American Society for Testing and Materials

External corrosion of oil and gas pipelines: A review of failure mechanisms and predictive preventions

A review on corrosion detection and protection of existing reinforced concrete (RC) structures

Carbonation of concrete at ambient CO2 concentration is a slow process. This makes the testing of the resistance of concrete against carbonation often too slow to be applicable for service life assessments of new structures. Raising the CO2-concentration will accelerate the test but the validity of an increase CO2 -level is debated. If not valid, the service life can be seriously underestimated. In this paper, the effects of accelerating on the carbonation process are discussed. It is shown that a change in CO2 concentration will not change the carbonation process. Since carbonation occurs instantly, a zero CO2 concentration at the carbonation front is maintained. Moreover, it has been concluded that all hydrated and unhydrated cement ultimately carbonate. This implies that the amount of carbonatable matter can be determined on the basis of the amount of calcium in the unreacted cement.

Influence of the carbon dioxide concentration on the resistance to carbonation of concrete

VOLUME I Introduction The Incentive Physical-Chemical Properties Experimental Methods Quantitative Structure-Property Relationships (QSPRs) Mass Balance Models of Chemical Fate Data Sources and Presentation Illustrative QSPR Plots and Fate Calculations References Aliphatic and Cyclic Hydrocarbons Lists of Chemicals and Data Compilations Summary Tables and QSPR plots References Mononuclear Aromatic Hydrocarbons Lists of Chemicals and Data Compilations Summary Tables and QSPR plots References Polynuclear Aromatic Hydrocarbons (PAHs) and Related Aromatic Hydrocarbons Lists of Chemicals and Data Compilations Summary Tables and QSPR plots References VOLUME II * Halogenated Aliphatic Hydrocarbons Chlorobenzenes and Other Halogenated Mononuclear Aromatics Polychlorinated Biphenyls (PCBs) Chlorinated Dibenzop-dioxins Chlorinated Dibenzofurans VOLUME III * Ethers Alcohols Aldehydes and Ketones Carboxylic Acids Phenolic Compounds Esters VOLUME IV Nitrogen and Sulfur Compounds Lists of Chemicals and Data Compilations Summary Tables References Herbicides Lists of Chemicals and Data Compilations Summary Tables References Insecticides Lists of Chemicals and Data Compilations Summary Tables References Fungicides Lists of Chemicals and Data Compilations Summary Tables References APPENDICES List of Symbols and Abbreviations Alphabetical Index CAS Registry Index Molecular Formula Index * Each chapter contains lists of chemicals and data compilations, summary tables, QSPR plots, and references

Handbook of Physical Chemical Properties and Environmental Fate for Organic Chemicals Second Edition 4 Volume Set

https://hal-brgm.archives-ouvertes.fr/hal-02979786/document

Reinforced concrete structures: A review of corrosion mechanisms and advances in electrical methods for corrosion monitoring

Reductive dechlorination of hexachlorobutadiene (HCBD) was performed by a suspension of scattered spots of palladium nanoparticles deposited on iron microparticles (nPd/μZVI) in a mixture of dissolved lactic acid polymers and oligomers (referred to as PLA). The effects of nPd/μZVI loading, temperature, HCBD initial concentration, and PLA content were investigated as to define the best conditions for the dechlorination. HCBD dechlorination by nPd/μZVI occurred in a two-step process: first, HCBD adsorbed onto the nPd surface, which resulted in a rapid initial disappearance of pollutant in solution, and, second, it degraded chemically by atomic hydrogen H*, which resulted from the dissociative adsorption of H2 on nPd. HCBD remained adsorbed on the surface until its complete degradation in nonchlorinated product, in agreement with the formation of an ordered activated complex on the nPd/μZVI surface as suggested by the negative entropy of activation calculated from the Eyring equation. Hence, a minimum amount of nPd/μZVI was required to enable simultaneously HCBD adsorption and H2 production. In these cases, pseudo-first order rate equations were suitable to model HCBD disappearance kinetics. The increase in PLA content resulted in enhancing initial pH decrease such as to maintain acidic conditions and thus high reactivity over a longer period of time. It also resulted in enhancing the contact between HCBD and nPd/μZVI, which was characterized by a more important initial adsorption. As a consequence, deviations from pseudo-first order kinetics were observed and a more representative model with a two-phase decay was proposed.

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Reductive Dechlorination of Hexachlorobutadiene by a Pd/Fe Microparticle Suspension in Dissolved Lactic Acid Polymers: Degradation Mechanism and Kinetics

Chlorinated organic compounds (COCs) are common anthropogenic contaminants encountered in soil and groundwater. COCs were industrially produced for different applications, such as dry cleaning, degreasing, or as pesticides. The presence of COCs in the environment is a major concern because of their toxicity and persistence.

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In Situ Chemical Reduction of Chlorinated Organic Compounds

The solubilization of hexachlorobutadiene (HCBD) and hexachloroethane (HCA) in water as a function of temperature and in the presence of surfactants was investigated in order to predict their fate in groundwater and to increase their recovery. HCBD and HCA solubility data were experimentally determined at five temperatures in the range from (285.15 to 318.15) K. Thermodynamic parameters for dissolution (ΔsolG°, ΔsolH°, and ΔsolS°) have been calculated in order to propose a physical explanation of the minimum solubility observed between 293.15 and 298.15 K for both compounds. The solubilization process appeared to be influenced by the network of water molecules rather than by physical and chemical properties of HCBD or HCA, due to an opposite effect of temperature onto Brownian motion, which increases with temperature, and hydrogen-bond network, which collapses with temperature. Concerning the influence of surfactants, determination of the micelle–water partition coefficients (Kmw) and the molar solubiliza...

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Influence of Temperature and Surfactants on the Solubilization of Hexachlorobutadiene and Hexachloroethane

The degradation mechanism of the pollutant hexachloroethane (HCA) by a suspension of Pd-doped zerovalent iron microparticles (Pd-mZVI) in dissolved lactic acid polymers and oligomers (referred to as PLA) was investigated using gas chromatography and the indirect monitoring of iron corrosion by continuous measurements of pH, oxidation-reduction potential (ORP), and conductivity. The first experiments took place in the absence of HCA, to understand the evolution of the Pd-mZVI/PLA/H2O system. This showed that the evolution of pH, ORP, and conductivity is related to changes in solution chemistry due to iron corrosion and that the system is initially cathodically controlled by H+ mass transport to Pd surfaces because of the presence of an extensive PLA layer. We then investigated the effects of Pd-mZVI particles, temperature, initial HCA concentration, and PLA content on the Pd-mZVI/PLA/HCA/H2O system, to obtain a better understanding of the degradation mechanism. In all cases, HCA dechlorination first requires the production of atomic hydrogen H*—involving the accumulation of tetrachloroethylene (PCE) as an intermediate—before its subsequent reduction to non-chlorinated C2 and C4 compounds. The ratio between Pd-mZVI dosage, initial HCA concentration, and PLA content affects the rate of H* generation as well as the rate-determining step of the process. A pseudo-first-order equation can be applied when Pd-mZVI dosage is much higher than the theoretical stoichiometry (600 mg for [HCA]0 = 5–20 mg L−1). Our results indicate that the HCA degradation mechanism includes mass transfer, sorption, surface reaction with H*, and desorption of the product.

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Elucidating the dechlorination mechanism of hexachloroethane by Pd-doped zerovalent iron microparticles in dissolved lactic acid polymers using chromatography and indirect monitoring of iron corrosion

Romain Rodrigues

Papers

Reinforced concrete structures: A review of corrosion mechanisms and advances in electrical methods for corrosion monitoring

Reductive Dechlorination of Hexachlorobutadiene by a Pd/Fe Microparticle Suspension in Dissolved Lactic Acid Polymers: Degradation Mechanism and Kinetics

In Situ Chemical Reduction of Chlorinated Organic Compounds

Influence of Temperature and Surfactants on the Solubilization of Hexachlorobutadiene and Hexachloroethane

Elucidating the dechlorination mechanism of hexachloroethane by Pd-doped zerovalent iron microparticles in dissolved lactic acid polymers using chromatography and indirect monitoring of iron corrosion