Aliphatic amines are abundant micropollutants in wastewater treatment plant effluents. In order to mitigate such micropollutants, ozonation is one of the most commonly employed advanced treatment processes. Current research regarding ozone efficiency is heavily focusing on reaction mechanisms of different contaminant groups, including structures with amine moieties as reactive sites. This study analyzes pH-dependent reaction kinetics and pathways of gabapentin (GBP), an aliphatic primary amine with an additional carboxylic acid group. The transformation pathway was elucidated applying a novel approach using isotopically labeled ozone (O) and quantum chemistry calculations. While the direct reaction of GBP with ozone is highly pH-dependent and slow at pH 7 (13.7 M s), the rate constant of the deprotonated species (1.76 × 10 M s) is comparable to those of other amine compounds. Pathway analysis based on LC-MS/MS measurements revealed that ozonation of GBP leads to the formation of a carboxylic acid group and simultaneous nitrate formation, which was also observed in the case of the aliphatic amino acid glycine. Nitrate was formed with a yield of approximately 100%. Experiments with O-labeled ozone demonstrated that the intermediate aldehyde does most likely not include any oxygen originating from ozone. Furthermore, quantum chemistry calculations did not provide an explanation for the C-N scission during GBP ozonation without ozone involvement, although this reaction was slightly more favorable than for respective glycine and ethylamine reactions. Overall, this study contributes to a deeper understanding of reaction mechanisms of aliphatic primary amines during wastewater ozonation.
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http://dx.doi.org/10.1021/acs.est.2c06709 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Key Laboratory of Bio-based Polymeric Materials Technology and Application of Zhejiang Province, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, 1219 Zhongguan West Road, Ningbo 315201, China.
2,5-Furandicarboxylic acid (FDCA) is one of the top selected value-added chemicals, which can be obtained by the aerobic oxidation of 2,5-bis(hydroxymethyl)furfural (BHMF) over a Pd-based catalyst. However, the elucidation of the reaction mechanism was hindered by its rapid kinetics. Herein, employing the density functional theory (DFT) calculations, we delve into the detailed reaction pathways of the BHMF oxidation into FDCA over Pd(111) and PdH(111) identifying the rate-determining steps.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Chang Chun Institute of Applied Chemistry Chinese Academy of Sciences, Key Laboratory of Polymer Ecomaterials, 5625 Renmin Street, Changchun, , 130022, Changchun, CHINA.
Living cationic polymerization (LCP) is a classical technique for precision polymer synthesis; however, due to the high sensitivity of cationic active species towards chain-transfer/termination events, it is notoriously difficult to control polymerization under mild conditions, which inhibits its progress in advanced materials engineering. Here, we unlock a practical anion-binding catalytic strategy to address the historical dilemma in LCP. Our experimental and mechanistic studies demonstrate that commercially accessible hexafluoroisopropanol (HFIP), when used in high loading, can create higher-order HFIP aggregates to tame dormant-active species equilibrium via non-covalent anion-binding principle, in turn inducing distinctive polymerization kinetics behaviors that grant efficient chain propagation while minimizing competitive side reactions.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
State Key Laboratory of Physical Chemistry of Solid Surface, Fujian Key Laboratory of Surface and Interface Engineering for High Performance Materials, College of Materials, Xiamen University, Xiamen 361005, China.
Sluggish redox kinetics and dendrite growth perplex the fulfillment of efficient electrochemistry in lithium-sulfur (Li-S) batteries. The complicated sulfur phase transformation and sulfur/lithium diversity kinetics necessitate an all-inclusive approach in catalyst design. Herein, a compatible mediator with nanoscale-asymmetric-size configuration by integrating Co single atoms and defective CoTe (Co-CoTe@NHCF) is elaborately developed for regulating sulfur/lithium electrochemistry synchronously.
View Article and Find Full Text PDFLangmuir
January 2025
Materials Chemistry Department, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha 751013, India.
Due to the high cost of the available Pt electrocatalysts, the large-scale water electrolysis production of hydrogen has been hindered. Hydrogen generation via electrochemical water splitting is a renewable energy essential to a sustainable society, creating a distinct material interface that shows Pt-like properties with long-term stability crucial to hydrogen evolution reactions (HERs). Here, we synthesized the guanine-assisted facile synthesis of 1 wt % Pt/MoC/C having a layered type morphology via solid state calcined process followed by chemical reduction.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Laboratory for Structural Engineering and Sustainable Catalysis, Department of Chemistry, University of North Bengal, Darjeeling 734013, India.
The upsurging of cost-effective electrocatalysts through the operando electro-oxidation approaches holds great promise for the scalable production of green energy in the pursuit of energy sustainability. This work introduces an operando electro-oxidation reconstitution strategy in producing a smart electrocatalyst, cobalt "oxyhydroxide" derived from a newly designed 2D cobalt(II) metal-organic framework (-) directly grown on nickel foam (NF), . The electrocatalyst, , exhibits an outstanding overpotential of 76 mV for the hydrogen evolution reaction and 336 mV for the oxygen evolution reaction to achieve a current density of 10 mA/cm with remarkable Faradaic efficiencies of 97.
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