Green, Dublin 2 D02 PN40, Ireland
| | - Liwen Xiao
- Civil Structural & Environmental Engineering, Trinity College Dublin, The University of Dublin, College Green, Dublin 2 D02 PN40, Ireland.
| |
Collapse
|
2
|
Kim D, Lee H, Yoon H, Oh D, Kim K. Stabilization of high internal phase Pickering emulsions with millimeter-scale droplets using silica particles. SOFT MATTER 2023; 19:3841-3848. [PMID: 37194380 DOI: 10.1039/d3sm00237c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
High internal phase emulsions stabilized with colloidal particles (Pickering HIPEs) have recently been studied intensively because of their great stability achieved by the irreversible adsorption of particles onto the oil-water interface and their usage as a template for synthesizing porous polymeric materials, called PolyHIPEs. In most cases, Pickering HIPEs with microscale droplets ranging from tens of micrometers to hundreds of micrometers have been successfully achieved, but the stabilization of Pickering HIPEs with millimeter-sized droplets is rarely reported. In this study, we report for the first time that, by using shape-anisotropic silica particle aggregates as a stabilizer, successful stabilization of Pickering HIPEs with millimeter-sized droplets can be achieved, and the size of droplets can be simply controlled. Additionally, we demonstrate that stable PolyHIPEs with large pores can be readily converted to PolyHIPEs with millimeter-scale pores, which have advantages in absorbent materials and biomedical engineering applications.
Collapse
Affiliation(s)
- DongGwon Kim
- Department of Chemical and Biomolecular Engineering, Seoul National University of Science and Technology (SeoulTech), Seoul, 01811, Republic of Korea.
| | - HaNeur Lee
- Department of Chemical and Biomolecular Engineering, Seoul National University of Science and Technology (SeoulTech), Seoul, 01811, Republic of Korea.
| | - Hojoon Yoon
- Department of Chemical and Biomolecular Engineering, Seoul National University of Science and Technology (SeoulTech), Seoul, 01811, Republic of Korea.
| | - DongGeun Oh
- Department of Chemical and Biomolecular Engineering, Seoul National University of Science and Technology (SeoulTech), Seoul, 01811, Republic of Korea.
| | - KyuHan Kim
- Department of Chemical and Biomolecular Engineering, Seoul National University of Science and Technology (SeoulTech), Seoul, 01811, Republic of Korea.
| |
Collapse
|
3
|
Zhang Q, Shen X, Chang S, Ou W, Zhang W. Effect of oil properties on the formation and stability of Pickering emulsions stabilized by ultrafine pearl powder. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
4
|
Koroleva MY, Yurtov EV. Ostwald ripening in macro- and nanoemulsions. RUSSIAN CHEMICAL REVIEWS 2021. [DOI: 10.1070/rcr4962] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
5
|
Chen L, Ao F, Ge X, Shen W. Food-Grade Pickering Emulsions: Preparation, Stabilization and Applications. Molecules 2020; 25:E3202. [PMID: 32674301 PMCID: PMC7397194 DOI: 10.3390/molecules25143202] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/10/2020] [Accepted: 07/11/2020] [Indexed: 01/14/2023] Open
Abstract
In recent years, Pickering emulsions have emerged as a new method and have attracted much attention in the fields of food sciences. Unlike conventional emulsions, Pickering emulsions are stabilized by solid particles, which can irreversibly adsorb on the oil-water interface to form a dense film to prevent the aggregation of droplets. The research and development of food-grade solid particles are increasingly favored by scientific researchers. Compared with conventional emulsions, Pickering emulsions have many advantages, such as fewer using amounts of emulsifiers, biocompatibility and higher safety, which may offer feasibility to have broad application prospects in a wide range of fields. In this article, we review the preparation methods, stabilization mechanism, degradation of Pickering emulsions. We also summarize its applications in food sciences in recent years and discuss its future prospects and challenges in this work.
Collapse
Affiliation(s)
- Lijuan Chen
- Department of Food Science and Technology, College of Light Industry Science and Engineering, Nanjing Forestry University, Nanjing 210037, China;
| | - Fen Ao
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi’an 710000, China;
| | - Xuemei Ge
- Department of Food Science and Technology, College of Light Industry Science and Engineering, Nanjing Forestry University, Nanjing 210037, China;
| | - Wen Shen
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi’an 710000, China;
| |
Collapse
|
6
|
Olson MR, Sale TC. Implications of soil mixing for NAPL source zone remediation: Column studies and modeling of field-scale systems. JOURNAL OF CONTAMINANT HYDROLOGY 2015; 177-178:206-219. [PMID: 25981955 DOI: 10.1016/j.jconhyd.2015.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 03/25/2015] [Accepted: 04/26/2015] [Indexed: 06/04/2023]
Abstract
Soil remediation is often inhibited by subsurface heterogeneity, which constrains contaminant/reagent contact. Use of soil mixing techniques for reagent delivery provides a means to overcome contaminant/reagent contact limitations. Furthermore, soil mixing reduces the permeability of treated soils, thus extending the time for reactions to proceed. This paper describes research conducted to evaluate implications of soil mixing on remediation of non-aqueous phase liquid (NAPL) source zones. The research consisted of column studies and subsequent modeling of field-scale systems. For column studies, clean influent water was flushed through columns containing homogenized soils, granular zero valent iron (ZVI), and trichloroethene (TCE) NAPL. Within the columns, NAPL depletion occurred due to dissolution, followed by either column-effluent discharge or ZVI-mediated degradation. Complete removal of TCE NAPL from the columns occurred in 6-8 pore volumes of flow. However, most of the TCE (>96%) was discharged in the column effluent; less than 4% of TCE was degraded. The low fraction of TCE degraded is attributed to the short hydraulic residence time (<4 days) in the columns. Subsequently, modeling was conducted to scale up column results. By scaling up to field-relevant system sizes (>10 m) and reducing permeability by one-or-more orders of magnitude, the residence time could be greatly extended, potentially for periods of years to decades. Model output indicates that the fraction of TCE degraded can be increased to >99.9%, given typical post-mixing soil permeability values. These results suggest that remediation performance can be greatly enhanced by combining contaminant degradation with an extended residence time.
Collapse
Affiliation(s)
- Mitchell R Olson
- Colorado State University, Department of Civil and Environmental Engineering, 1320 Campus Delivery, Fort Collins, CO 80523-1320, United States.
| | - Tom C Sale
- Colorado State University, Department of Civil and Environmental Engineering, 1320 Campus Delivery, Fort Collins, CO 80523-1320, United States
| |
Collapse
|
7
|
Olson MR, Blotevogel J, Borch T, Petersen MA, Royer RA, Sale TC. Long-term potential of in situ chemical reduction for treatment of polychlorinated biphenyls in soils. CHEMOSPHERE 2014; 114:144-149. [PMID: 25113195 DOI: 10.1016/j.chemosphere.2014.03.109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 03/14/2014] [Accepted: 03/30/2014] [Indexed: 06/03/2023]
Abstract
Polychlorinated biphenyls (PCBs) are well-known for being hydrophobic and persistent in the environment. Although many treatment approaches have been demonstrated to result in degradation of PCBs in water or water/cosolvent systems, few examples exist where such approaches have been applied successfully for PCB degradation in soil-water systems. A possible explanation for the limited treatment of PCBs in soil-water systems is that reactants that are capable of degrading PCBs in the aqueous phase are unlikely to persist long enough to achieve meaningful treatment of slowly-desorbing PCBs associated with the soil phase. To investigate this explanation, laboratory studies were conducted to evaluate chemical reductants, including zero valent metals, palladium (Pd) catalyst, and emulsified zero valent iron (EZVI), for dechlorination of PCBs in the presence and absence of soil. In the absence of soil, Pd-catalyzed treatments (Pd with electrolytic ZVI or iron/aluminum alloy) achieved rapid destruction of a model PCB congener, 2-chlorobiphenyl, with half-lives ranging from 43 to 110 min. For treatment of soils containing Aroclor 1248 at an initial concentration of approximately 1,500 mg kg(-1), Pd-catalyzed treatments achieved no measurable enhancement over the background PCB depletion rate (i.e., that measured in the untreated control) of 5.3 mg kg(-1)week(-1). In the presence of soils, EZVI was the only approach evaluated that resulted in a clear enhancement in PCB dechlorination rates. EZVI achieved PCB concentration reductions of greater than 50% at an average rate of 19 mg kg(-1)week(-1). The results suggest that slow PCB desorption limits treatment effectiveness in soils.
Collapse
Affiliation(s)
- Mitchell R Olson
- Colorado State University, Department of Civil and Environmental Engineering, 1320 Campus Delivery, Fort Collins, CO 80523-1320, United States.
| | - J Blotevogel
- Colorado State University, Department of Civil and Environmental Engineering, 1320 Campus Delivery, Fort Collins, CO 80523-1320, United States.
| | - T Borch
- Colorado State University, Department of Soil and Crop Sciences, 1170 Campus Delivery, Fort Collins, CO 80523-1170, United States; Colorado State University, Department of Chemistry, 1872 Campus Delivery, Fort Collins, CO 80523-1872, United States.
| | - M A Petersen
- GE Global Research, One Research Circle, Niskayuna, NY 12309, United States.
| | - R A Royer
- GE Global Research, One Research Circle, Niskayuna, NY 12309, United States.
| | - T C Sale
- Colorado State University, Department of Civil and Environmental Engineering, 1320 Campus Delivery, Fort Collins, CO 80523-1320, United States.
| |
Collapse
|
8
|
Venkataraman P, Sunkara B, St Dennis JE, He J, John VT, Bose A. Water-in-trichloroethylene emulsions stabilized by uniform carbon microspheres. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:1058-1063. [PMID: 22181984 DOI: 10.1021/la204215x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Uniform hard carbon spheres (HCS), synthesized by the hydrothermal decomposition of sucrose followed by pyrolysis, are effective at stabilizing water-in-trichloroethylene (TCE) emulsions. The irreversible adsorption of carbon particles at the TCE-water interface resulting in the formation of a monolayer around the water droplet in the emulsion phase is identified as the key reason for emulsion stability. Cryogenic scanning electron microscopy was used to image the assembly of carbon particles clearly at the TCE-water interface and the formation of bilayers in regions of droplet-droplet contact. The results of this study have potential implications to the subsurface injection of carbon submicrometer particles containing zero-valent iron nanoparticles to treat pools of chlorinated hydrocarbons that are sequestered in fractured bedrock.
Collapse
Affiliation(s)
- Pradeep Venkataraman
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, USA
| | | | | | | | | | | |
Collapse
|
9
|
Lewis S, Lynch A, Bachas L, Hampson S, Ormsbee L, Bhattacharyya D. Chelate-Modified Fenton Reaction for the Degradation of Trichloroethylene in Aqueous and Two-Phase Systems. ENVIRONMENTAL ENGINEERING SCIENCE 2009; 26:849-859. [PMID: 20418966 PMCID: PMC2858874 DOI: 10.1089/ees.2008.0277] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The primary objective of this research was to model and understand the chelate-modified Fenton reaction for the destruction of trichloroethylene (TCE) present in both the aqueous and organic (in the form of droplets) phases. The addition of a nontoxic chelate (L), such as citrate or gluconic acid, allows for operation at near-neutral pH and controlled release of Fe(II)/Fe(III). For the standard Fenton reaction at low pH in two-phase systems, an optimum H(2)O(2):Fe(II) molar ratio was found to be between 1:1 and 2:1. Experimentation proved the chelate-modified Fenton reaction effectively dechlorinated TCE in both the aqueous and organic phases at pH 6-7 using low H(2)O(2):Fe(II) molar ratios (4:1 to 8:1). Increasing the L:Fe ratio was found to decrease the rate of H(2)O(2) degradation in both Fe(II) and Fe(III) systems at near-neutral pH. Generalized models were developed to predict the concentration of TCE in the aqueous phase and TCE droplet radius as a function of time using literature-reported hydroxyl radical reaction kinetics and mass transfer relationships. Additional aspects of this work include the reusability of the Fe-citrate complex under repeated H(2)O(2) injections in real water systems as well as packed column studies for simulated groundwater injection.
Collapse
Affiliation(s)
- Scott Lewis
- Department of Chemical and Materials Engineering, University of
Kentucky, Lexington, Kentucky
| | - Andrew Lynch
- Department of Chemical and Materials Engineering, University of
Kentucky, Lexington, Kentucky
| | - Leonidas Bachas
- Department of Chemistry, University of Kentucky, Lexington,
Kentucky
| | - Steve Hampson
- Kentucky Research Consortium for Energy and Environment, University of
Kentucky, Lexington, Kentucky
| | - Lindell Ormsbee
- Kentucky Research Consortium for Energy and Environment, University of
Kentucky, Lexington, Kentucky
| | - Dibakar Bhattacharyya
- Department of Chemical and Materials Engineering, University of
Kentucky, Lexington, Kentucky
- Corresponding author: Department of Chemical and Materials
Engineering, Kentucky Research Consortium for Energy and Environment, 177 F. Paul Anderson
Tower, University of Kentucky, Lexington, KY 40506-0046. Phone: 859-257-2794;
Fax: 859-323-1929; E-mail:
| |
Collapse
|
10
|
Dai LL, Tarimala S, Wu CY, Guttula S, Wu J. The structure and dynamics of microparticles at pickering emulsion interfaces. SCANNING 2008; 30:87-95. [PMID: 18241040 DOI: 10.1002/sca.20087] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have employed a laser scanning confocal microscope (LSCM) to study the structure and dynamics of microparticles at Pickering emulsion interfaces. The microparticles can have rich morphology at the emulsion interfaces, ranging from an aggregated structure to colloidal lattices, with a possibility of involving heterogeneous particles. With a specific interest in colloidal lattices, we find that although the enhanced electrostatic repulsion explains the formation of colloidal lattices by sulfate-treated polystyrene (S-PS) particles, it fails to interpret the unsuccessfulness of assembling lattices containing single-species carboxylate-treated polystyrene (C-PS) particles. A small percentage of C-PS particles in the colloidal mixture does not disturb the formation of lattices made of S-PS particles. The LSCM also provides a meaningful way to probe dynamic information. The diffusion of single particles at the emulsion interfaces depends strongly on the oil phase viscosity, particle size, and particle wettability. A highly curved emulsion interface slows the motion of microparticles at oil-water interfaces but the interface curvature effect decreases with increasing oil phase viscosity. Although the confocal microscope was originally used as an imaging tool, we find that the thermodynamic equilibrium of colloidal lattices can be disturbed and even destroyed when increasing the output laser intensity.
Collapse
Affiliation(s)
- Lenore L Dai
- Department of Chemical Engineering, Texas Tech University, Lubbock, Texas 79409, USA.
| | | | | | | | | |
Collapse
|
11
|
Torres L, Iturbe R, Snowden MJ, Chowdhry B, Leharne S. Can Pickering emulsion formation aid the removal of creosote DNAPL from porous media? CHEMOSPHERE 2008; 71:123-132. [PMID: 17988711 DOI: 10.1016/j.chemosphere.2007.09.053] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Revised: 09/25/2007] [Accepted: 09/26/2007] [Indexed: 05/25/2023]
Abstract
The purpose of this investigation was to examine the proposition that creosote, emplaced in an initially water saturated porous system, can be removed from the system through Pickering emulsion formation. Pickering emulsions are dispersions of two immiscible fluids in which coalescence of the dispersed phase droplets is hindered by the presence of colloidal particles adsorbed at the interface between the two immiscible fluid phases. Particle trapping is strongly favoured when the wetting properties of the particles are intermediate between strong water wetting and strong oil wetting. In this investigation the necessary chemical conditions for the formation of physically stable creosote-in-water emulsions protected against coalescence by bentonite particles were examined. It was established that physically stable emulsions could be formed through the judicious addition of small amounts of sodium chloride and the surfactant cetyl-trimethylammonium bromide. The stability of the emulsions was initially established by visual inspection. However, experimental determinations of emulsion stability were also undertaken by use of oscillatory rheology. Measurements of the elastic and viscous responses to shear indicated that physically stable emulsions were obtained when the viscoelastic systems showed a predominantly elastic response to shearing. Once the conditions were established for the formation of physically stable emulsions a "proof-of-concept" chromatographic experiment was carried out which showed that creosote could be successfully removed from a saturated model porous system.
Collapse
Affiliation(s)
- Luis Torres
- Instituto de Ingeniería, Coordinación de Ingeniería Ambiental, Universidad Nacional Autónoma de México, Apartado Postal 40-742 Coyoacan, México, DF, Mexico
| | | | | | | | | |
Collapse
|
12
|
Yaron-Marcovich D, Dror I, Berkowitz B. Behavior and stability of organic contaminant droplets in aqueous solutions. CHEMOSPHERE 2007; 69:1593-601. [PMID: 17617437 DOI: 10.1016/j.chemosphere.2007.05.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 05/21/2007] [Accepted: 05/21/2007] [Indexed: 05/16/2023]
Abstract
The behavior of several hydrophobic organic compounds (HOCs) in water at concentrations close to and above their maximum solubility values was studied. For this purpose, solutions of benzene, toluene, xylene, trichloroethylene (TCE) and a mixture of them were prepared in excess in freshwater and in saltwater, and solution stability was examined. High organic concentrations were found to remain stable in both freshwater and saltwater. In saltwater, for example, toluene and xylene concentrations remained as high as 14 and 26 times their solubilities, respectively, over a period of 6 days, while in freshwater, their concentrations remained 8 and 30 times their solubilities over the same period. This phenomenon is attributed to the presence of stable organic droplets, which were observed using optical microscopy. In addition, the transport of HOC droplets through sand is demonstrated, using an experimental system consisting of a saltwater source reservoir connected by a porous inactive sand layer to a freshwater collector reservoir.
Collapse
Affiliation(s)
- Dana Yaron-Marcovich
- Department of Environmental Sciences and Energy Research, Weizmann Institute of Science, Rehovot 76100, Israel
| | | | | |
Collapse
|