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1. Kinetics and Mechanism of Ultrasonic Activation of Persulfate: An in Situ EPR Spin Trapping Study

Author:
Wei Zongsu; Villamena Frederick A.; Weavers Linda K.
Source:
Environmental Science & Technology 2017 v.51 no.6 pp. 3410-3417
ISSN:
1520-5851
Subject:
alcohols; ambient temperature; aqueous solutions; bubbles; dissociation; electron paramagnetic resonance spectroscopy; equations; heat; hydrolysis; hydroxyl radicals; kinetics; oxidation; sulfates; ultrasonics; United States
Abstract:
... Ultrasound (US) was shown to activate persulfate (PS) providing an alternative activation method to base or heat as an in situ chemical oxidation (ISCO) method. The kinetics and mechanism of ultrasonic activation of PS were examined in aqueous solution using an in situ electron paramagnetic resonance (EPR) spin trapping technique and radical trapping with probe compounds. Using the spin trap, 5,5- ...
DOI:
10.1021/acs.est.6b05392

2. Oxidation Removal of Nitric Oxide from Flue Gas Using UV Photolysis of Aqueous Hypochlorite

Author:
Liu Yangxian; Wang Yan; Liu Ziyang; Wang Qian
Source:
Environmental Science & Technology 2017 v.51 no.20 pp. 11950-11959
ISSN:
1520-5851
Subject:
absorption; calcium; carbon dioxide; environmental science; equations; flue gas; hydroxyl radicals; light intensity; mathematical models; nitric oxide; oxidation; oxygen; pH; photolysis; sodium hypochlorite; spraying; sulfur dioxide; temperature
Abstract:
... The oxidation removal of nitric oxide (NO) from flue gas using UV photolysis of aqueous hypochlorite (Ca(ClO)₂ and NaClO) in a photochemical spraying reactor was studied. The key parameters (e.g., light intensity, hypochlorite concentration, solution temperature, solution pH, and concentration of NO, SO₂, O₂, and CO₂), mechanism and kinetics of NO oxidation removal were investigated. The results d ...
DOI:
10.1021/acs.est.7b03628

3. Use of Multiple Linear Regression Models for Setting Water Quality Criteria for Copper: A Complementary Approach to the Biotic Ligand Model

Author:
Brix Kevin V.; DeForest David K.; Tear Lucinda; Grosell Martin; Adams William J.
Source:
Environmental Science & Technology 2017 v.51 no.9 pp. 5182-5192
ISSN:
1520-5851
Subject:
United States Environmental Protection Agency; bioavailability; carbon; copper; covariance; environmental assessment; equations; freshwater; guidelines; hardness; hydrochemistry; ligands; linear models; pH; regression analysis; risk assessment; toxicity; water quality; water quality criteria; water quality standards; Europe
Abstract:
... Biotic Ligand Models (BLMs) for metals are widely applied in ecological risk assessments and in the development of regulatory water quality guidelines in Europe, and in 2007 the United States Environmental Protection Agency (USEPA) recommended BLM-based water quality criteria (WQC) for Cu in freshwater. However, to-date, few states have adopted BLM-based Cu criteria into their water quality standa ...
DOI:
10.1021/acs.est.6b05533

4. Kinetics of Brominated Flame Retardant (BFR) Releases from Granules of Waste Plastics

Author:
Sun Bingbing; Hu Yuanan; Cheng Hefa; Tao Shu
Source:
Environmental Science & Technology 2016 v.50 no.24 pp. 13419-13427
ISSN:
1520-5851
Subject:
activation energy; ambient temperature; computers; diffusivity; electronic wastes; emissions; equations; ethane; flame retardants; granules; half life; human health; plastics; polybrominated diphenyl ethers
Abstract:
... Plastic components of e-waste contain high levels of brominated flame retardants (BFRs), whose releases cause environmental and human health concerns. This study characterized the release kinetics of polybrominated diphenyl ethers (PBDEs) from millimeter-sized granules processed from the plastic exteriors of two scrap computer displays at environmentally relevant temperatures. The release rate of ...
DOI:
10.1021/acs.est.6b04297

5. Probing the Photosensitizing and Inhibitory Effects of Dissolved Organic Matter by Using N,N-dimethyl-4-cyanoaniline (DMABN)

Author:
Leresche Frank; von Gunten Urs; Canonica Silvio
Source:
Environmental Science & Technology 2016 v.50 no.20 pp. 10997-11007
ISSN:
1520-5851
Subject:
singlet oxygen; dissolved organic matter; photosensitizing agents; antibiotics; equations; models; phenol; sulfadiazine; beta-adrenergic antagonists; irradiation; surface water; ultraviolet radiation; formaldehyde
Abstract:
... Dissolved organic matter (DOM) can act as a photosensitizer and an inhibitor in the phototransformation of several nitrogen-containing organic contaminants in surface waters. The present study was performed to select a probe molecule that is suitable to measure these antagonistic properties of DOM. Out of nine studied nitrogen-containing aromatic compounds, 4-cyanoaniline, N,N-dimethyl-4-cyanoanil ...
DOI:
10.1021/acs.est.6b02868

6. Simulating Gas–Liquid−Water Partitioning and Fluid Properties of Petroleum under Pressure: Implications for Deep-Sea Blowouts

Author:
Gros Jonas; Reddy Christopher M.; Nelson Robert K.; Socolofsky Scott A.; Arey J. Samuel
Source:
Environmental Science & Technology 2016 v.50 no.14 pp. 7397-7408
ISSN:
1520-5851
Subject:
bubbles; comprehensive two-dimensional gas chromatography; droplets; equations; hydrocarbons; models; oils; petroleum; prediction; temperature; thermodynamics; viscosity
Abstract:
... With the expansion of offshore petroleum extraction, validated models are needed to simulate the behaviors of petroleum compounds released in deep (>100 m) waters. We present a thermodynamic model of the densities, viscosities, and gas–liquid−water partitioning of petroleum mixtures with varying pressure, temperature, and composition based on the Peng–Robinson equation-of-state and the modified He ...
DOI:
10.1021/acs.est.5b04617

7. Decabrominated Diphenyl Ethers (BDE-209) in Chinese and Global Air: Levels, Gas/Particle Partitioning, and Long-Range Transport: Is Long-Range Transport of BDE-209 Really Governed by the Movement of Particles?

Author:
Li Yi-Fan; Qiao Li-Na; Ren Nan-Qi; Sverko Ed; Mackay Donald; Macdonald Robie W.
Source:
Environmental Science & Technology 2017 v.51 no.2 pp. 1035-1042
ISSN:
1520-5851
Subject:
air; ambient temperature; detection limit; equations; monitoring; partition coefficients; polybrominated diphenyl ethers; volatile organic compounds; Arctic region; China
Abstract:
... In this paper, we report air concentrations of BDE-209 in both gas- and particle-phases across China. The annual mean concentrations of BDE-209 were from below detection limit (BDL) to 77.0 pg·m–³ in the gas-phase and 1.06–728 pg·m–³ in the particle-phase. Among the nine PBDEs measured, BDE-209 is the dominant congener in Chinese atmosphere in both gas and particle phases. We predicted the partiti ...
DOI:
10.1021/acs.est.6b05395

8. Experimental Determination of Isotope Enrichment Factors – Bias from Mass Removal by Repetitive Sampling

Author:
Buchner Daniel; Jin Biao; Ebert Karin; Rolle Massimo; Elsner Martin; Haderlein Stefan B.
Source:
Environmental Science & Technology 2017 v.51 no.3 pp. 1527-1536
ISSN:
1520-5851
Subject:
closed loop systems; equations; experimental design; headspace analysis; isotope fractionation; stable isotopes; volatile compounds; volatilization
Abstract:
... Application of compound-specific stable isotope approaches often involves comparisons of isotope enrichment factors (ε). Experimental determination of ε-values is based on the Rayleigh equation, which relates the change in measured isotope ratios to the decreasing substrate fractions and is valid for closed systems. Even in well-controlled batch experiments, however, this requirement is not necess ...
DOI:
10.1021/acs.est.6b03689

9. Free Diffusivity of Icosahedral and Tailed Bacteriophages: Experiments, Modeling, and Implications for Virus Behavior in Media Filtration and Flocculation

Author:
Baltus Ruth E.; Badireddy Appala Raju; Delavari Armin; Chellam Shankararaman
Source:
Environmental Science & Technology 2017 v.51 no.3 pp. 1433-1440
ISSN:
1520-5851
Subject:
bacteriophages; diffusivity; equations; filtration; flocculation; light scattering; models; prediction
Abstract:
... The aqueous bulk diffusivities of several near-spherical (icosahedral) and nonspherical (tailed) bacterial viruses were experimentally determined by measuring their flux across large pore membranes and using dynamic light scattering, with excellent agreement between values measured using the two techniques. For the icosahedral viruses, good agreement was also found between measured diffusivity val ...
DOI:
10.1021/acs.est.6b05323

10. Glyoxal and Methylglyoxal Setschenow Salting Constants in Sulfate, Nitrate, and Chloride Solutions: Measurements and Gibbs Energies

Author:
Waxman Eleanor M.; Elm Jonas; Kurtén Theo; Mikkelsen Kurt V.; Ziemann Paul J.; Volkamer Rainer
Source:
Environmental Science & Technology 2015 v.49 no.19 pp. 11500-11508
ISSN:
1520-5851
Subject:
Gibbs free energy; aerosols; ammonium nitrate; ammonium sulfate; cations; equations; models; salt concentration; sodium; sodium chloride; sodium nitrate; uncertainty
Abstract:
... Knowledge about Setschenow salting constants, KS, the exponential dependence of Henry’s Law coefficients on salt concentration, is of particular importance to predict secondary organic aerosol (SOA) formation from soluble species in atmospheric waters with high salt concentrations, such as aerosols. We have measured KS of glyoxal and methylglyoxal for the atmospherically relevant salts (NH₄)₂SO₄, ...
DOI:
10.1021/acs.est.5b02782

11. Henry’s Constants of Persistent Organic Pollutants by a Group-Contribution Method Based on Scaled-Particle Theory

Author:
Razdan Neil K.; Koshy David M.; Prausnitz John M.
Source:
Environmental Science & Technology 2017 v.51 no.21 pp. 12466-12472
ISSN:
1520-5851
Subject:
chlorinated naphthalenes; energy; equations; hydrogen; models; persistent organic pollutants; polybrominated diphenyl ethers; polychlorinated biphenyls; polychlorinated dibenzodioxins; polychlorinated dibenzofurans; temperature
Abstract:
... A group-contribution method based on scaled-particle theory was developed to predict Henry’s constants for six families of persistent organic pollutants: polychlorinated benzenes, polychlorinated biphenyls, polychlorinated dibenzodioxins, polychlorinated dibenzofurans, polychlorinated naphthalenes, and polybrominated diphenyl ethers. The group-contribution model uses limited experimental data to o ...
DOI:
10.1021/acs.est.7b03023

12. Identification of Biokinetic Models Using the Concept of Extents

Author:
Mašić Alma; Srinivasan Sriniketh; Billeter Julien; Bonvin Dominique; Villez Kris
Source:
Environmental Science & Technology 2017 v.51 no.13 pp. 7520-7531
ISSN:
1520-5851
Subject:
biotechnology; equations; mathematical models; wastewater treatment
Abstract:
... The development of a wide array of process technologies to enable the shift from conventional biological wastewater treatment processes to resource recovery systems is matched by an increasing demand for predictive capabilities. Mathematical models are excellent tools to meet this demand. However, obtaining reliable and fit-for-purpose models remains a cumbersome task due to the inherent complexit ...
DOI:
10.1021/acs.est.7b00250

13. Modeling Bisolute Adsorption of Aromatic Compounds Based on Adsorbed Solution Theories

Author:
Zhang Huichun; Wang Shubo
Source:
Environmental Science & Technology 2017 v.51 no.10 pp. 5552-5562
ISSN:
1520-5851
Subject:
Gibbs free energy; adsorption; aromatic compounds; equations; models; municipal wastewater; polystyrenes; prediction; solutes; sorption isotherms
Abstract:
... A large number of organic contaminants are commonly found in industrial and municipal wastewaters. For proper unit design to remove contaminant mixtures by adsorption, multicomponent adsorption equilibrium models are necessary. The present work examined the applicability of Ideal Adsorbed Solution Theory (IAST), a prevailing thermodynamic model, and its derivatives, i.e., Segregated IAST (SIAST) a ...
DOI:
10.1021/acs.est.6b05576

14. Prediction of Adsorption Equilibrium of VOCs onto Hyper-Cross-Linked Polymeric Resin at Environmentally Relevant Temperatures and Concentrations Using Inverse Gas Chromatography

Author:
Jia Lijuan; Ma Jiakai; Shi Qiuyi; Long Chao
Source:
Environmental Science & Technology 2017 v.51 no.1 pp. 522-530
ISSN:
1520-5851
Subject:
acetone; adsorbents; adsorption; benzene; equations; gas chromatography; hexane; methylene chloride; nitrogen; porous media; prediction; temperature; volatile organic compounds
Abstract:
... Hyper-cross-linked polymeric resin (HPR) represents a class of predominantly microporous adsorbents and has good adsorption performance toward VOCs. However, adsorption equilibrium of VOCs onto HPR are limited. In this research, a novel method for predicting adsorption capacities of VOCs on HPR at environmentally relevant temperatures and concentrations using inverse gas chromatography data was pr ...
DOI:
10.1021/acs.est.6b05039

15. Quantum Chemically Estimated Abraham Solute Parameters Using Multiple Solvent–Water Partition Coefficients and Molecular Polarizability

Author:
Liang Yuzhen; Xiong Ruichang; Sandler Stanley I.; Di Toro Dominic M.
Source:
Environmental Science & Technology 2017 v.51 no.17 pp. 9887-9898
ISSN:
1520-5851
Subject:
Gibbs free energy; chemical structure; energy; environmental science; equations; methodology; models; partition coefficients; prediction; regression analysis; solutes
Abstract:
... Polyparameter Linear Free Energy Relationships (pp-LFERs), also called Linear Solvation Energy Relationships (LSERs), are used to predict many environmentally significant properties of chemicals. A method is presented for computing the necessary chemical parameters, the Abraham parameters (AP), used by many pp-LFERs. It employs quantum chemical calculations and uses only the chemical’s molecular s ...
DOI:
10.1021/acs.est.7b01737

16. Temperature Dependence of the Photochemical Formation of Hydroxyl Radical from Dissolved Organic Matter

Author:
McKay Garrett; Rosario-Ortiz Fernando L.
Source:
Environmental Science & Technology 2015 v.49 no.7 pp. 4147-4154
ISSN:
1520-5851
Subject:
activation energy; benzene; benzoquinones; catalase; dissolved organic matter; equations; fractionation; humic substances; hydrogen peroxide; hydroxyl radicals; models; molecular weight; oxidation; phenol; photolysis; temperature
Abstract:
... The temperature dependence of the photochemical production of the hydroxyl radical (•OH) from dissolved organic matter (DOM) was investigated by measuring the apparent temperature dependence of the quantum yield (Φₐ) for this process. Temperature dependent Φₐ values were analyzed using the Arrhenius equation. Apparent activation energies obtained for DOM isolates purchased from the International H ...
DOI:
10.1021/acs.est.5b00102

17. Anionic, Cationic, and Nonionic Surfactants in Atmospheric Aerosols from the Baltic Coast at Askö, Sweden: Implications for Cloud Droplet Activation

Author:
Gérard Violaine; Nozière Barbara; Baduel Christine; Fine Ludovic; Frossard Amanda A.; Cohen Ronald C.
Source:
Environmental Science & Technology 2016 v.50 no.6 pp. 2974-2982
ISSN:
1520-5851
Subject:
aerosols; chlorophyll; coasts; colorimetry; equations; micelles; nonionic surfactants; particulates; seawater; surface tension; titration; Sweden
Abstract:
... Recent analyses of atmospheric aerosols from different regions have demonstrated the ubiquitous presence of strong surfactants and evidenced surface tension values, σ, below 40 mN m–¹, suspected to enhance the cloud-forming potential of these aerosols. In this work, this approach was further improved and combined with absolute concentration measurements of aerosol surfactants by colorimetric titra ...
DOI:
10.1021/acs.est.5b05809

18. Chemical Reactivity Probes for Assessing Abiotic Natural Attenuation by Reducing Iron Minerals

Author:
Fan Dimin; Bradley Miranda J.; Hinkle Adrian W.; Johnson Richard L.; Tratnyek Paul G.
Source:
Environmental Science & Technology 2016 v.50 no.4 pp. 1868-1876
ISSN:
1520-5851
Subject:
aquifers; carbon tetrachloride; electrodes; electron transfer; equations; groundwater contamination; iron; minerals; models; solvents; thermodynamics
Abstract:
... Increasing recognition that abiotic natural attenuation (NA) of chlorinated solvents can be important has created demand for improved methods to characterize the redox properties of the aquifer materials that are responsible for abiotic NA. This study explores one promising approach: using chemical reactivity probes (CRPs) to characterize the thermodynamic and kinetic aspects of contaminant reduct ...
DOI:
10.1021/acs.est.5b05800

19. Co-precipitation of Radium with Barium and Strontium Sulfate and Its Impact on the Fate of Radium during Treatment of Produced Water from Unconventional Gas Extraction

Author:
Zhang Tieyuan; Gregory Kelvin; Hammack Richard W.; Vidic Radisav D.
Source:
Environmental Science & Technology 2014 v.48 no.8 pp. 4596-4603
ISSN:
1520-5851
Subject:
adsorption; barite; barium; barium sulfate; coprecipitation; equations; ionic strength; ions; landfills; monitoring; radium; recycling; salinity; strontium; strontium sulfate; waste treatment; wastewater; water treatment
Abstract:
... Radium occurs in flowback and produced waters from hydraulic fracturing for unconventional gas extraction along with high concentrations of barium and strontium and elevated salinity. Radium is often removed from this wastewater by co-precipitation with barium or other alkaline earth metals. The distribution equation for Ra in the precipitate is derived from the equilibrium of the lattice replacem ...
DOI:
10.1021/es405168b

20. Computer-Based First-Principles Kinetic Monte Carlo Simulation of Polyethylene Glycol Degradation in Aqueous Phase UV/H2O2 Advanced Oxidation Process

Author:
Guo Xin; Minakata Daisuke; Crittenden John
Source:
Environmental Science & Technology 2014 v.48 no.18 pp. 10813-10820
ISSN:
1520-5851
Subject:
Monte Carlo method; byproducts; equations; hydrogen peroxide; models; molecular weight; oxidation; polyethylene glycol; prediction
Abstract:
... We have developed a computer-based first-principles kinetic Monte Carlo (CF-KMC) model to predict degradation mechanisms and fates of intermediates and byproducts produced from the degradation of polyethylene glycol (PEG) in the presence of hydrogen peroxide (UV/H₂O₂). The CF-KMC model is composed of a reaction pathway generator, a reaction rate constant estimator, and a KMC solver. The KMC solver ...
DOI:
10.1021/es5029553