The rate constants of many reactions currently considered to be important in the atmospheric chemistry of mercury remain to be measured in the laboratory. Here we report the first experimental determination of the rate constant of the gas-phase reaction between the HgBr radical and ozone, for which a value at room temperature of (HgBr + O) = (7.5 ± 0.6) × 10 cm molecule s (1) has been obtained. The rate constants of two reduction side reactions were concurrently determined: (HgBr + O) = (5.3 ± 0.4) × 10 cm molecule s and (HgBrO + O) = (9.1 ± 0.6) × 10 cm molecule s. The value of (HgBr + O) is slightly lower than the collision number, confirming the absence of a significant energy barrier. Considering the abundance of ozone in the troposphere, our experimental rate constant supports recent modelling results suggesting that the main atmospheric fate of HgBr is reaction with ozone to form BrHgO.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9131727 | PMC |
| http://dx.doi.org/10.1039/d2cp00754a | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Highly Sensitive Whole-Cell Mercury Biosensors for Environmental Monitoring.
Biosensors (Basel)
May 2024
Laboratorio de Moléculas Individuales, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima 15102, Peru.
Whole-cell biosensors could serve as eco-friendly and cost-effective alternatives for detecting potentially toxic bioavailable heavy metals in aquatic environments. However, they often fail to meet practical requirements due to an insufficient limit of detection (LOD) and high background noise. In this study, we designed a synthetic genetic circuit specifically tailored for detecting ionic mercury, which we applied to environmental samples collected from artisanal gold mining sites in Peru.
View Article and Find Full Text PDFUnderstanding the Impacts of Different Impurities on Elemental Mercury Removal by CaS in Chemical Looping Combustion of Coal: A First Principle Study.
ACS Omega
August 2023
School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
CaSO has the advantages of abundant yield, high oxygen-carrying capacity, low cost, and no heavy metal pollution, making it promising as an oxygen carrier for chemical looping combustion (CLC). In comparison with other oxygen carriers, CaS as the reduced product of CaSO exhibits superior adsorption efficiency for Hg in the flue gas. In this paper, density functional theory (DFT) was used to investigate the adsorption mechanism of Hg on the adsorbent surface of CaS(001).
View Article and Find Full Text PDFIsolation and crystal and molecular structures of [(CHBr)Fe], [(CHBr)Fe] and [(CBr)(CBrHgBr)Fe].
Acta Crystallogr C Struct Chem
November 2022
Chemistry, Ludwig-Maximilians-University Munich, Butenandtstrasse 5-13, Munich, D-81377, Germany.
The reaction of [(CHBr)Fe] with lithium tetramethylpiperidinide (LiTMP) in a 1:10 molar ratio in tetrahydrofuran yields, after quenching with CHBr, a mixture of the polybromoferrocenes [CHBrFe] with n = 4-9, from which single crystals of bis(1,2,3-tribromocyclopentadienyl)iron(II), [Fe(CHBr)], and bis(1,2,3,4-tetrabromocyclopentadienyl)iron(II), [Fe(CHBr)Fe], were obtained by a combination of chromatography and fractional crystallization. Treatment of `[C(HgOAc)Fe]' with KBr yields a mixture of polybromoferrocenes [CHBrFe] with n = 8-10 and bromomercurioferrocenes [CHBr(HgBr)Fe] with n = 7-9, from which single crystals of (1-bromomercurio-2,3,4,5-tetrabromocyclopentadienyl)(1,2,3,4,5-pentabromocyclopentadienyl)iron(II), [FeHgBr(CBr)(CBr)], were obtained by fractional crystallization. The crystal structures of all the compounds show Br.
View Article and Find Full Text PDFThe Effects of Physical-Chemical Evolution of High-Sulfur Petroleum Coke on Hg Removal from Coal-Fired Flue Gas and Exploration of Its Micro-Scale Mechanism.
Int J Environ Res Public Health
June 2022
College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.
As the solid waste by-product from the delayed coking process, high-sulfur petroleum coke (HSPC), which is hardly used for green utilization, becomes a promising raw material for Hg removal from coal-fired flue gas. The effects of the physical-chemical evolution of HSPC on Hg removal are discussed. The improved micropores created by pyrolysis and KOH activation could lead to over 50% of Hg removal efficiency with the loss of inherent sulfur.
View Article and Find Full Text PDFCalibration Approach for Gaseous Oxidized Mercury Based on Nonthermal Plasma Oxidation of Elemental Mercury.
Anal Chem
June 2022
Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia.
Atmospheric mercury measurements carried out in the recent decades have been a subject of bias largely due to insufficient consideration of metrological traceability and associated measurement uncertainty, which are ultimately needed for the demonstration of comparability of the measurement results. This is particularly challenging for gaseous Hg species, which are reactive and their ambient concentrations are very low, causing difficulties in proper sampling and calibration. Calibration for atmospheric Hg exists, but barriers to reliable calibration are most evident at ambient Hg concentration levels.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!