Journal of Analytical and Applied Pyrolysis最新文献

Experimental and ReaxFF MD study on the thermo-oxidative behavior of polyether ether ketone

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-21 DOI: 10.1016/j.jaap.2025.107141

Chuan Ma , Guoqing Huang , Shogo Kumagai , Masumi Sato , Yuko Saito , Atsushi Watanabe , Chuichi Watanabe , Norio Teramae , Toshiaki Yoshioka

Polyether ether ketone (PEEK) is a suitable thermoplastic matrix for composite materials in various industrial applications. Thermal treatment presents a promising approach for recycling high-performance engineering plastics through the recovery of valuable byproducts. This study investigated the thermo-oxidative behavior of PEEK using thermogravimetric analysis (TGA) and a customized pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) system to perform real-time analysis under oxidative atmospheres. Reactive force field molecular dynamics (ReaxFF-MD) simulations were employed to explore its chemical degradation mechanisms. TGA revealed that the initial degradation of PEEK occurred above 540 °C, highlighting its exceptional thermal stability. Oxygen lowered the degradation temperature by approximately 20 °C, leading to a distinct two-stage process. Notably, chemical structure changes were observed below 500 °C, consistent with ReaxFF-MD findings indicating oligomer formation first through main chain cleavage. Py-GC/MS analysis showed that PEEK pyrolysis generated valuable phenolic compounds, primarily phenol and p-phenoxyphenol. Dibenzofuran, along with significant production of CO₂/CO and H₂O were the predominant oxidation products. Py-GC/MS and ReaxFF-MD combined demonstrated that ether and ketone groups cleaved initially, with terminal phenylene-carbonyl radicals breaking more readily than phenoxy radicals, resulting in early CO release. Aryloxy radicals underwent chain cleavage, hydrogen abstraction, and hydrogen transfer reactions to form various phenolics. Oxygen attacked the main chains to form •HO₂ and •OH radicals, which subsequently reacted with terminal rings through hydrogenation and hydrodeoxygenation. Ultimately, ring-opening reactions converted intermediates into CO₂, CO, and H₂O. These results offer insights into the thermo-oxidative behavior of PEEK and suggest potential for recovering high-value chemicals from waste PEEK composites.

{"title":"Experimental and ReaxFF MD study on the thermo-oxidative behavior of polyether ether ketone","authors":"Chuan Ma , Guoqing Huang , Shogo Kumagai , Masumi Sato , Yuko Saito , Atsushi Watanabe , Chuichi Watanabe , Norio Teramae , Toshiaki Yoshioka","doi":"10.1016/j.jaap.2025.107141","DOIUrl":"10.1016/j.jaap.2025.107141","url":null,"abstract":"<div><div>Polyether ether ketone (PEEK) is a suitable thermoplastic matrix for composite materials in various industrial applications. Thermal treatment presents a promising approach for recycling high-performance engineering plastics through the recovery of valuable byproducts. This study investigated the thermo-oxidative behavior of PEEK using thermogravimetric analysis (TGA) and a customized pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) system to perform real-time analysis under oxidative atmospheres. Reactive force field molecular dynamics (ReaxFF-MD) simulations were employed to explore its chemical degradation mechanisms. TGA revealed that the initial degradation of PEEK occurred above 540 °C, highlighting its exceptional thermal stability. Oxygen lowered the degradation temperature by approximately 20 °C, leading to a distinct two-stage process. Notably, chemical structure changes were observed below 500 °C, consistent with ReaxFF-MD findings indicating oligomer formation first through main chain cleavage. Py-GC/MS analysis showed that PEEK pyrolysis generated valuable phenolic compounds, primarily phenol and <em>p</em>-phenoxyphenol. Dibenzofuran, along with significant production of CO<sub>2</sub>/CO and H<sub>2</sub>O were the predominant oxidation products. Py-GC/MS and ReaxFF-MD combined demonstrated that ether and ketone groups cleaved initially, with terminal phenylene-carbonyl radicals breaking more readily than phenoxy radicals, resulting in early CO release. Aryloxy radicals underwent chain cleavage, hydrogen abstraction, and hydrogen transfer reactions to form various phenolics. Oxygen attacked the main chains to form •HO<sub>2</sub> and •OH radicals, which subsequently reacted with terminal rings through hydrogenation and hydrodeoxygenation. Ultimately, ring-opening reactions converted intermediates into CO<sub>2</sub>, CO, and H<sub>2</sub>O. These results offer insights into the thermo-oxidative behavior of PEEK and suggest potential for recovering high-value chemicals from waste PEEK composites.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107141"},"PeriodicalIF":5.8,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhancing the reactivity and combustion efficiency of Al@AP by precise catalysis of MoO3-x quantum dots with oxygen vacancy

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-21 DOI: 10.1016/j.jaap.2025.107142

Xin Li , Ruixuan Xu , Hao Zhang , Heng Deng , Qi-Long Yan , Hongqi Nie

Aluminum (Al) can significantly improve the energy density and specific impulse (I_sp) of solid rocket propellants as the primary metal fuel, but its incomplete combustion results in an undesirable energy release performance. The strategy of fuel/oxidizer interfacial control has been proved to effectively enhance the reaction efficiency of Al-based composites and thus improving the combustion properties of solid propellants. Ammonium perchlorate (AP) is commonly used as a high-energy oxidizer in solid propellant, and its thermal decomposition behavior directly affects the combustion characteristics of propellants. The addition of combustion catalysts can decrease thermal decomposition temperature and increase thermal reactivity of AP. As an emerging catalytic material, MoO_3-x quantum dots (QDs) with oxygen vacancies possess a high specific surface and strong charge adsorption capacity, which renders it a great potential for catalyzing AP. In this study, MoO_3-x QDs were introduced as catalyst and compared with traditional nano-metal oxides (M_xO_y), the spherical Al@AP/M_xO_y composites with polydopamine as interfacial layer were prepared by spray drying method. The particle morphology, thermal decomposition kinetics and ignition properties of Al@AP/M_xO_y were investigated. The phase composition, morphology and particle size distribution for the condensed combustion products of composites were further analyzed. The decreased particle size and less unreacted Al content in CCPs indicated the increase of combustion efficiency between Al and AP. In particular, Al@AP/MoO_3-x has the higher heat of reaction, lower thermal decomposition temperature and small CCPs particle size distribution, which collectively suggested that the MoO_3-x is capable to improve the thermal reactivity of Al@AP composites with a higher combustion efficiency.

{"title":"Enhancing the reactivity and combustion efficiency of Al@AP by precise catalysis of MoO3-x quantum dots with oxygen vacancy","authors":"Xin Li , Ruixuan Xu , Hao Zhang , Heng Deng , Qi-Long Yan , Hongqi Nie","doi":"10.1016/j.jaap.2025.107142","DOIUrl":"10.1016/j.jaap.2025.107142","url":null,"abstract":"<div><div>Aluminum (Al) can significantly improve the energy density and specific impulse (I<sub>sp</sub>) of solid rocket propellants as the primary metal fuel, but its incomplete combustion results in an undesirable energy release performance. The strategy of fuel/oxidizer interfacial control has been proved to effectively enhance the reaction efficiency of Al-based composites and thus improving the combustion properties of solid propellants. Ammonium perchlorate (AP) is commonly used as a high-energy oxidizer in solid propellant, and its thermal decomposition behavior directly affects the combustion characteristics of propellants. The addition of combustion catalysts can decrease thermal decomposition temperature and increase thermal reactivity of AP. As an emerging catalytic material, MoO<sub>3-x</sub> quantum dots (QDs) with oxygen vacancies possess a high specific surface and strong charge adsorption capacity, which renders it a great potential for catalyzing AP. In this study, MoO<sub>3-x</sub> QDs were introduced as catalyst and compared with traditional nano-metal oxides (M<sub>x</sub>O<sub>y</sub>), the spherical Al@AP/M<sub>x</sub>O<sub>y</sub> composites with polydopamine as interfacial layer were prepared by spray drying method. The particle morphology, thermal decomposition kinetics and ignition properties of Al@AP/M<sub>x</sub>O<sub>y</sub> were investigated. The phase composition, morphology and particle size distribution for the condensed combustion products of composites were further analyzed. The decreased particle size and less unreacted Al content in CCPs indicated the increase of combustion efficiency between Al and AP. In particular, Al@AP/MoO<sub>3-x</sub> has the higher heat of reaction, lower thermal decomposition temperature and small CCPs particle size distribution, which collectively suggested that the MoO<sub>3-x</sub> is capable to improve the thermal reactivity of Al@AP composites with a higher combustion efficiency.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107142"},"PeriodicalIF":5.8,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unveiling atomic mechanism of organic sodium on the inhibition of tar and the release behavior of sodium in Zhundong coal hydropyrolysis via ReaxFF MD simulation

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-19 DOI: 10.1016/j.jaap.2025.107130

Xiaoling Wang , Shaoqing Wang , Yungang Zhao , Yan Shao , Ruifeng Mu , Juqing Liu , Haofan Su

In this work, the effect of organic Na on coal hydropyrolysis was investigated at the atomic level by reactive molecular dynamics (ReaxFF MD) simulation, and verified by corresponding hydropyrolysis experiment. Results show that organic Na can reduce the initial temperature of the hydropyrolysis reaction, promote the release of H₂O and volatile gases, and accelerate the decomposition of coal macromolecules. The atomic inhibition mechanism of organic Na on tar formation was revealed, through inhibiting the formation path of tar, promoting tar condensation to coke, and enhancing the release of H₂O and other volatiles in tar. Additionally, through statistical analysis of Na-containing products and tracking real-time reaction trajectories, three primary pathways for the migration and transformation of organic Na were identified. First, organic Na breaks at the O-Na bond to form atomic Na, which then reacts with inorganic components like H₂O and -OH, a process that occurs frequently. The resulting atomic Na combines with gaseous hydrocarbons to form gaseous Na, which is subsequently released. Tar-Na is formed when atomic Na interacts with tar molecules. These findings provided valuable molecular dynamics insights for exploring the sustainable and efficient conversion of high-alkali coal resources.

{"title":"Unveiling atomic mechanism of organic sodium on the inhibition of tar and the release behavior of sodium in Zhundong coal hydropyrolysis via ReaxFF MD simulation","authors":"Xiaoling Wang , Shaoqing Wang , Yungang Zhao , Yan Shao , Ruifeng Mu , Juqing Liu , Haofan Su","doi":"10.1016/j.jaap.2025.107130","DOIUrl":"10.1016/j.jaap.2025.107130","url":null,"abstract":"<div><div>In this work, the effect of organic Na on coal hydropyrolysis was investigated at the atomic level by reactive molecular dynamics (ReaxFF MD) simulation, and verified by corresponding hydropyrolysis experiment. Results show that organic Na can reduce the initial temperature of the hydropyrolysis reaction, promote the release of H<sub>2</sub>O and volatile gases, and accelerate the decomposition of coal macromolecules. The atomic inhibition mechanism of organic Na on tar formation was revealed, through inhibiting the formation path of tar, promoting tar condensation to coke, and enhancing the release of H<sub>2</sub>O and other volatiles in tar. Additionally, through statistical analysis of Na-containing products and tracking real-time reaction trajectories, three primary pathways for the migration and transformation of organic Na were identified. First, organic Na breaks at the O-Na bond to form atomic Na, which then reacts with inorganic components like H₂O and -OH, a process that occurs frequently. The resulting atomic Na combines with gaseous hydrocarbons to form gaseous Na, which is subsequently released. Tar-Na is formed when atomic Na interacts with tar molecules. These findings provided valuable molecular dynamics insights for exploring the sustainable and efficient conversion of high-alkali coal resources.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107130"},"PeriodicalIF":5.8,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Degradation mechanism of decabromodiphenyl ether: Reaction with reactive radicals and formation chemistry of polybrominated dibenzo-p-dioxins and dibenzofurans

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-17 DOI: 10.1016/j.jaap.2025.107139

Yang Long , Liming Tai , Shi Yan , Yan Zhu , Jinbao Huang , Li Jin , Yaqing Cai , Hong Wang , Xinsheng Li , Hao Cheng

Although decabromodiphenyl ether (BDE-209) has been banned from production and use as a brominated flame retardant, its threat to human and ecological environment cannot still be ignored. Nevertheless, the mechanism of BDE-209 initiated by reactive radicals in the thermochemical decomposition process remains unknown. The density functional theory method is used to study the thermochemical decomposition behavior of BDE-209, with reactive radical reactions, and the formation mechanism of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs). The results show that BDE-209 is not prone to self-decomposition due to its high bond dissociation energy (249.6 ∼ 281.4 kJ/mol) and HOMO-LUMO energy gap (7.10 eV). The reaction of BDE-209 with three active free radicals, including •H, Br•, and •OH, usually results in a variety of hypobromated products or important intermediates at low reaction energy barriers (52.9, 54.3, 50.4 kJ/mol). At 600 K, the branching ratio of H-abstraction reaction in the reaction system of •H and BDE-209 is 67.5 %. At 300 K, the reaction rate constant of BDE-209 with Br• to form P2 and IM2 is 4.14 × 10⁻¹⁷ cm³ molecule⁻¹ s⁻¹. The branching ratio of BDE-209 + •OH → P9 + Br• is 40.3 % at 400 K. The OH-addition and OH-abstraction reactions of BDE-209 form octabromodibenzo-p-dioxin, which is further debrominated to form PBDDs. Ortho-phenyl-type radical generated by eliminating ortho-Br is a crucial precursor radical for the formation of PBDD/Fs. The most favorable reaction pathway for the subsequent degradation of ortho-phenyl-type radical is IM10 → TS38 → IM13. The participation of polymer materials increases the production of toxic PBDD/Fs. This is because the free radicals formed by the chain scission of the polymer can easily extract the ortho-Br atom of BDE-209, thereby promoting the formation of the precursor (ortho-phenyl radical) of PBDD/Fs. Furthermore, the degradation mechanism of BDE-209 induced by active free radicals is explored to help control the formation of toxic substances during thermal treatment.

{"title":"Degradation mechanism of decabromodiphenyl ether: Reaction with reactive radicals and formation chemistry of polybrominated dibenzo-p-dioxins and dibenzofurans","authors":"Yang Long , Liming Tai , Shi Yan , Yan Zhu , Jinbao Huang , Li Jin , Yaqing Cai , Hong Wang , Xinsheng Li , Hao Cheng","doi":"10.1016/j.jaap.2025.107139","DOIUrl":"10.1016/j.jaap.2025.107139","url":null,"abstract":"<div><div>Although decabromodiphenyl ether (BDE-209) has been banned from production and use as a brominated flame retardant, its threat to human and ecological environment cannot still be ignored. Nevertheless, the mechanism of BDE-209 initiated by reactive radicals in the thermochemical decomposition process remains unknown. The density functional theory method is used to study the thermochemical decomposition behavior of BDE-209, with reactive radical reactions, and the formation mechanism of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs). The results show that BDE-209 is not prone to self-decomposition due to its high bond dissociation energy (249.6 ∼ 281.4 kJ/mol) and HOMO-LUMO energy gap (7.10 eV). The reaction of BDE-209 with three active free radicals, including •H, Br•, and •OH, usually results in a variety of hypobromated products or important intermediates at low reaction energy barriers (52.9, 54.3, 50.4 kJ/mol). At 600 K, the branching ratio of H-abstraction reaction in the reaction system of •H and BDE-209 is 67.5 %. At 300 K, the reaction rate constant of BDE-209 with Br• to form P2 and IM2 is 4.14 × 10<sup>−17</sup> cm<sup>3</sup> molecule<sup>−1</sup> s<sup>−1</sup>. The branching ratio of BDE-209 + •OH → P9 + Br• is 40.3 % at 400 K. The OH-addition and OH-abstraction reactions of BDE-209 form octabromodibenzo-p-dioxin, which is further debrominated to form PBDDs. <em>Ortho</em>-phenyl-type radical generated by eliminating <em>ortho</em>-Br is a crucial precursor radical for the formation of PBDD/Fs. The most favorable reaction pathway for the subsequent degradation of <em>ortho</em>-phenyl-type radical is IM10 → <strong>TS38</strong> → IM13. The participation of polymer materials increases the production of toxic PBDD/Fs. This is because the free radicals formed by the chain scission of the polymer can easily extract the <em>ortho</em>-Br atom of BDE-209, thereby promoting the formation of the precursor (<em>ortho</em>-phenyl radical) of PBDD/Fs. Furthermore, the degradation mechanism of BDE-209 induced by active free radicals is explored to help control the formation of toxic substances during thermal treatment.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107139"},"PeriodicalIF":5.8,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143848650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of differential hydrocarbon expulsion on the characteristics of saturated and aromatic compounds during hydrous pyrolysis of organic-rich shale

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-17 DOI: 10.1016/j.jaap.2025.107138

Dongjun Song , Yifeng Hong , Jingyu Zhang , Jincai Tuo

Primary migration and expulsion of hydrocarbons from organic-rich shales can remarkably alter the group compositions of shale oil, while the impacts on specific molecular constituents are still unclear. Here, a lacustrine Chang-7 organic-rich shale sample from the Ordos Basin was subjected to semi-closed and closed pyrolysis, and the characteristics and ratios of commonly used saturated and aromatic constituents of the collected oil and rock extracts were discussed. The results indicated that low-molecular-weight (<C₂₀) normal alkanes and pristane (Pr) are preferentially expelled from the shale before oil-cracking stages. In contrast, high-molecular-weight normal alkanes and phytane (Ph) are retained within the shale due to the relatively more robust interactions with kerogen, and polarity dominantly affects the composition fractionation during the expulsion of aromatic compounds. This led to significant discrepancies in ratios of saturated and aromatic hydrocarbon compounds between the collected oil and rock extracts, such as (nC₂₁+nC₂₂)/(nC₂₈+nC₂₉), Pr/Ph, and indicators related to methylnaphthalene, methylphenanthrene, methyldibenzothiophene, and trifluorene series. Trends of those molecular ratios reverse due to intensive thermal cracking at higher maturities. The fractionation heavily affects the accuracy of maturity comparison of aromatic hydrocarbon ratios in shale source rocks and related hydrocarbon accumulations, ultimately casting doubts on oil-source correlations. Moreover, the fractionation can misguide inferences regarding paleoenvironmental conditions based on the trifluorene series and the ternary diagram of the Ph/nC₁₈, Pr/Ph, and Pr/nC₁₇. Finally, we propose that some proxies previously applied to maturity and paleoenvironmental evaluation can be used to indicate hydrocarbon expulsion.

{"title":"Effects of differential hydrocarbon expulsion on the characteristics of saturated and aromatic compounds during hydrous pyrolysis of organic-rich shale","authors":"Dongjun Song , Yifeng Hong , Jingyu Zhang , Jincai Tuo","doi":"10.1016/j.jaap.2025.107138","DOIUrl":"10.1016/j.jaap.2025.107138","url":null,"abstract":"<div><div>Primary migration and expulsion of hydrocarbons from organic-rich shales can remarkably alter the group compositions of shale oil, while the impacts on specific molecular constituents are still unclear. Here, a lacustrine Chang-7 organic-rich shale sample from the Ordos Basin was subjected to semi-closed and closed pyrolysis, and the characteristics and ratios of commonly used saturated and aromatic constituents of the collected oil and rock extracts were discussed. The results indicated that low-molecular-weight (<C<sub>20</sub>) normal alkanes and pristane (Pr) are preferentially expelled from the shale before oil-cracking stages. In contrast, high-molecular-weight normal alkanes and phytane (Ph) are retained within the shale due to the relatively more robust interactions with kerogen, and polarity dominantly affects the composition fractionation during the expulsion of aromatic compounds. This led to significant discrepancies in ratios of saturated and aromatic hydrocarbon compounds between the collected oil and rock extracts, such as (<em>n</em>C<sub>21</sub>+<em>n</em>C<sub>22</sub>)/(<em>n</em>C<sub>28</sub>+<em>n</em>C<sub>29</sub>), Pr/Ph, and indicators related to methylnaphthalene, methylphenanthrene, methyldibenzothiophene, and trifluorene series. Trends of those molecular ratios reverse due to intensive thermal cracking at higher maturities. The fractionation heavily affects the accuracy of maturity comparison of aromatic hydrocarbon ratios in shale source rocks and related hydrocarbon accumulations, ultimately casting doubts on oil-source correlations. Moreover, the fractionation can misguide inferences regarding paleoenvironmental conditions based on the trifluorene series and the ternary diagram of the Ph/<em>n</em>C<sub>18</sub>, Pr/Ph, and Pr/<em>n</em>C<sub>17</sub>. Finally, we propose that some proxies previously applied to maturity and paleoenvironmental evaluation can be used to indicate hydrocarbon expulsion.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107138"},"PeriodicalIF":5.8,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143848652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the biomass catalytic pyrolysis over hierarchically porous ZSM-5 catalyst derived from solid wastes by means of photoionization mass spectrometry

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-16 DOI: 10.1016/j.jaap.2025.107136

Ke Yang , Gang Wu , Bo Zhang , Liangyuan Jia , Huiyan Zhang

Catalytic fast pyrolysis (CFP) is one of the most efficient methods for directly converting biomass into green aromatics. Although ZSM-5 catalyst is efficient at producing aromatics, the catalyst deactivation brings challenge to industrial applications. Constructing additional mesoporous structure in ZSM-5 catalyst can overcome this drawback. In this study, two solid wastes are used as raw materials to synthesize hierarchically porous ZSM-5 catalyst based on solvent-free method, aligning with the target of “green chemistry”. Comparing with the commercial ZSM-5 catalyst, the synthesized catalyst achieves a higher BTX yield (benzene, toluene, and xylene), with increases of approximately 44 %, 7 %, and 12 %, respectively. The mesopore-to-micropore volume ratio is a key factor in determining catalytic efficiency. Moreover, PI-MS is used to monitor the deactivation behavior of catalyst online during the CFP process, showing that the synthesized catalyst has a slower deactivation rate. The hierarchically porous structure plays a crucial role in slowing the transformation of oxygenated coke into graphite-like coke, which is a major contributor to catalyst deactivation. This work can provide a green and convenient method for producing hierarchically porous ZSM-5 catalyst and be useful for improving the selectivity of aromatic compounds, offering a promising alternative to conventional ZSM-5 catalyst in industrial applications.

催化快速热解（CFP）是将生物质直接转化为绿色芳烃的最有效方法之一。虽然 ZSM-5 催化剂能高效生产芳烃，但催化剂失活给工业应用带来了挑战。在 ZSM-5 催化剂中构建额外的介孔结构可以克服这一缺点。本研究以两种固体废弃物为原料，采用无溶剂法合成了分层多孔的 ZSM-5 催化剂，实现了 "绿色化学 "的目标。与商用 ZSM-5 催化剂相比，合成的催化剂获得了更高的 BTX（苯、甲苯和二甲苯）产率，分别提高了约 44%、7% 和 12%。中孔与微孔的体积比是决定催化效率的关键因素。此外，PI-MS 被用于在线监测 CFP 过程中催化剂的失活行为，结果表明合成催化剂的失活速率较慢。分层多孔结构在减缓含氧焦炭转化为石墨样焦炭的过程中发挥了关键作用，而石墨样焦炭是导致催化剂失活的主要原因。这项工作为生产分层多孔 ZSM-5 催化剂提供了一种绿色、便捷的方法，可用于提高芳香族化合物的选择性，是传统 ZSM-5 催化剂在工业应用中的一种有前途的替代品。

{"title":"Study on the biomass catalytic pyrolysis over hierarchically porous ZSM-5 catalyst derived from solid wastes by means of photoionization mass spectrometry","authors":"Ke Yang , Gang Wu , Bo Zhang , Liangyuan Jia , Huiyan Zhang","doi":"10.1016/j.jaap.2025.107136","DOIUrl":"10.1016/j.jaap.2025.107136","url":null,"abstract":"<div><div>Catalytic fast pyrolysis (CFP) is one of the most efficient methods for directly converting biomass into green aromatics. Although ZSM-5 catalyst is efficient at producing aromatics, the catalyst deactivation brings challenge to industrial applications. Constructing additional mesoporous structure in ZSM-5 catalyst can overcome this drawback. In this study, two solid wastes are used as raw materials to synthesize hierarchically porous ZSM-5 catalyst based on solvent-free method, aligning with the target of “green chemistry”. Comparing with the commercial ZSM-5 catalyst, the synthesized catalyst achieves a higher BTX yield (benzene, toluene, and xylene), with increases of approximately 44 %, 7 %, and 12 %, respectively. The mesopore-to-micropore volume ratio is a key factor in determining catalytic efficiency. Moreover, PI-MS is used to monitor the deactivation behavior of catalyst online during the CFP process, showing that the synthesized catalyst has a slower deactivation rate. The hierarchically porous structure plays a crucial role in slowing the transformation of oxygenated coke into graphite-like coke, which is a major contributor to catalyst deactivation. This work can provide a green and convenient method for producing hierarchically porous ZSM-5 catalyst and be useful for improving the selectivity of aromatic compounds, offering a promising alternative to conventional ZSM-5 catalyst in industrial applications.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107136"},"PeriodicalIF":5.8,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143848649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Advancements in sludge pyrolysis: Integrated resource recovery and process-derived pollutant mitigation

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-16 DOI: 10.1016/j.jaap.2025.107137

Lijun Bai , Bing Wu , Jianglin Cao , Xiaohu Dai

Pyrolysis is an environmentally friendly technology with significant potential for sludge resource recovery and treatment. This review examines key factors influencing sludge pyrolysis, such as temperature, heating rate, and residence time, and their impacts on the yield and quality of pyrolysis products. The potential applications of these products are extensive, and their sustainability can be evaluated through energy balance analysis. Moreover, co-pyrolysis and catalytic pyrolysis are crucial in improving product quality and controlling pollutant emissions. Therefore, this review focuses on various co-pyrolysis materials and catalysts, highlighting their roles in enhancing product quality and elucidating the mechanisms underlying these improvements. Strategies for managing the release of nitrogen, sulfur, and heavy metal pollutants are also discussed. Finally, the review presents recent advancements in sludge pyrolysis and provides recommendations for future research to further enhance the technology and expand the applications of pyrolysis products.

热解是一种环境友好型技术，在污泥资源回收和处理方面潜力巨大。本综述探讨了影响污泥热解的关键因素，如温度、加热速率和停留时间，以及它们对热解产品产量和质量的影响。这些产品的潜在应用非常广泛，其可持续性可通过能量平衡分析进行评估。此外，共热解和催化热解对提高产品质量和控制污染物排放也至关重要。因此，本综述将重点介绍各种共热解材料和催化剂，突出它们在提高产品质量方面的作用，并阐明这些改进的内在机制。此外，还讨论了管理氮、硫和重金属污染物排放的策略。最后，综述介绍了污泥热解的最新进展，并为未来研究提出了建议，以进一步提高技术水平并扩大热解产品的应用范围。

引用次数: 0

Microwave-assisted pyrolysis of liquid hydrocarbons using iron-based alumina catalysts obtained by solution combustion synthesis: The effect of synthesis parameters

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-15 DOI: 10.1016/j.jaap.2025.107116

Zachary A. Chanoi, Laura A. Martinez-Espinoza, Evgeny Shafirovich

The microwave-absorbing and catalytic properties of iron-based alumina (FeAl_xO_y) materials have enabled their use as catalysts for the microwave-assisted generation of hydrogen and carbon via pyrolysis of hydrocarbons. Solution combustion synthesis (SCS) is a promising method to fabricate these materials, but the pyrolysis performance still needs to be improved. The present work investigated how altering the SCS parameters affects the pyrolysis of diesel fuel, gasoline, and crude oil. Two fuels (citric acid and glycine), four Fe:Al molar ratios, and two heating modes (hotplate and furnace) were tested. Fe/γ-Al₂O₃ and Fe/β-SiC catalysts were prepared via incipient wetness impregnation for comparison. Among the three fossil fuels tested, diesel fuel yielded the highest amounts of H₂ and least amounts of CO_x. The choice of fuel for the SCS process and the Fe/Al ratio strongly affected pyrolysis performance as they influence properties important for both catalysis and microwave absorption. The use of glycine resulted in catalysts that exhibited high H₂ yield and low CO₂ generation, which is explained by the revealed structural differences. The increase in the Fe:Al molar ratio accelerated microwave heating by adding more magnetic loss but also increased the amount of CO_x. When the optimal SCS parameters were used, FeAl_xO_y catalysts outperformed Fe/γ-Al₂O₃ and Fe/β-SiC. The high H₂ generation efficiency of the SCS catalysts is explained by their enhanced microwave-absorption properties. Scanning electron microscopy and energy dispersive X-ray spectroscopy revealed the formation of large-diameter CNTs via the tip-growth mechanism. The regeneration of SCS catalysts was demonstrated via the Boudouard reaction.

铁基氧化铝（FeAlxOy）材料的微波吸收和催化特性使其能够用作催化剂，在微波辅助下通过热解碳氢化合物产生氢气和碳。溶液燃烧合成（SCS）是制造这些材料的一种很有前景的方法，但其热解性能仍有待提高。本研究调查了改变溶液燃烧合成参数如何影响柴油、汽油和原油的热解。测试了两种燃料（柠檬酸和甘氨酸）、四种铁铝摩尔比和两种加热模式（热板和熔炉）。通过初湿浸渍法制备了 Fe/γ-Al2O3 和 Fe/β-SiC 催化剂，以进行比较。在测试的三种化石燃料中，柴油产生的 H2 量最高，COx 量最低。选择用于 SCS 工艺的燃料和铁/铝比例对热解性能有很大影响，因为它们会影响对催化和微波吸收都很重要的特性。甘氨酸的使用导致催化剂表现出较高的 H2 产率和较低的 CO2 生成量，这可以用所揭示的结构差异来解释。铁：铝摩尔比的增加增加了磁损耗，从而加速了微波加热，但同时也增加了二氧化碳的生成量。在使用最佳 SCS 参数时，FeAlxOy 催化剂的性能优于 Fe/γ-Al2O3 和 Fe/β-SiC。SCS 催化剂较高的 H2 生成效率得益于其增强的微波吸收特性。扫描电子显微镜和能量色散 X 射线光谱显示，大直径 CNT 是通过尖端生长机制形成的。通过 Boudouard 反应证明了 SCS 催化剂的再生能力。

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引用次数: 0

Wolframite MgWO4-derived Ni-based catalysts for auto-thermal reforming of acetic acid with high anti-coking properties

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-14 DOI: 10.1016/j.jaap.2025.107134

Yali Tan , Fangqiao Pang , Mao Gan , Ying Su , Jinbo Liu , Lihong Huang

Auto-thermal reforming (ATR) process is effective in converting biomass-derived acetic acid (HAc) for hydrogen production, and provides a clean, carbon-neutral approach for green hydrogen supply. However, challenges, such as catalytic deactivation by carbon deposition, sintering of active components, and oxidation, need to be addressed. Therefore, monoclinic wolframite-type Ni/MgWO₄ catalysts were prepared by the Pechini method and applied in ATR for H₂ production. The results indicated that with doping of Mg species in tungsten oxide, mixed phases of monoclinic wolframite-type m-MgWO₄ and tetragonal scheelite-type t-MgWO₄ were formed. During the ATR process, t-MgWO₄ transformed into the more stable m-MgWO₄, and thus the wolframite m-MgWO₄ existed as the main phase. The stability of m-MgWO₄ structure was beneficial for dispersing active component of Ni⁰ over the MgWO₄ support and restraining aggregation of Ni⁰ species. Furthermore, this transformation promoted formation of oxygen vacancies and enhancing lattice oxygen mobility for gasification of coke precursors. As a result, the Ni_0.80W_1.11Mg_2.02O_6.15±δ catalyst with Ni/m-MgWO₄ structure demonstrated high stability and activity during ATR test: the conversion rate of acetic acid and the H₂ yield remained stable at 100 % and 2.78 mol-H₂/mol-HAc, respectively, while no coking was found.

{"title":"Wolframite MgWO4-derived Ni-based catalysts for auto-thermal reforming of acetic acid with high anti-coking properties","authors":"Yali Tan , Fangqiao Pang , Mao Gan , Ying Su , Jinbo Liu , Lihong Huang","doi":"10.1016/j.jaap.2025.107134","DOIUrl":"10.1016/j.jaap.2025.107134","url":null,"abstract":"<div><div>Auto-thermal reforming (ATR) process is effective in converting biomass-derived acetic acid (HAc) for hydrogen production, and provides a clean, carbon-neutral approach for green hydrogen supply. However, challenges, such as catalytic deactivation by carbon deposition, sintering of active components, and oxidation, need to be addressed. Therefore, monoclinic wolframite-type Ni/MgWO<sub>4</sub> catalysts were prepared by the Pechini method and applied in ATR for H<sub>2</sub> production. The results indicated that with doping of Mg species in tungsten oxide, mixed phases of monoclinic wolframite-type m-MgWO<sub>4</sub> and tetragonal scheelite-type t-MgWO<sub>4</sub> were formed. During the ATR process, t-MgWO<sub>4</sub> transformed into the more stable m-MgWO<sub>4</sub>, and thus the wolframite m-MgWO<sub>4</sub> existed as the main phase. The stability of m-MgWO<sub>4</sub> structure was beneficial for dispersing active component of Ni<sup>0</sup> over the MgWO<sub>4</sub> support and restraining aggregation of Ni<sup>0</sup> species. Furthermore, this transformation promoted formation of oxygen vacancies and enhancing lattice oxygen mobility for gasification of coke precursors. As a result, the Ni<sub>0.80</sub>W<sub>1.11</sub>Mg<sub>2.02</sub>O<sub>6.15±δ</sub> catalyst with Ni/m-MgWO<sub>4</sub> structure demonstrated high stability and activity during ATR test: the conversion rate of acetic acid and the H<sub>2</sub> yield remained stable at 100 % and 2.78 mol-H<sub>2</sub>/mol-HAc, respectively, while no coking was found.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107134"},"PeriodicalIF":5.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of components interaction during pressurized pyrolysis of biomass via ReaxFF MD simulation: Free radicals driven synergistic deoxygenation and polymerization reactions

IF 5.8 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-04-14 DOI: 10.1016/j.jaap.2025.107131

Kaiyue Zheng , Zhijie Gong , Song Hu , Mengchuan Jia , Kai Xu , Jun Xu , Long Jiang , Yi Wang , Sheng Su , Jun Xiang

A deeper deoxygenation and upgrading of biomass could be realized through pressurized pyrolysis, whereas the product properties and reaction pathways from different biomass vary significantly, primarily due to components variations and interactions. This study employed reactive force field molecular dynamics (ReaxFF MD) to elucidate co-pyrolysis mechanisms of biomass three components at microcosmic level. The effects of temperatures and pressure on individual component pyrolysis were initially investigated. Results indicated that pressure significantly impacted the pyrolysis of cellulose and hemicellulose, particularly on cellulose, increasing its char yields at 1400–1800 K. The H₂O and CO₂ yields under pressure were markedly higher than atmospheric pressure. Moreover, by comparing calculated and simulated values, the influence of component interactions on product characteristics under atmospheric and pressurized conditions was analyzed. Simulation results showed that pressure enhanced component interactions, particularly between cellulose and lignin (C-L) at temperatures above 1700 K, with a maximum deviation of 13.97 % in char yields. The actual C₂H₂O₂ and C₃H₄O₃ yields were notably higher than calculated at 1800–2300 K, especially under pressure. C-L co-pressurized pyrolysis resulted in more -CO and -COOH groups removal as aldehyde and carboxylic acid small molecule volatiles. In contrast, cellulose-hemicellulose (C-H) interaction mainly occurred during volatiles secondary reaction at elevated temperature and pressure. These results are consistent with our existing experimental data. Ultimately, by tracking C, H, and O elements dynamic migration, a crucial “initiator” role of radicals in synergistic reactions was revealed. The work provides theoretical support for producing high-quality biochar via optimizing pressure conditions and components regulation.

{"title":"Investigation of components interaction during pressurized pyrolysis of biomass via ReaxFF MD simulation: Free radicals driven synergistic deoxygenation and polymerization reactions","authors":"Kaiyue Zheng , Zhijie Gong , Song Hu , Mengchuan Jia , Kai Xu , Jun Xu , Long Jiang , Yi Wang , Sheng Su , Jun Xiang","doi":"10.1016/j.jaap.2025.107131","DOIUrl":"10.1016/j.jaap.2025.107131","url":null,"abstract":"<div><div>A deeper deoxygenation and upgrading of biomass could be realized through pressurized pyrolysis, whereas the product properties and reaction pathways from different biomass vary significantly, primarily due to components variations and interactions. This study employed reactive force field molecular dynamics (ReaxFF MD) to elucidate co-pyrolysis mechanisms of biomass three components at microcosmic level. The effects of temperatures and pressure on individual component pyrolysis were initially investigated. Results indicated that pressure significantly impacted the pyrolysis of cellulose and hemicellulose, particularly on cellulose, increasing its char yields at 1400–1800 K. The H<sub>2</sub>O and CO<sub>2</sub> yields under pressure were markedly higher than atmospheric pressure. Moreover, by comparing calculated and simulated values, the influence of component interactions on product characteristics under atmospheric and pressurized conditions was analyzed. Simulation results showed that pressure enhanced component interactions, particularly between cellulose and lignin (C-L) at temperatures above 1700 K, with a maximum deviation of 13.97 % in char yields. The actual C<sub>2</sub>H<sub>2</sub>O<sub>2</sub> and C<sub>3</sub>H<sub>4</sub>O<sub>3</sub> yields were notably higher than calculated at 1800–2300 K, especially under pressure. C-L co-pressurized pyrolysis resulted in more -C<img>O and -COOH groups removal as aldehyde and carboxylic acid small molecule volatiles. In contrast, cellulose-hemicellulose (C-H) interaction mainly occurred during volatiles secondary reaction at elevated temperature and pressure. These results are consistent with our existing experimental data. Ultimately, by tracking C, H, and O elements dynamic migration, a crucial “initiator” role of radicals in synergistic reactions was revealed. The work provides theoretical support for producing high-quality biochar via optimizing pressure conditions and components regulation.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"190 ","pages":"Article 107131"},"PeriodicalIF":5.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143830219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0