Hydroquinone is considered to be one of the major, potential molecular precursors for semiquinone-type radicals in the combustion of complex polymeric and oligomeric structures contained in biomass materials. Comprehensive product yield determinations from the high-temperature, gas-phase pyrolysis of hydroquinone in two operational modes (rich and lean hydrogen conditions) are reported at a reaction time of 2.0s over a temperature range of 250-1000 degrees C. Below 500 degrees C, p-benzoquinone is the dominant product, while at temperatures above 650 degrees C other products including phenol, benzene, styrene, indene, naphthalene, biphenylene, phenylethyne, dibenzofuran and dibenzo-p-dioxin are formed. Hydrogen-rich conditions initially inhibit hydroquinone decomposition (below 500 degrees C) but promote product formation at higher temperatures. The decomposition process apparently proceeds via formation of a resonance stabilized p-semiquinone radical. Detailed mechanisms of formation of stable molecular species as well as stable radicals are proposed.
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http://dx.doi.org/10.1016/j.chemosphere.2007.10.007 | DOI Listing |
J Hazard Mater
September 2024
Department of Environmental Analysis, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, 80-308, Poland.
Iron-based biochar exhibits great potential in degrading emerging pollutants and remediation of water environments. In this study, a highly efficient catalytic Fe/biochar (MZB-800) was synthesized by the co-pyrolysis of poplar sawdust and KFeO at 800 °C. A novel water purification technology of pre-reduction followed by PMS activation for MZB-800 was proposed to degrade the refractory 2,4-dichlorophenoxyacetic acid (2,4-D) pesticide.
View Article and Find Full Text PDFEnviron Res
July 2024
Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address:
The application of antimony sulfide sensors, characterized by their exceptional stability and selectivity, is of emerging interest in detection research, and the integration of graphitized carbon materials is expected to further enhance their electrochemical performance. This study represents a pioneering effort in the synthesis of carbon-doped antimony sulfide materials through the pyrolysis of the mixture of microorganisms and their synthetic antimony sulfide. The prepared materials are subsequently applied to electrochemical sensors for monitoring the highly toxic compounds catechol (CC) and hydroquinone (HQ) in the environment.
View Article and Find Full Text PDFSci Total Environ
March 2024
Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China. Electronic address:
Environ Res
April 2024
Department of Energy Science and Technology, Environmental Waste Recycle Institute, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea. Electronic address:
Herein, we present the exceptional performance of FeC-coated carbon sheets (FC) derived from the pyrolysis of waste biomass as a bifunctional catalyst for electrochemical detection and catalytic reduction of 4-nitrophenol (4-NP). Despite having a lower surface area, larger particle size, and lesser N content, the FC material prepared at a calcination temperature of 900 °C (FC) outperforms the other samples. Deeper investigations revealed that the FC efficiently facilitates the charge transfer process and enhances the diffusion rate of 4-NP, leading to increased surface coverage of 4-NP on the surface of FC.
View Article and Find Full Text PDFMaterials (Basel)
November 2023
Institute of Chemistry, St. Petersburg State University, St. Petersburg 199034, Russia.
The conversion of metal-organic frameworks (MOFs) into advanced functional materials offers a promising route for producing unique nanomaterials. MOF-derived systems have the potential to overcome the drawbacks of MOFs, such as low electrical conductivity and poor structural stability, which have hindered their real-world applications in certain cases. In this study, laser scribing was used for pyrolysis of a Cu-based MOF ([Cu{1,4-CH(COO)}(4,4'-bipy)]) to synthesize a Cu-CuO@C composite on the surface of a screen-printed electrode (SPE).
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