Dechlorination of endocrine disrupting chemicals using Mg0/ZnCl2 bimetallic system

Defunctionalization of organochlorines through reductive dechlorination (also known as hydrodechlorination-replacement of chlorine atoms by hydrogen-is one of the main methodologies used in the detoxification of these harmful compounds. Most of the published papers on this particular matter focused on specific reagents, reaction conditions, and mainly result efficiency. Some of the authors were also concerned with reaction pathways (e.g., the order in which chlorine atoms were removed from a polychlorinated aromatic substrate-polychlorinated biphenyls, PCBs; polychlorinated dibenzo-p-dioxins, PCDDs; or polychlorinated dibenzofurans, PCDFs). However, the papers that dealt with the investigation of reaction mechanism were rather scarce. This chapter presents the advances made by researchers in understanding, from a mechanistic point of view, the hydrodechlorination process, along with our own assumptions. In doing so, it would be easier to predict the behavior of such compounds in a specific environment, showing more clearly the scope and limitations of each process, depending on the reaction conditions and reagents.

show abstract

“…Analogous conclusions were drawn for bimetallic systems such as Fe/Ni [98], Mg/Zn [99], or Ni/Mo [100].…”

Section: Organochlorinesupporting

confidence: 55%

Mechanistic Considerations on the Hydrodechlorination Process of Polychloroarenes

Mitoma¹,

Katayama²,

Simion³

2018

Organochlorine

View full text Add to dashboard Cite

show abstract

“…However further decrease in pH up to 2.1 does not resulted in higher degradation efficiency. This can be explained by intensive corrosion of iron at extremely acidic pH which results in (a) abrupt production of hydrogen which may produce a blanket of gas bubbles around the Pd surface inhibiting the contact of ␥-HCH molecules to nanoparticles [15] (b) provides lesser time to catalyst to adsorb and dissociate H 2 [45], hence overall degradation efficiency decreases. At higher pH, Fe(II) and Fe(III) from iron surface and OH − ions in the alkaline solution reacted to precipitate iron oxides/hydroxides on the surface of iron occupying the reactive sites, thus hindering the access of ␥-HCH molecules to the reactive sites, reducing degradation.…”

Section: Effect Of Initial Phmentioning

confidence: 99%

Degradation of γ-HCH spiked soil using stabilized Pd/Fe0 bimetallic nanoparticles: Pathways, kinetics and effect of reaction conditions

Singh

Misra

Mudiam

et al. 2012

Journal of Hazardous Materials

View full text Add to dashboard Cite

“…Recently, the environmental problem caused by endocrine disrupting chemicals (EDCs) contamination has become the discussion focus of the public and regulatory agencies due to its harmful and hazardous effects to wildlife and human health [1]. The EDCs with the structural and functional similarity as entogenous estrogen can alter the functions of the endocrine systems and consequently cause adverse health effects to an intact organism, or its progeny or (sub) populations [2]. Most seriously, the EDCs have potential harmful impacts on the hormonal control, sexual differentiation, reproductive success, and community structure of aquatic organisms and their offspring even at extremely low concentrations [3].…”

Section: Introductionmentioning

confidence: 99%

Synthesis of a Cationic Polyacrylamide under UV Initiation and Its Flocculation in Estrone Removal

Sun

et al. 2018

International Journal of Polymer Science

View full text Add to dashboard Cite

A ternary cationic polyacrylamide (CPAM) with the hydrophobic characteristic was prepared through ultraviolet-(UV-) initiated polymerization technique for the estrone (E1) environmental estrogen separation and removal. The monomers of acrylamide (AM), acryloyloxyethyl-trimethyl ammonium chloride (DAC), and acryloyloxyethyl dimethylbenzyl ammonium chloride (AODBAC) were used to synthesize the ternary copolymer (PADA). Fourier transform infrared spectroscopy (FT-IR), 1 H nuclear magnetic resonance spectroscopy ( 1 H NMR), thermogravimetry/differential scanning calorimetry (TG/DSC), and scanning electron microscopy (SEM) were employed to characterize the structure, thermal decomposition property, and morphology of the polymers, respectively. FT-IR and 1 H NMR results indicated the successful formation of the polymers. Besides, with the introduction of hydrophobic groups (phenyl group), an irregular and porous surface morphology and a favorable thermal stability of the PADA were observed by SEM and TG/DSC analyses, respectively. At the optimal condition (pH = 7, flocculant dosage = 4.0 mg/L and E1 concentration = 0.75 mg/L), an excellent E1 flocculation performance (E1 removal rate: 90.1%, floc size: 18.3 m, and flocculation kinetics: 22.69 × 10 −4 s −1 ) was acquired by using the efficient flocculant PADA-3 (cationic degree = 40%, and intrinsic viscosity = 6.30 dL⋅g −1 ). The zeta potential and floc size analyses were used to analyze the possible flocculation mechanism for the E1 removal. Results indicated that the charge neutralization, adsorption, and birding effects were dominant in the E1 removal progress.

show abstract

Dechlorination of endocrine disrupting chemicals using Mg0/ZnCl2 bimetallic system

Cited by 18 publications

References 19 publications

Mechanistic Considerations on the Hydrodechlorination Process of Polychloroarenes

Mechanistic Considerations on the Hydrodechlorination Process of Polychloroarenes

Degradation of γ-HCH spiked soil using stabilized Pd/Fe0 bimetallic nanoparticles: Pathways, kinetics and effect of reaction conditions

Synthesis of a Cationic Polyacrylamide under UV Initiation and Its Flocculation in Estrone Removal

Contact Info

Product

Resources

About