1
|
Zhao X, Liu Z, Zhao R, Xu T. The effect of (H 2O) n ( n = 1-3) clusters on the reaction of HONO with HCl: a mechanistic and kinetic study. Phys Chem Chem Phys 2022; 24:10011-10024. [PMID: 35415725 DOI: 10.1039/d1cp05792h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction between HONO and HCl is a possible pathway for the generation of ClNO, which is prone to photolyze, produce chlorine radicals, and accelerate the oxidation of tropospheric VOCs. Current experimental and theoretical studies have significant differences in rate constants under similar conditions. This study aims to examine the reasons for this difference. In this study, the effects of a single water molecule, water dimer, water trimer, excess HCl and excess HONO on the reaction mechanism of HONO + HCl were studied at the CCSD(T)/aug-cc-pVTZ//M06-2X/6-311+G(2df,2p) level and the rate constants of each reaction channel were calculated. Our results showed that the reaction potential barrier of HONO with HCl was the lowest only when the water dimer was present, and the reaction rate constants were close to the experimental results, and both the cis-HONO⋯(H2O)2 + HCl and the trans-HONO⋯(H2O)2 + HCl reaction paths are likely to occur. We think that the reason for the inconsistency between experimental and theoretical results is that the water dimer is involved in the reaction in experiments.
Collapse
Affiliation(s)
- Xiaoxia Zhao
- Chemistry and Environment Science College, Inner Mongolia Normal University, Inner Mongolia Key Laboratory of Green Catalysis, Hohhot, Inner Mongolia 010022, China.
| | - Zizhong Liu
- Chemistry and Environment Science College, Inner Mongolia Normal University, Inner Mongolia Key Laboratory of Green Catalysis, Hohhot, Inner Mongolia 010022, China.
| | - Ruisheng Zhao
- Chemistry and Environment Science College, Inner Mongolia Normal University, Inner Mongolia Key Laboratory of Green Catalysis, Hohhot, Inner Mongolia 010022, China.
| | - Tianzi Xu
- Chemistry and Environment Science College, Inner Mongolia Normal University, Inner Mongolia Key Laboratory of Green Catalysis, Hohhot, Inner Mongolia 010022, China.
| |
Collapse
|
2
|
Gingerysty NJ, Odame-Ankrah CA, Jordan N, Osthoff HD. Interference from HONO in the measurement of ambient air NO 2 via photolytic conversion and quantification of NO. J Environ Sci (China) 2021; 107:184-193. [PMID: 34412781 DOI: 10.1016/j.jes.2020.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 06/13/2023]
Abstract
The reference method to quantify mixing ratios of the criteria air pollutant nitrogen dioxide (NO2) is NO-O3 chemiluminescence (CL), in which mixing ratios of nitric oxide (NO) are measured by sampling ambient air directly, and mixing ratios of NOx (= sum of NO and NO2) are measured by converting NO2 to NO using, for example, heated molybdenum catalyst or, more selectively, photolytic conversion (P-CL). In this work, the nitrous acid (HONO) interference in the measurement of NO2 by P-CL was investigated. Results with two photolytic NO2 converters are presented. The first used radiation centered at 395 nm, a wavelength region commonly utilized in P-CL. The second used light at 415 nm, where the overlap with the HONO absorption spectrum and hence its photolysis rate are less. Mixing ratios of NO2, NOx and HONO entering and exiting the converters were quantified by Thermal Dissociation Cavity Ring-down Spectroscopy (TD-CRDS). Both converters exhibited high NO2 conversion efficiency (CFNO2; > 90%) and partial conversion of HONO. Plots of CF against flow rate were consistent with photolysis frequencies of 4.2 s-1 and 2.9 s-1 for NO2 and 0.25 s-1 and 0.10 s-1 for HONO at 395 nm and 415 nm, respectively. CFHONO was larger than predicted from the overlap of the emission and HONO absorption spectra. The results imply that measurements of NO2 by P-CL marginally but systematically overestimate true NO2 concentrations, and that this interference should be considered in environments with high HONO:NO2 ratios such as the marine boundary layer or in biomass burning plumes.
Collapse
Affiliation(s)
| | | | - Nick Jordan
- Department of Chemistry, University of Calgary, Calgary AB T2N 1N4, Canada
| | - Hans D Osthoff
- Department of Chemistry, University of Calgary, Calgary AB T2N 1N4, Canada.
| |
Collapse
|
3
|
Liu J, Liang D, Liu L, Ning A, Zhang X. Catalytic sulfate formation mechanism influenced by important constituents of cloud water via the reaction of SO 2 oxidized by hypobromic acid in marine areas. Phys Chem Chem Phys 2021; 23:15935-15949. [PMID: 34296723 DOI: 10.1039/d1cp01981c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Comprehensive investigations of the possible formation pathways of sulfate, the main composition of atmospheric aerosol in marine areas, continue to challenge atmospheric chemists. As one of the most important oxidation routes of S(iv) contributing to sulfate formation, the reaction process of S(iv) oxidized by hypobromic acid, which is ubiquitous with the gas-phase mixing ratios of ∼310 ppt and has a well-known oxidative capacity, has attracted wide attention. However, little information is available about the detailed reaction mechanism. Especially, due to the abundant species in cloud water, the potential effect of these compositions on these reaction processes and the corresponding effect mechanism are also uncertain. Using high-level quantum chemical calculations, we theoretically elucidate the two-step mechanism of Br+ transfer proposed by experiment through the verification of the key BrSO3- intermediate formation and subsequent hydrolysis reaction or the uncovered reaction of BrSO3- intermediate with OH-. Further, the novel and more competitive mechanisms (OH+ or O atom transfer pathways) that have not been considered in previous studies, leading to sulfate formation directly, have been found. Furthermore, it should be mentioned that we revealed the effect mechanism of constituents catalyzed in cloud water, especially the important H2O-catalyzed mechanism. In addition, all the above pathways follow this catalytic mechanism. This finding indicates a linkage between the complex nature of the atmospheric constituents and related atmospheric reaction, as well as the enhanced occurrence of atmospheric secondary sulfate formation in the atmosphere. Hence, this exploration of sulfate formation related to hypobromic acid could provide a better understanding about the sources of sulfate in marine areas.
Collapse
Affiliation(s)
- Jiarong Liu
- Key Laboratory of Cluster Science, Ministry of Education of China, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China.
| | | | | | | | | |
Collapse
|
4
|
Li W, Shang Y, Ning H, Li J, Luo SN. Reaction pathways and kinetics study on a syngas combustion system: CO + HO 2 in an H 2O environment. Phys Chem Chem Phys 2020; 22:5797-5806. [PMID: 32105282 DOI: 10.1039/c9cp06642j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The reaction between CO and HO2 plays a significant role in syngas combustion. In this work, the catalytic effect of single-molecule water on this reaction is theoretically investigated at the CCSD(T)/aug-cc-pV(D,T,Q)Z and CCSD(T)-F12a/jun-cc-pVTZ levels in combination with the M062X/aug-cc-pVTZ level. Firstly, the potential energy surface (PES) of CO + HO2 (water-free) is revisited. The major products CO2 + OH are formed via a cis- or a trans-transition state (TS) channel and the formation of HCO + O2 is minor. In the presence of water, the title reaction has three different pre-reactive complexes (i.e., RC2: COHO2 + H2O, RC3: COH2O + HO2, and RC4: HO2H2O + CO), depending on the initial hydrogen bond formation. Compared to the water-free process, the reaction barriers of the water-assisted process are reduced considerably, due to more stable cyclic TSs and complexes. The rate constants for the bimolecular reaction pathways CO + HO2, RC2, RC3, and RC4 are further calculated using conventional transition state theory (TST) with Eckart asymmetric tunneling correction. For reaction CO + HO2, our calculations are in good agreement with the literature. In addition, the effective rate constants for the water-assisted process decrease by 1-2 orders of magnitude compared to the water-free one at a temperature below 600 K. In particular, the effective rate constants for the water-assisted and water-free processes are 1.55 × 10-28 and 3.86 × 10-26 cm3 molecule-1 s-1 at 300 K, respectively. This implies that the contribution of a single molecule water-assisted process is small and cannot accelerate the title reaction.
Collapse
Affiliation(s)
- Wenrui Li
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, and Institute of Material Dynamics, Southwest Jiaotong University, Chengdu, Sichuan 610031, P. R. China. and School of Chemistry and Chemical Engineering & Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing 401331, China.
| | - Yanlei Shang
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, and Institute of Material Dynamics, Southwest Jiaotong University, Chengdu, Sichuan 610031, P. R. China.
| | - Hongbo Ning
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, and Institute of Material Dynamics, Southwest Jiaotong University, Chengdu, Sichuan 610031, P. R. China.
| | - Jun Li
- School of Chemistry and Chemical Engineering & Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing 401331, China.
| | - Sheng-Nian Luo
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, and Institute of Material Dynamics, Southwest Jiaotong University, Chengdu, Sichuan 610031, P. R. China. and The Peac Institute of Multiscale Sciences, Chengdu, Sichuan 610031, P. R. China
| |
Collapse
|