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Yuan Z, Ma W, Zhu N, Zhu Y, Wu S, Lou Z. Identifying the fate of nitrogenous species during sewage sludge pyrolysis via in-situ tracing of protein-sludge inherent components interactions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160437. [PMID: 36427709 DOI: 10.1016/j.scitotenv.2022.160437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 11/10/2022] [Accepted: 11/19/2022] [Indexed: 06/16/2023]
Abstract
The effect of interactions between different components in sewage sludge on the thermochemical transformation of nitrogenous species is usually neglected, which is important to explain the generation mechanism of some key nitrogenous by-products. Here, we investigated the distribution, form, and chemical properties of the products from sludge-extracted protein (PR) under different pyrolysis scenarios using several in-situ probe techniques, to elucidate the critical role of typical sludge organics/inorganics on the evolution of nitrogenous intermediates and by-products. The results suggested that Ca/Fe/Si/Al-containing inorganics significantly affected the pyrolytic behavior of PR and the thermal transformation of nitrogenous species, while sludge organics, including humic acids and polysaccharides, had limited effects on the temperature-dependent evolution of nitrogenous species in PR. Among them, calcium oxide catalyzed the ring-opening reaction of heterocyclic-N with aromatic-like structures, resulting in a 21.1 %-68.8 % reduction in nitrogen fixation efficiency in the char. At lower temperatures (350-450 °C), calcium oxide caused more nitrogen to be transferred to the gas/tar phases in the form of NH3 and heterocyclic-N, and it also enhanced the conversion of nitrile-N → HCN → NO at temperatures above 450 °C. In contrast, polyferric salts inhibited the devolatilization of mono-heterocyclic-N and enhanced the thermal stability of poly-heterocyclic-N, resulting in a maximum increase of 18.5 mg·g-1 of nitrogen content in the char, while reducing the release of NH3 and HCN by 71.1 % and 32.0 %. This work elucidated the interaction between PR and inherent components in sludge, providing key information for the control of nitrogenous volatiles and NOx.
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Affiliation(s)
- Zhihang Yuan
- Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Wenchao Ma
- School of Environmental Science and Engineering, Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin University, Tianjin 300072, China
| | - Nanwen Zhu
- Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Ying Zhu
- Advanced Materials Institute, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250014, China
| | - Shaolin Wu
- Shanghai Solid Waste Management Center, Shanghai 200235, China
| | - Ziyang Lou
- Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; China Institute for Urban Governance, Shanghai Jiao Tong University, Shanghai 200240, China.
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2
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Pan Z, Bodi A, van Bokhoven JA, Hemberger P. Operando PEPICO unveils the catalytic fast pyrolysis mechanism of the three methoxyphenol isomers. Phys Chem Chem Phys 2022; 24:21786-21793. [PMID: 36082786 PMCID: PMC9491049 DOI: 10.1039/d2cp02741k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The development of lignin valorization processes such as catalytic fast pyrolysis (CFP) to produce fine chemicals and fuels leads to a more sustainable future. The implementation of CFP is enabled by understanding the chemistry of lignin constituents, which, however, requires thorough mechanistic investigations by detecting reactive species. In this contribution, we investigate the CFP of the three methoxyphenol (MP) isomers over H-ZSM-5 utilizing vacuum ultraviolet synchrotron radiation and operando photoelectron photoion coincidence (PEPICO) spectroscopy. All isomers demethylate at first to yield benzenediols, from which dehydroxylation reactions proceed to produce phenol and benzene. Additional pathways to form benzene proceed over cyclopentadiene, methylcyclopentadiene, and fulvene intermediates. The detection of trace amounts of methanol in the product stream suggests a demethoxylation reaction to yield phenol. Guaiacol (2- or ortho-MP) exhibits slightly higher reactivity compared to 3-MP and 4-MP, due to the formation of the fulvenone ketene, which opens additional routes to benzene and phenol. When compared to benzenediol catalytic pyrolysis, the additional methyl group in MP leads to high conversion at lower reactor temperatures, which is mostly owed to the lower H3C–O vs. H–O bond energy and the possibility to demethoxylate to produce phenol. Demethylation, demethoxylation and fulvenone ketene formation determine the reactivity of methoxyphenols over H-ZSM-5 to yield phenols, benzene and toluene. Intermediates are isomer-selectively detected utilizing threshold photoelectron spectroscopy.![]()
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Affiliation(s)
- Zeyou Pan
- Paul Scherrer Institute, 5232 Villigen, Switzerland. .,Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Andras Bodi
- Paul Scherrer Institute, 5232 Villigen, Switzerland.
| | - Jeroen A van Bokhoven
- Paul Scherrer Institute, 5232 Villigen, Switzerland. .,Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
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3
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Fan Y, Zhang Z, Wang Z, Yu H, Kong X, Li P, Li M, Xiao R, Liu C. Radical footprinting and regularity revealing during the pyrolysis of technical lignins. BIORESOURCE TECHNOLOGY 2022; 360:127648. [PMID: 35868468 DOI: 10.1016/j.biortech.2022.127648] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Revealing radical-mediated reactions is conducive to illustrate lignin pyrolysis and achieve subsequent regulation. Three technical lignins (hot-water-extracted lignin, kraft lignin, and soda lignin) were selected in this study and pyrolyzed from 400 °C to 700 °C, and their pyrolysis radicals in both chars and bio-oils were monitored with the electron paramagnetic resonance spectrometer. Results showed that spin concentrations of char radicals had a volcanic trend against the pyrolysis temperature, and reached the maximum values at 550-600 °C. However, the contents of bio-oil radicals were low during pyrolysis at low and medium temperature, but their spin concentrations exploded abruptly over 600-650 °C. Meanwhile, the bio-oil yields were found to drop after 550-600 °C, and the three inflection temperatures for char radicals, bio-oil radicals, and bio-oil yields were perfectly matched. These findings systematically elucidated the radical regularity in technical lignin pyrolysis and fundamentally contributed to the development of radical-mediated lignin pyrolysis mechanisms.
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Affiliation(s)
- Yuyang Fan
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Zhengxue Zhang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Zijun Wang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Haoyang Yu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Xiangchen Kong
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Peijun Li
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Ming Li
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Rui Xiao
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China
| | - Chao Liu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China.
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Zhu L, Cui C, Liu H, Zhou Z, Qi F. Thermochemical depolymerization of lignin: Process analysis with state-of-the-art soft ionization mass spectrometry. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.982126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Lignin valorization via thermochemical approaches has the potential to produce renewable fuels and value-added chemicals, which are of great significance to the sustainable development of human beings. During the thermochemical depolymerization which involves acid-catalyzed, alkali-catalyzed, oxidative, reductive, pyrolytic, and other reactions, the lignin structure will undergo a series of bond cleavage, condensation, and functional group changes, while the mechanism is still unclear. To improve the efficiency, the analysis of the evolution of intermediates during depolymerization is very important, among which soft ionization mass spectrometry plays a vital role. This review aims to summarize the research progress of process analysis of lignin depolymerization in both gas-phase, typically thermal and catalytic pyrolysis, and liquid-phase via online mass spectrometry. The challenges and our insights into the future development of the lignin valorization as well as soft ionization mass spectrometry methods are also discussed.
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Zhou H, Lin W, Chen C, Liu C, Wu J, Wang J, Fu J. Anchoring Effect of Organosilanes on Hierarchical ZSM-5 Zeolite for Catalytic Fast Pyrolysis of Cellulose to Aromatics. ACS OMEGA 2022; 7:15870-15879. [PMID: 35571774 PMCID: PMC9097197 DOI: 10.1021/acsomega.2c00983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/15/2022] [Indexed: 06/15/2023]
Abstract
As an essential chemical feedstock, aromatics can be obtained from biomass by catalytic fast pyrolysis (CFP) technology, in which diffusion limitation is still a problem. In this study, several ZSM-5 zeolites with intercrystal stacking macropores were synthesized by adding organosilanes (OSAs) with different alkyl chain groups. Due to the structure-directing effect of the OSA, the prepared ZSM-5 zeolites possess a larger external surface area and pore volume than Blank-Z5. Moreover, the pore size is related to the extent of anchoring of the OSA and silicon-aluminum species in the zeolite precursor. Pyridine Fourier transform infrared (Py-FTIR) and NH3-temperature-programmed desorption (TPD) analyses show that the obtained ZSM-5 zeolites have a higher Brønsted acidity and total number of acid sites. In addition, excessive addition of OSA is not conducive to the growth of ZSM-5 zeolites. The catalytic performance of the synthesized ZSM-5 zeolites was evaluated by Py-GC/MS. The larger external surface area and pore volume improve the accessibility of the acid sites and thus promote the conversion of biomass into aromatics.
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Affiliation(s)
- Huan Zhou
- Key
Laboratory of Biomass Chemical Engineering of Ministry of Education,
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Wenwen Lin
- Key
Laboratory of Biomass Chemical Engineering of Ministry of Education,
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Chao Chen
- Key
Laboratory of Biomass Chemical Engineering of Ministry of Education,
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
- Institute
of Zhejiang University—Quzhou, 78 Jiuhua Boulevard North, Quzhou 324000, China
| | - Chuang Liu
- State
Key Laboratory of Green Chemical Engineering and Industrial Catalysis, Sinopec Shanghai Research Institute of Petrochemical
Technology, 1658 North Pudong Road, Shanghai 201208, China
| | - Jianghua Wu
- Institute
of Zhejiang University—Quzhou, 78 Jiuhua Boulevard North, Quzhou 324000, China
| | - Jianghao Wang
- Institute
of Zhejiang University—Quzhou, 78 Jiuhua Boulevard North, Quzhou 324000, China
| | - Jie Fu
- Key
Laboratory of Biomass Chemical Engineering of Ministry of Education,
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
- Institute
of Zhejiang University—Quzhou, 78 Jiuhua Boulevard North, Quzhou 324000, China
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He M, Sun Y, Han B. Green Carbon Science: Efficient Carbon Resource Processing, Utilization, and Recycling towards Carbon Neutrality. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202112835] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Mingyuan He
- Shanghai Key Laboratory of Green Chemistry & Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China
- Research Institute of Petrochem Processing, SINOPEC Beijing 100083 China
| | - Yuhan Sun
- Low Carbon Energy Conversion Center Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201203 China
- Shanghai Low Carbon Technology Innovation Platform Shanghai 210620 China
| | - Buxing Han
- Shanghai Key Laboratory of Green Chemistry & Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China
- Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
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7
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He M, Sun Y, Han B. Green Carbon Science: Efficient Carbon Resource Processing, Utilization, and Recycling Towards Carbon Neutrality. Angew Chem Int Ed Engl 2021; 61:e202112835. [PMID: 34919305 DOI: 10.1002/anie.202112835] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Indexed: 11/10/2022]
Abstract
Green carbon science is defined as "Study and optimization of the transformation of carbon containing compounds and the relevant processes involved in the entire carbon cycle from carbon resource processing, carbon energy utilization, and carbon recycling to use carbon resources efficiently and minimize the net CO2 emission." [1] Green carbon science is related closely to carbon neutrality, and the relevant fields have developed quickly in the last decade. In this Minireview, we proposed the concept of carbon energy index, and the recent progresses in petroleum refining, production of liquid fuels, chemicals, and materials using coal, methane, CO2, biomass, and waste plastics are highlighted in combination with green carbon science, and an outlook for these important fields is provided in the final section.
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Affiliation(s)
- Mingyuan He
- East China Normal University, Department of Chemistry, 200062, Shanghai, CHINA
| | - Yuhan Sun
- Chinese Academy of Sciences, Shanghai Advanced Research Institute, 201203, Shanghai, CHINA
| | - Buxing Han
- Chinese Academy of Sciences, Institute of Chemistry, Beiyijie number 2, Zhongguancun, 100190, Beijing, CHINA
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Cui C, Chen X, Liu C, Zhu Y, Zhu L, Ouyang J, Shen Y, Zhou Z, Qi F. In Situ Reactor-Integrated Electrospray Ionization Mass Spectrometry for Heterogeneous Catalytic Reactions and Its Application in the Process Analysis of High-Pressure Liquid-Phase Lignin Depolymerization. Anal Chem 2021; 93:12987-12994. [PMID: 34520172 DOI: 10.1021/acs.analchem.1c02710] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Process analysis of heterogeneous catalytic reactions such as lignin depolymerization is essential to understand the reaction mechanism at the molecular level, but it is always challenging due to harsh conditions. Herein, we report an operando process analysis strategy by combining a microbatch reactor with high-resolution mass spectrometry (MS) via a reactor-integrated electrospray ionization (R-ESI) technique. R-ESI-MS expands the applications of traditional in situ MS to a heterogeneous and high-pressure liquid-phase system. With this strategy, we present the evolution of a series of monomers, dimers, and oligomers during lignin depolymerization under operando conditions (methanol solvent, 260 °C, ∼8 MPa), which is the first experimental elucidation of a progressive depolymerization pathway and evidence of repolymerization of active monomers. The proposed R-ESI-MS is crucial in probing depolymerization intermediates of lignin; it also provides a flexible strategy for process analysis of heterogeneous catalytic reactions under operando conditions.
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Affiliation(s)
- Cunhao Cui
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Xiamin Chen
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Chunjiang Liu
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Yanan Zhu
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Linyu Zhu
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Jianfeng Ouyang
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Yang Shen
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Zhongyue Zhou
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
| | - Fei Qi
- School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China
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Ren XY, Cao JP, Li Y, He ZM, Zhao XY, Liu TL, Feng XB, Zhao YP, Bai HC, Zhang J, Zhao SX. Formation of Light Aromatics and Coke during Catalytic Reforming of Biopolymer-Derived Volatiles over HZSM-5. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c01832] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xue-Yu Ren
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Jing-Pei Cao
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
- State Key Laboratory of High-Efficient Utilization of Coal and Green Chemical Engineering, Ningxia University, Yinchuan 750021, Ningxia, China
| | - Yang Li
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Zi-Meng He
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Xiao-Yan Zhao
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Tian-Long Liu
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Xiao-Bo Feng
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Yun-Peng Zhao
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Hong-Cun Bai
- State Key Laboratory of High-Efficient Utilization of Coal and Green Chemical Engineering, Ningxia University, Yinchuan 750021, Ningxia, China
| | - Ji Zhang
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
| | - Shi-Xuan Zhao
- Jiangsu Province Engineering Research Center of Fine Utilization of Carbon Resources, China University of Mining & Technology, Xuzhou 221116, Jiangsu, China
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Pan Z, Puente-Urbina A, Bodi A, van Bokhoven JA, Hemberger P. Isomer-dependent catalytic pyrolysis mechanism of the lignin model compounds catechol, resorcinol and hydroquinone. Chem Sci 2021; 12:3161-3169. [PMID: 34164083 PMCID: PMC8179379 DOI: 10.1039/d1sc00654a] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 02/05/2021] [Indexed: 12/26/2022] Open
Abstract
The catalytic pyrolysis mechanism of the initial lignin depolymerization products will help us develop biomass valorization strategies. How does isomerism influence reactivity, product formation, selectivities, and side reactions? By using imaging photoelectron photoion coincidence (iPEPICO) spectroscopy with synchrotron radiation, we reveal initial, short-lived reactive intermediates driving benzenediol catalytic pyrolysis over H-ZSM-5 catalyst. The detailed reaction mechanism unveils new pathways leading to the most important products and intermediates. Thanks to the two vicinal hydroxyl groups, catechol (o-benzenediol) is readily dehydrated to form fulvenone, a reactive ketene intermediate, and exhibits the highest reactivity. Fulvenone is hydrogenated on the catalyst surface to phenol or is decarbonylated to produce cyclopentadiene. Hydroquinone (p-benzenediol) mostly dehydrogenates to produce p-benzoquinone. Resorcinol, m-benzenediol, is the most stable isomer, because dehydration and dehydrogenation both involve biradicals owing to the meta position of the hydroxyl groups and are unfavorable. The three isomers may also interconvert in a minor reaction channel, which yields small amounts of cyclopentadiene and phenol via dehydroxylation and decarbonylation. We propose a generalized reaction mechanism for benzenediols in lignin catalytic pyrolysis and provide detailed mechanistic insights on how isomerism influences conversion and product formation. The mechanism accounts for processes ranging from decomposition reactions to molecular growth by initial polycyclic aromatic hydrocarbon (PAH) formation steps to yield, e.g., naphthalene. The latter involves a Diels-Alder dimerization of cyclopentadiene, isomerization, and dehydrogenation.
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Affiliation(s)
- Zeyou Pan
- Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute 5232 Villigen Switzerland
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich 8093 Zurich Switzerland
| | - Allen Puente-Urbina
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich 8093 Zurich Switzerland
| | - Andras Bodi
- Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute 5232 Villigen Switzerland
| | - Jeroen A van Bokhoven
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich 8093 Zurich Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute 5232 Villigen Switzerland
| | - Patrick Hemberger
- Laboratory for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute 5232 Villigen Switzerland
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