{"title":"Valorization of plastic waste via hydrothermal liquefaction and hydrothermal gasification: Review and bibliometric analysis","authors":"Alshaimaa Moustafa , Kareem Abdelrahman , Amal Abdelhaleem , Irene Samy Fahim","doi":"10.1016/j.jaap.2025.107112","DOIUrl":"10.1016/j.jaap.2025.107112","url":null,"abstract":"<div><div>Plastic waste remains a pressing environmental issue, with conventional recycling methods falling short in efficiency. Hydrothermal liquefaction (HTL) and hydrothermal gasification (HTG) emerge as innovative approaches, transforming plastics like polyethylene (PE), polypropylene (PP), and mixed municipal waste into valuable outputs such as bio-crude oil and syngas. These processes operate under subcritical water conditions (300–350°C) or supercritical water conditions (400–450°C), offering versatile solutions for waste management. This review synthesizes findings from 250 Scopus-indexed articles spanning 1998–2024, tracing the evolution of research from single-polymer studies to investigations of complex, real-world waste streams. Despite progress, challenges remain, including gaps in understanding reaction kinetics and barriers to industrial scalability. Overcoming these hurdles is essential for embedding hydrothermal technologies within the circular economy, enabling efficient resource recovery and pollution reduction. This article delivers a detailed bibliometric analysis and literature review, underscoring the promise of hydrothermal methods for sustainable plastic waste management.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107112"},"PeriodicalIF":5.8,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783127","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}
Riyi Lin , Ruiqi Liu , Lijuan Wang , Yiya Wang , Ningmin Zhu , Dengyu Chen , Liqiang Zhang
{"title":"Effects of B-doping on the physicochemical structure and CO2 adsorption property of the walnut shell bio-char","authors":"Riyi Lin , Ruiqi Liu , Lijuan Wang , Yiya Wang , Ningmin Zhu , Dengyu Chen , Liqiang Zhang","doi":"10.1016/j.jaap.2025.107114","DOIUrl":"10.1016/j.jaap.2025.107114","url":null,"abstract":"<div><div>B-doping walnut shell char was prepared by the premodified doping method. The effects of B-doping amount, doping temperature, and coupling activation agent (activator amount, activation temperature) on the physicochemical structure and CO<sub>2</sub> adsorption performance of walnut shell biochar were investigated using BET, SEM, Raman, XRD, FT-IR, and XPS characterization techniques. The results indicated that B-doping walnut shell char exhibited a high specific surface area, and the pore structure was dominated by micropores. As the amount of B-doping increased, the CO<sub>2</sub> adsorption capacity of walnut shell char initially rose and then declined. The optimal doping mass ratio was 2:1, and the best pyrolysis temperature was 800 °C. The biochar pores became more abundant and disorderly after KOH activation. Excessive amounts of activators could damage the pore structure of activated char, thereby reducing the adsorption performance. The optimal mass ratio of the activator to walnut shell char was 1:1. As the activation temperature increased, the adsorption capacity of activated char for CO<sub>2</sub> initially improved and subsequently declined. The optimal activation temperature of walnut shell char was 700 °C. The optimal CO<sub>2</sub> adsorption performance was achieved by the CK1–1–700, which was 76.70 % higher compared to W800 without B-doping. Additionally, CK1–1–700 exhibited good cyclic performance. B-doping and activation treatment significantly enhanced the CO<sub>2</sub> adsorption capacity of walnut shell char. These research findings could serve as a reference for the high-value utilization of biomass.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107114"},"PeriodicalIF":5.8,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776506","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}
Veronica D’Eusanio , Alessandro Girolamo Rombolà , Irene Coralli , Daniele Fabbri , Lorenzo Tassi , Andrea Marchetti
{"title":"Thermal degradation pathways in multi-component epoxy composites","authors":"Veronica D’Eusanio , Alessandro Girolamo Rombolà , Irene Coralli , Daniele Fabbri , Lorenzo Tassi , Andrea Marchetti","doi":"10.1016/j.jaap.2025.107107","DOIUrl":"10.1016/j.jaap.2025.107107","url":null,"abstract":"<div><div>In this study, the thermal degradation behavior of epoxy composites formulates with a bisphenol A (BPA) and bisphenol F (BPF) resin blend, a reactive alkyl glycidyl ether diluent, and quartz filler, cured with a cycloaliphatic amine hardener was investigated. Thermogravimetric analysis (TGA) and pyrolysis-gas chromatography/mass spectrometry (py-GC-MS) were employed to explore the degradation pathways and identify the key pyrolyzates. The results revealed that BPA and BPF degrade through distinct but interrelated mechanisms, producing major pyrolyzates such as phenol, BPA, and xanthene. The reactive diluent significantly influenced the pyrolysis profile by introducing unique long-chain hydrocarbons, alcohols, and ethers because of its incomplete incorporation into the polymer matrix. Despite its inert nature, the quartz filler reduced the abundance of pyrolyzates and increased the residual mass, improving the thermal stability of the composite without altering the degradation pathways. This study highlights the complex interplay between resin chemistry, reactive diluents, and fillers in determining thermal behavior. These insights are essential for optimising epoxy composite formulations to enhance their thermal stability and durability for high-performance applications.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107107"},"PeriodicalIF":5.8,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Sustainable biochar from empty fruit bunches: Technological innovations and future perspectives","authors":"Fitria Yulistiani , Aqsha , Yazid Bindar","doi":"10.1016/j.jaap.2025.107111","DOIUrl":"10.1016/j.jaap.2025.107111","url":null,"abstract":"<div><div>Indonesia's expansive agricultural landscape generates significant biomass residues, particularly from palm oil production, such as Empty Fruit Bunches (EFB). With 28.65 million metric tons of EFB produced annually, this underutilized resource presents an opportunity for sustainable biochar production. Biochar, a stable byproduct of biomass pyrolysis, offers a durable solution to improving soil quality, enhancing crop productivity, and sequestering carbon in acidic drylands. This review explores pyrolysis technologies for EFB conversion, focusing on heating methods, production scales, and their efficiency. EFB's high lignin content (34.9 %) supports its potential for biochar production, yielding solid residues with beneficial agronomic and environmental properties. However, challenges such as variability in feedstock composition, scalability, and energy efficiency persist. Innovations like microwave-assisted pyrolysis and renewable energy integration for heating show promise in addressing these constraints. The study highlights that optimizing pyrolysis conditions, such as temperature and residence time, alongside exploring continuous production methods and advanced reactor designs, is crucial. Future research must evaluate biochar’s effects on soil health and nutrient cycling through extensive field trials and assess its economic and environmental sustainability. EFB-derived biochar holds the potential to revolutionize sustainable agricultural practices and waste management, contributing to environmental conservation.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107111"},"PeriodicalIF":5.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761134","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}
{"title":"Formation of chloride products in the MSW (municipal solid wastes) pyrolysis process by Py-GC/MS method with key model components","authors":"Yande Cai , Ze Wang , Jianjun Wang , Songgeng Li","doi":"10.1016/j.jaap.2025.107113","DOIUrl":"10.1016/j.jaap.2025.107113","url":null,"abstract":"<div><div>The formation of chloride products in the process for pyrolysis of municipal solid wastes (MSW) with key model components was investigated by Py-GC/MS method. HCl and CH<sub>3</sub>Cl are identified as the most abundant chloride products for the individual pyrolysis of polyvinyl chloride (PVC) or corn straw (CS) in the range of 200–600 °C. For the pyrolysis of CS, a higher temperature is more favorable for the generation of HCl than that of CH<sub>3</sub>Cl. In the PVC pyrolytic products, chlorobenzene (Ph-Cl), benzyl chloride (Ph-CH<sub>2</sub>Cl), and 1-(chloroethyl)benzene (Ph-CHClCH<sub>3</sub>) are also detected but in extremely low amounts. For the co-pyrolysis of PVC/CS, the formation of CH<sub>3</sub>Cl is significantly promoted. The synergistic effect in the PVC/CS co-pyrolysis process is mainly attributed to the reaction between the HCl derived from PVC and the decomposition products of lignin. The products of Ph-Cl and Ph-CH<sub>2</sub>Cl are mainly generated from the cyclization of Cl-containing chain species. CH<sub>3</sub>Cl and Ph-CHClCH<sub>3</sub> are mainly generated from secondary reactions between HCl and other pyrolytic products. No remarkable synergistic effect is observed on the formations of chlorides in the co-pyrolysis of PVC/PP (polypropylene), while the generation of Ph-CHClCH<sub>3</sub> is significantly enhanced in the co-pyrolysis of PVC/PS (polystyrene).</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107113"},"PeriodicalIF":5.8,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746663","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}
Lijin Xie , Yu Shao , Kai Chen , Dongming Qi , Jiawei Li
{"title":"Insight into pyrolysis degradation of polyester/cotton blended fabric with a system of two-component independent flame-retardation by Py-GC/MS analysis","authors":"Lijin Xie , Yu Shao , Kai Chen , Dongming Qi , Jiawei Li","doi":"10.1016/j.jaap.2025.107109","DOIUrl":"10.1016/j.jaap.2025.107109","url":null,"abstract":"<div><div>Pyrolysis degradation of polyester/cotton (Terylene/cotton T/C) blended fabric is complex because the interaction of individual components generates more flammable volatiles and burns more intensely. Having previously reported a two-component independent flame-retardant (TIF) system of flame-retarding T/C blended fabric to inhibit the “scaffolding effect”, in which the polyester component was copolymerized of phosphorus containing flame retardant monomers and the cotton component was finished by grating vinyl ammonium phosphate (AMVP) (Xie et al. <em>Polymer Degradation and Stability</em>, 2024, 220, 110638). However, how these treatments influence the interaction between the cotton and polyester components during pyrolysis, the mechanisms behind flame retardancy remains unclear. Here a thorough study of the pyrolysis degradation of cotton, polyester, and T/C blended fabric with or without treatment using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) to identify the detailed pyrolysis products, allowing depicting the interactions of two components and the flame-retardant (FR) mechanism. The pyrolysis results of the TIF system show that the composition of pyrolysis products had changed compared to the commercial single FR finishing blended fabrics. The present of high benzoic acid/acetaldehyde ratio (2.85) demonstrated that the TIF system was inhibiting pyrolysis interference between the polyester and cotton components, in which independently charring and flame retardant, forming char barrier layers. Additionally, a high P-containing compounds (1.61 %) provided an explanation for the lower flammability. This work will shed light on the forthcoming research of FR mechanism for the new component independent FR blended fabrics.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107109"},"PeriodicalIF":5.8,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761171","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}
Zhi Li , Kai Shen , Min Hu , Miao Liu , Fang Zhou , Ming Li , Qiong Liu , Xiaoxu Wu , Weiwang Chen
{"title":"Pyrolysis behavior, kinetics, and mechanism of polyimide aerogels","authors":"Zhi Li , Kai Shen , Min Hu , Miao Liu , Fang Zhou , Ming Li , Qiong Liu , Xiaoxu Wu , Weiwang Chen","doi":"10.1016/j.jaap.2025.107108","DOIUrl":"10.1016/j.jaap.2025.107108","url":null,"abstract":"<div><div>Polyimide aerogels (PIAs) have extensive application prospects in numerous fields for their appealing characteristics, including low density, superior thermal stability, high flexibility, and remarkable mechanical properties. However, the thermal safety of polyimide aerogels in practical applications has been neglected, the pyrolysis behaviors and reaction kinetics need to be clarified. In this work, PIAs with different repeat units from 10 to 60 were prepared using the sol-gel method, and the effect of repeat unit on the basic properties, microstructure, and thermal stability of polyimide aerogel was studied. The PIAs with a repeat unit of 40 have the lowest density, thermal conductivity, radial shrinkage, the highest porosity, the largest specific areas, and so on. Furthermore, the pyrolysis process and products of PIA were analyzed by TG-FTIR-MS. The pyrolysis kinetic parameters were calculated by model-free method and the predicted reaction model was chosen by CR and Malek method. The calculated kinetic parameters are in good agreement with the experimental data at different heating rates, which can guide the pyrolysis behavior and thermal safety of polyimide aerogels.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107108"},"PeriodicalIF":5.8,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143735010","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}
{"title":"Accelerated photodegradation of PMMA films: Synergistic effect of mixed solvents","authors":"Zhiping Xu , Xiangze Meng , Ying Liu, Rui Yang","doi":"10.1016/j.jaap.2025.107106","DOIUrl":"10.1016/j.jaap.2025.107106","url":null,"abstract":"<div><div>As a widely used and versatile polymer, poly (methyl methacrylate) (PMMA) is difficult to degrade in the natural environment due to the inertness of the C-C bonds in the polymer chain. Pyrolysis with a high temperature of about 450 °C is a major but not eco-friendly method of waste PMMA degradation today. Herein, we report a photodegradation process of PMMA accelerated by small amounts of tetrahydrofuran (THF) and chloroform (TCM) at near room temperature. Compared with the blank samples, the mixed solvents accelerated the production of the methyl methacrylate (MMA) by about 130 times. A synergistic effect between the components of the mixed solvent was proved by experiments and density functional theory (DFT) calculations. The reaction of TCM with THF promotes the chlorination of the ester group of PMMA, and finally causes the accelerated photo-depolymerization of PMMA in a condition with relative mild temperature required. This new mechanism has the potential to become a new strategy for upcycling PMMA waste plastics.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107106"},"PeriodicalIF":5.8,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143735029","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}
Xiaoyu Zhang , Shun Zhou , Jin Zhang , Jiuyi Liu , Xiaofeng Wang , Weijian Chen , Yanyan Li , Mengdie Cai , Lisheng Guo , Song Sun
{"title":"Effects of different heating methods on pyrolysis and smoke release characteristics of tobacco granules","authors":"Xiaoyu Zhang , Shun Zhou , Jin Zhang , Jiuyi Liu , Xiaofeng Wang , Weijian Chen , Yanyan Li , Mengdie Cai , Lisheng Guo , Song Sun","doi":"10.1016/j.jaap.2025.107099","DOIUrl":"10.1016/j.jaap.2025.107099","url":null,"abstract":"<div><div>Heated tobacco products (HTPs) have gradually become an important development direction of tobacco products because of their significant advantages in reducing the release of harmful components. To reveal the thermal degradation characteristics of the heated tobacco products is of great significance for the development of novel heated tobacco products. The effects of heating method on pyrolysis and smoke release of the tobacco granules were studied with in situ diffuse reflection Fourier transform infrared spectroscopy (DRIFTS) technology and infrared thermal imaging technology. The results showed that: 1)The different heating methods of tobacco granules had a great influence on the temperature field distribution. Among them, the bottom heating method had a more uniform temperature distribution and a higher average temperature than the central heating method. 2) Different heating methods directly led to the difference in the release of various chemical components. The DRIFTS spectra indicated that the release characteristic of gaseous products with different heating methods were different, while the release temperature ranges were slightly different due to the differences of chemical components. The bottom heating method was more conducive to smoke release. 3) The moisture content of tobacco granules also directly affected the pyrolysis process and the smoke release characteristics. Either too high or too low moisture content was not conducive to the pyrolysis process and smoke release. The mathematical model of the thermal degradation characteristics was established to predict the quality of tobacco granules and to provide theoretical guidance for the product development of heating tobacco.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107099"},"PeriodicalIF":5.8,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143735011","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}
Ji Liu , Hong-jin Zhang , Yuan-gu Xia , Bin Hu , Xin-hua Yuan , Zhen-xi Zhang , Xiao-yan Jiang , Li Zhao , Qiang Lu
{"title":"The fate of bromine during pyrolysis of tetrabromobisphenol A-bis(2,3-dibromopropyl ether): A combined experimental and computational study","authors":"Ji Liu , Hong-jin Zhang , Yuan-gu Xia , Bin Hu , Xin-hua Yuan , Zhen-xi Zhang , Xiao-yan Jiang , Li Zhao , Qiang Lu","doi":"10.1016/j.jaap.2025.107104","DOIUrl":"10.1016/j.jaap.2025.107104","url":null,"abstract":"<div><div>A thorough comprehension of the migration mechanism of Br is essential for the thermochemical recycling of waste electrical and electronic equipment (WEEE), given that brominated flame retardants (BFRs) are key components in WEEE. Tetrabromobisphenol A-bis(2,3-dibromopropyl ether) (TBBPA-DBPE) is a new BFR that has been widely used in WEEE in recent years, whereas the transformation of Br during the thermochemical recycling of TBBPA-DBPE has been rarely reported. In this study, the decomposition mechanism of TBBPA-DBPE pyrolysis to generate Br-containing products was investigated by combining experiments and density functional theory (DFT) calculations. The primary Br-containing products of TBBPA-DBPE pyrolysis were HBr, 1,2,3-tribromopropane, and bromophenols. During the initial stage of pyrolysis, TBBPA-DBPE predominantly undergoes the homolysis of the C–O and C–Br bonds, resulting in the formation of 1,2,3-tribromopropane. Subsequently, Br radicals and H atoms can react with TBBPA-DBPE and its intermediates to produce various Br-containing products, including HBr, 2,4,6-tribromophenol and 2,6-dibromophenol. Notably, the 2,6-dibromophenol radical serves as a critical precursor for the formation of brominated dioxins via C–O coupling reactions. This research provides a theoretical basis for managing Br during the thermochemical treatment of WEEE.</div></div>","PeriodicalId":345,"journal":{"name":"Journal of Analytical and Applied Pyrolysis","volume":"189 ","pages":"Article 107104"},"PeriodicalIF":5.8,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726137","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}