Journal of Analytical and Applied Pyrolysis最新文献_第10页

Synergistic enhancement of dechlorination and hydrochar performance via co-hydrothermal carbonization of textile dyeing sludge and garden waste 纺织印染污泥和园林废弃物共水热碳化协同提高脱氯和加氢性能

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-28 DOI: 10.1016/j.jaap.2025.107502

Zehua Zhao , Yue Qiao , Yi Wang , Yang Lv , Dapeng Zhang , Houhu Zhang , Yuanqing Bu , Chenyu Wang

Textile dyeing sludge (TDS) poses a challenge for both disposal and resource utilization. This study investigates the co-hydrothermal carbonization (co-HTC) of TDS and garden waste (GW) to promote the dechlorination of TDS and enhance the properties of derived hydrochar. TDS was mixed with GW in different ratios and reacted at 180°C to 260°C for 2–6 h. The dechlorination rate (DE) for TDS under standalone HTC was 7.79 %, whereas co-HTC with GW markedly increased the DE to 46.39 % – 66.78 %. Under appropriate HTC conditions and GW mix ratios, the DE increased by 11.9 % – 26.5 % compared with the theoretical value expected solely from the “dilution effect” of GW, indicating that synergistic dechlorination effect occurred between the components of GW and TDS, which further enhanced chlorine removal. Furthermore, considering typical downstream utilization scenarios of hydrochar, the influence of co-HTC on hydrochar performance was assessed in terms of fuel and adsorption properties. Co-HTC enhances the volatile matter and carbon content of the hydrochar, improving its fuel performance, the HHV increased from 10.42 MJ/kg to 18.14 MJ/kg, the volatile content increased from 54.55 % to a maximum of 75.80 %. Although the addition of GW partially obstructs the hydorchar’s porous structure, it also increases the amount of oxygen-containing functional groups, adsorption kinetics for two representative pollutants further demonstrated the altered adsorption behavior of co-HTC-derived hydrochar. Especially, the equilibrium adsorption amounts for MB increased from 32.80 mg/g to 45.99 – 52.97 mg/g. Overall, these findings provide new insights into the effective management of TDS through co-HTC with GW, highlighting its potential for resource recovery and environmental remediation.

纺织印染污泥的处理和资源化利用都面临着挑战。研究了TDS和园林垃圾（GW）的共水热碳化（co-HTC），以促进TDS的脱氯，提高衍生碳氢化合物的性能。将TDS与GW按不同比例混合，在180 ~ 260℃下反应2 ~ 6 h。单独HTC下TDS的脱氯率（DE）为7.79 %，而与GW联合HTC的脱氯率（DE）显著提高至46.39 % ~ 66.78 %。在适当的HTC条件和GW混合比例下，相对于仅通过GW的“稀释效应”得到的理论值，DE提高了11.9 % ~ 26.5 %，说明GW和TDS组分之间发生了协同脱氯作用，进一步增强了氯的去除率。此外，考虑到典型的碳氢化合物下游利用场景，从燃料性能和吸附性能两方面评估了co-HTC对碳氢化合物性能的影响。Co-HTC提高了烃类的挥发分和碳含量，提高了烃类的燃料性能，HHV从10.42 MJ/kg提高到18.14 MJ/kg，挥发分从54.55 %提高到75.80 %。虽然GW的加入部分阻碍了水合物的多孔结构，但也增加了含氧官能团的数量，对两种代表性污染物的吸附动力学进一步证明了co- htc衍生的水合物吸附行为的改变。特别是对MB的平衡吸附量从32.80 mg/g增加到45.99 ~ 52.97 mg/g。总的来说，这些发现为通过与GW的联合htc有效管理TDS提供了新的见解，突出了其在资源恢复和环境修复方面的潜力。

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引用次数: 0

Staged KHCO3 pyrolysis of Clausena lansium seeds: Correlating thermal parameters with hierarchical carbon electrodes for enhanced capacitive energy storage Clausena lan镧种子的阶段KHCO3热解：与分层碳电极的热参数相关以增强电容储能

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-28 DOI: 10.1016/j.jaap.2025.107498

Qing Xu , Shenwei Zhang , Xuanyuan Ni , Yunxing Zhao , Denian Li , Haoran Yuan

This study develops a staged pyrolysis protocol using KHCO₃ activation under inert nitrogen atmosphere to convert agricultural waste (Clausena lansium seeds) into hierarchical porous carbon. By precisely controlling thermal conditions—pre-carbonization at 400 °C followed by dual-stage activation (300°C hold, then 800 °C)—with optimized solid-to-activator ratios, we establish a correlation between pyrolysis parameters and material properties. The process leverages KHCO₃’s staged decomposition for controlled pore evolution, yielding carbon matrices with microporous dominance (specific surface area 1366 m² g⁻¹, microporosity 84 %) while preserving structural coherence. Chemical characterization confirms oxygen-functionalized surfaces and enhanced graphitization via XPS and Raman analyses. Electrochemical validation using KOH electrolyte demonstrates superior capacitive behavior (346.3 F g⁻¹ at 1 A g⁻¹, 242.5 F g⁻¹ at 20 A g⁻¹) and cycling stability (100.9 % retention after 10,000 cycles). Symmetric supercapacitors deliver 8.96 Wh kg⁻¹ energy density at 250 W kg⁻¹, confirming applicability in energy storage systems. Our pyrolysis methodology provides an eco-compatible route to transform biomass into functional carbon materials without aggressive etching agents.

本研究开发了一种惰性氮气氛下利用KHCO3活化将农业废弃物（Clausena lanum种子）转化为分级多孔碳的分阶段热解方案。通过精确控制热条件-在400 °C下预碳化，然后进行双阶段活化（300°C保持，然后800 °C） -优化固体与活化剂的比例，我们建立了热解参数与材料性能之间的相关性。该工艺利用KHCO3的阶段分解来控制孔隙演化，产生具有微孔优势的碳基质（比表面积1366 m2 g−1，微孔隙度84 %），同时保持结构一致性。化学表征通过XPS和拉曼分析证实了氧功能化表面和增强的石墨化。使用KOH电解质电化学验证演示了优越的电容行为(346.3 F g −1 1  g−1,242.5 F g−1在20  g−1)和循环稳定后(100.9 %保留10000周期)。对称超级电容在250 W kg−1时，能量密度为8.96 Wh kg−1，在储能系统中具有一定的适用性。我们的热解方法提供了一种生态相容的途径，将生物质转化为功能碳材料，而不需要腐蚀性蚀刻剂。

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引用次数: 0

From waste to watts: CoQDs on biochar as efficient catalysts for biomass-to-hydrogen conversion 从废物到瓦特：生物炭上的CoQDs作为生物质转化为氢的有效催化剂

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-27 DOI: 10.1016/j.jaap.2025.107495

Saimatun Nisa, Gaurav A. Bhaduri

This study presents the design and application of cobalt quantum dots (CoQDs) supported on walnut shell-derived biochar as efficient catalysts for microwave-assisted biomass pyrolysis. Two catalyst formulations (Co-0.1 M and Co-0.5 M), with average CoQD sizes of 2.45 nm and 3.90 nm, respectively, were synthesized via an energy-efficient in situ microwave-assisted method. Comprehensive characterization (FTIR, Raman, XPS, XRD, SAED, SEM-EDX, and TEM) confirmed successful CoQD dispersion on the carbonaceous matrix. Thermogravimetric analysis coupled with iso-conversional models (FWO, KAS, ST) revealed a substantial reduction in activation energy—from 229.16 kJ/mol (non-catalytic) to 200.64 kJ/mol and 146.42 kJ/mol for Co-0.1 M and Co-0.5 M, respectively. Kinetic compensation effects and mechanistic analyses using the Achar and Criado master plots indicated mixed nucleation and diffusion-controlled degradation. Catalytic pyrolysis at 600 °C significantly enhanced pyro-gas yield (from 52 % to 75 %) and increased hydrogen content in the gas phase (from 5 % to 25 %). GC-MS and GC analyses revealed enhanced formation of phenolic compounds and gasoline-range hydrocarbons in the bio-oil. These results underscore the potential of CoQDs-functionalized biochar as a cost-effective catalyst for selective, energy-efficient biomass valorization via microwave pyrolysis.

本研究介绍了核桃壳生物炭负载钴量子点（CoQDs）作为微波辅助生物质热解的高效催化剂的设计和应用。采用高效能的原位微波辅助方法合成了Co-0.1 M和Co-0.5 M两种催化剂，其CoQD平均尺寸分别为2.45 nm和3.90 nm。综合表征（FTIR, Raman， XPS， XRD， SAED， SEM-EDX和TEM）证实了CoQD在碳质基质上的成功分散。热重分析结合等转换模型（FWO， KAS， ST）显示Co-0.1 M和Co-0.5 M的活化能分别从229.16 kJ/mol（非催化）大幅降低到200.64 kJ/mol和146.42 kJ/mol。Achar和Criado主图的动力学补偿效应和机理分析表明，混合成核和扩散控制降解。600℃催化热解显著提高了热解气产率（从52 %提高到75 %）和气相氢含量（从5 %提高到25 %）。GC- ms和GC分析显示，生物油中酚类化合物和汽油级碳氢化合物的形成增强。这些结果强调了coqds功能化生物炭作为一种具有成本效益的催化剂的潜力，可以通过微波热解实现生物质的选择性、高能效增值。

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引用次数: 0

Phase separation with corresponding compositional changes in bio-oil from co-pyrolysis of extractive-rich waste biomass 从富含萃取物的废生物质共热解中分离出相应组分变化的生物油

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-27 DOI: 10.1016/j.jaap.2025.107491

Mukul Agrawal , Sanjeev Yadav , Pravakar Mohanty

The present work investigated the phenomenon of phase separation in bio-oil obtained by the co-pyrolysis of cotton stalk (CS) and cooked food waste (CFW). The experiments were conducted at three different carrier gas (N₂) flow rates (5, 7.5, and 10 LPM) and for their different mixing ratios in mixed feed to fast pyrolysis. At a low flow rate of 5LPM, the low mixing ratios of CFW in mixed feed (10 %, 25 %, and 50 %) produced the single-phase bio-oil and higher mixing ratios (>50 %) produced the two-phase bio-oil. However, at the higher flow rates (7.5 and 10 LPM), even a mixing ratio of 50 % CFW in mixed feed with CS produced a two-phase bio-oil. The two-phase bio-oil contained a water-rich phase, named as an aqueous phase (AP), and an oil phase (OP). A single-phase bio-oil mainly contained oxygenated organic compounds (OAC), furans, carbonyl compounds, and fatty acid alkyl esters (FAAEs) in varying proportions. However, in two-phase bio-oil, the AP contained the first three compounds in a large fraction, but additionally, it contained nitrogenated compounds, originating from the protein present in CFW. However, the oil phase was excessively enriched with the FAAEs (up to 88 %) formed by the thermal decomposition of lipids present in CFW and CS, along with minor compounds like non-alkyl esters, alcohols, and other carbonyl compounds. Finally, a reaction mechanism was proposed for dual-phase formation as well as for compositional changes in bio-oil in each phase.

研究了棉秆（CS）与熟食垃圾（CFW）共热解所得生物油的相分离现象。实验采用3种不同载气（N2）流量（5、7.5和10 LPM），以及不同载气（N2）在混合料中的混合比例进行快速热解。在5LPM的低流速下，混合饲料中CFW的混合比例较低（10 %、25 %和50 %）产生单相生物油，较高的混合比例（50 %）产生两相生物油。然而，在更高的流量（7.5和10 LPM）下，即使混合比为50% % CFW的混合饲料与CS也会产生两相生物油。两相生物油包含富水相，称为水相（AP）和油相（OP）。单相生物油主要含有不同比例的含氧有机化合物（OAC）、呋喃、羰基化合物和脂肪酸烷基酯（faae）。然而，在两相生物油中，AP含有前三种化合物的比例很大，但另外，它含有氮化物，来自CFW中存在的蛋白质。然而，油相过度富集了faae（高达88 %），这些faae是由CFW和CS中存在的脂类热分解形成的，同时还含有少量化合物，如非烷基酯、醇和其他羰基化合物。最后，提出了生物油双相形成及各相组分变化的反应机理。

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引用次数: 0

A bio-based flame retardant from a solvent-free approach endows epoxy resin with satisfactory flame retardancy, smoke suppression and mechanical strength 一种无溶剂的生物基阻燃剂使环氧树脂具有令人满意的阻燃性、抑烟性和机械强度

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-27 DOI: 10.1016/j.jaap.2025.107500

Zhixiong Huang, Yuzhan Lu, Wanglin Ying, Yi Liang, Zongyi Deng

Epoxy resin (EP) is widely used but highly flammable, limiting its applications requiring high flame retardancy. Traditional flame retardants typically rely on non-renewable petrochemicals and organic solvents. Herein, a novel phosphorus-nitrogen synergistic flame retardant (DFFA) was synthesized through a mild and solvent-free approach using 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), furfural (FF) and furfurylamine (FA) as raw materials. The resulting DFFA was incorporated into EP, endowing the composite with satisfactory flame retardancy, smoke suppression and mechanical strength. The limiting oxygen index (LOI) of the DDM cured EP with 1.5 wt% phosphorus content (DFFA-1.5) reached 30.6 %, and its UL94 rating reached V0 level. The incorporation of DFFA led to a significant reduction in fire hazard parameters. Specifically, the total heat release (THR), peak heat release rate (PHRR), average heat release rate (AHRR), and maximum smoke density were reduced to 70.0 MJ/m², 566.8 kW/m², 233.0 kW/m², and 716.8, respectively, representing remarkable reductions of 18.1 %, 56.2 %, 18.0 %, and 15.9 % compared to those of pristine EP. Possible flame retardant mechanisms were revealed. DFFA not only altered pyrolysis path of EP, but also released numerous phosphorus-containing radicals that could capture and terminate highly reactive radicals. Moreover, DFFA promoted formation of a relatively compact expanded char layer that exerted physical barrier effect. The flexural and tensile strengths of the 4,4’-diaminodiphenylmethane (DDM) cured EP with 0.75 wt% phosphorus content (DFFA-0.75) reached 140.3 MPa and 71.7 MPa, respectively, which are 12.6 % and 50.9 % higher than those of the pristine EP. This enhancement is attributed to the crack deflection mechanism induced by DFFA.

环氧树脂（EP）用途广泛，但具有高度可燃性，限制了其对阻燃性要求较高的应用。传统的阻燃剂通常依赖于不可再生的石化产品和有机溶剂。以9,10-二氢-9-氧-10-磷菲-10-氧化物（DOPO）、糠醛（FF）和糠胺（FA）为原料，采用温和无溶剂的方法合成了一种新型磷氮协同阻燃剂（DFFA）。将所得的DFFA掺入EP中，使复合材料具有满意的阻燃性、抑烟性和机械强度。磷含量为1.5 wt% （DFFA-1.5）的DDM固化EP的极限氧指数（LOI）达到30.6 %，UL94等级达到V0级。DFFA的加入导致火灾危险参数的显著减少。其中，总放热率（THR）、峰值放热率（PHRR）、平均放热率（AHRR）和最大烟密度分别降至70.0 MJ/m2、566.8 kW/m2、233.0 kW/m2和716.8 kW/m2，与原始EP相比分别显著降低18.1 %、56.2 %、18.0 %和15.9 %。揭示了可能的阻燃机理。DFFA不仅改变了EP的热解路径，还释放了大量的含磷自由基，这些含磷自由基可以捕获和终止高活性自由基。此外，DFFA促进了相对致密的膨胀炭层的形成，发挥了物理屏障效应。磷含量为0.75 wt% （DFFA-0.75）的4,4′-二氨基二苯甲烷（DDM）固化EP的弯曲强度和拉伸强度分别达到140.3 MPa和71.7 MPa，比原始EP分别提高12.6 %和50.9 %。这种增强归因于DFFA引起的裂纹挠曲机制。

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引用次数: 0

Study on the mechanism of Pb and Cd removal by vacuum high-temperature calcination of medicinal hearth glycite 药炉甘草酸真空高温煅烧脱除铅、镉机理研究

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-27 DOI: 10.1016/j.jaap.2025.107497

Guangyu Li , Yanling Pan

This study addresses critical quality issues in commercially available calamine, specifically its high iron content, insufficient active components, and excessive levels of toxic heavy metals lead (Pb) and cadmium (Cd). Through systematic analysis and process optimization, we comparatively evaluated traditional calcination against an innovative vacuum calcination method for calamine purification. The results demonstrate that zinc, cadmium, and lead predominantly exist as ZnCO₃, CdS, and PbCO₃, respectively. While ZnCO₃ decomposes into ZnO and CO₂ at 1000°C under both atmospheric and vacuum (10 ³ Pa) conditions, the vacuum environment promotes more complete decomposition. More importantly, CdS and PbCO₃ exhibit fundamentally distinct decomposition pathways under different atmospheres. In air, CdS oxidizes to solid CdO and gaseous SO₂, while PbCO₃ converts to solid PbO and CO₂, resulting in ineffective heavy metal removal. In contrast, vacuum calcination enables complete volatilization through different mechanisms: CdS dissociates into gaseous Cd and S₂, while PbCO₃ decomposes into volatile PbO and CO₂, allowing all gaseous products to escape the system effectively. Under optimal conditions (1000°C, 10 ³ Pa, 30 min), we achieved remarkable removal efficiencies of 99.82 % for Cd and 99.90 % for Pb, producing calamine that meets stringent pharmaceutical-grade standards. This work provides both theoretical insights and practical solutions for producing high-purity mineral-based pharmaceuticals.

本研究解决了市售炉甘石的关键质量问题，特别是其高铁含量，活性成分不足，以及有毒重金属铅（Pb）和镉（Cd）水平过高。通过系统分析和工艺优化，对传统煅烧法和真空煅烧法净化炉甘石进行了对比评价。结果表明，锌、镉和铅主要以ZnCO₃、CdS和PbCO₃的形式存在。而ZnCO₃在1000℃的大气和真空（10 ³Pa）条件下都分解成ZnO和CO₂，真空环境促进更完全的分解。更重要的是，cd和PbCO₃在不同的大气下表现出根本不同的分解途径。在空气中，CdS氧化为固体CdO和气态SO₂，而PbCO₃转化为固体PbO和CO₂，导致重金属去除效果不显著。相比之下，真空煅烧可以通过不同的机制实现完全的挥发：CdS分解成气态Cd和S₂，而PbCO₃分解成挥发性PbO和CO₂，允许所有的气态产物有效地从系统中逸出。在最佳条件（1000°C, 10 ³Pa, 30 min）下，我们对Cd和Pb的去除率分别达到99.82 %和99.90 %，生产的炉甘石符合严格的制药级标准。这项工作为生产高纯度矿物基药物提供了理论见解和实际解决方案。

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引用次数: 0

Mesophase pitch formation and needle coke production from catalytic/ thermal pyrolysis oil blends through staged carbonization 催化/热裂解油混馏分阶段碳化形成中间相沥青和针状焦

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-26 DOI: 10.1016/j.jaap.2025.107493

Xiaohan Jin , Junyu Wang , Yaru Li , Zheng Zhang , Wenbo Qu , Ying Yang , Nannan Chen , Liming Dong , He Liu , Aijun Guo

The co-carbonization behavior of catalytic pyrolysis slurry oil (PO) and thermal pyrolysis ethylene tar (ET) was systematically investigated to optimize needle coke feedstock formulation and enhance product performance. The influence of blending ratio on coke induction period, hydrogen-donating ability (HDA), mesophase development, and final needle coke properties were evaluated using thermal treatment, spectroscopic analyses, and morphological characterization. Results indicated that in the first-stage co-carbonization, increasing ET content shortened the coke induction period and reduced HDA, leading to accelerated viscosity buildup, premature mesophase solidification, and suppressed domain coalescence. Although higher ET proportions increased mesophase content, excessive ET (>50 wt%) caused severe over-carbonization, pore formation, and deterioration of optical texture. In the second-stage co-carbonization, fiber texture development in semi-coke was improved when ET content was ≤ 50 wt%, and even higher ET content induced evident mosaic structures with poor anisotropy. In the third-stage co-carbonization, calcination enhanced crystalline ordering in all samples; however, needle coke from high ET blends exhibited lower true density, higher coefficient of thermal expansion (CTE), and abundant structural defects. Optimal performance was achieved with a 50 wt% ET blend, yielding needle coke with CTE (2.51 ×10⁻⁶ ℃⁻¹) and true density (2.184 g cm⁻³) meeting industrial specifications for ultra-high-power graphite electrodes. As a lithium-ion battery anode, NC-50 delivered a high reversible capacity (323.8 mAh g⁻¹ after 600 cycles) and excellent rate capability. These results demonstrate that judicious PO/ET blending effectively balances carbonization reactivity, mesophase growth, and final coke properties, enabling the production of high-quality needle coke for both electrode and energy storage applications.

系统研究了催化热解浆油（PO）与热热解乙烯焦油（ET）的共碳化行为，以优化针状焦原料配方，提高产品性能。通过热处理、光谱分析和形貌表征，评价了掺合比例对焦炭诱导期、给氢能力、中间相发展和最终针状焦性能的影响。结果表明，在第一阶段共碳化过程中，增加ET含量缩短了焦炭诱导期，降低了HDA，加速了黏度的积累，加速了中间相的凝固，抑制了区域的聚结。虽然较高的ET比例增加了中间相含量，但过多的ET （>50 wt%）会导致严重的过碳化、孔隙形成和光学织构的恶化。在第二阶段共碳化中，当ET含量≤ 50 wt%时，半焦纤维的织构发育得到改善，更高的ET含量诱导出明显的马赛克结构，各向异性较差。在第三阶段共碳化中，煅烧增强了所有样品的晶体有序性；而高ET共混的针状焦表现出较低的真密度、较高的热膨胀系数（CTE）和丰富的结构缺陷。当掺量为50% wt% ET时，得到的针状焦炭性能最佳，CTE（2.51 ×10−6℃−1）和真密度（2.184 g cm−3）满足超高功率石墨电极的工业要求。作为锂离子电池的阳极，NC-50具有很高的可逆容量（循环600次后为323.8 mAh g - 1）和出色的倍率能力。这些结果表明，明智的PO/ET混合有效地平衡了碳化反应性、中间相生长和最终焦的性质，从而能够生产出用于电极和储能应用的高质量针状焦。

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引用次数: 0

Migration and evolution of N-containing species during pyrolysis of distillers' grains 酒糟热解过程中含氮物质的迁移与演化

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-26 DOI: 10.1016/j.jaap.2025.107489

Tongxiao Zhou , Han Zhang , Fei Gong , Jingchao Wei , Hongying Liu , Bangda Wang , Xia Jiang

Understanding nitrogen chemistry during fast pyrolysis of protein-rich lignocellulosic biomass is essential for producing low-nitrogen bio-oil, while the nitrogen migration and transformation pathways among three-phase products remain inadequately elucidated. This study investigated nitrogen transformation mechanisms during distillers' grains (DGs) pyrolysis by characterizing nitrogenous products across 400–800 °C. Results indicated that protein-N constituted > 75 % of nitrogen in DGs. During pyrolysis, protein-N underwent cyclization and dimerization to form pyrrolic-N, pyridinic-N, and quaternary-N in biochar. Pyrrolic-N and pyridinic-N contents decreased at 700–800 °C due to partial conversion to quaternary-N, which increased continuously. Nitrogen-containing compounds in DGs-derived bio-oil comprised primarily amines/amides and N-heterocycles. Amines/amides originated mainly from protein decarboxylation, whereas N-heterocycles derived predominantly from pyridinic-N, pyrrolic-N, and quaternary-N decomposition. Increasing temperature intensified protein decarboxylation and decomposition of pyridinic-N/pyrrolic-N, elevating amines/amides and N-heterocycles in bio-oil. At 400–700 °C, amines/amides underwent cracking and cyclization to form additional N-heterocycles, increasing their content. At 800 °C, thermal instability triggered ring-opening reactions in N-heterocycles, regenerating amines/amides. Furthermore, NH₃ and HCN yields rose with temperatures: NH₃ was primarily from protein deamination and amine/amide decomposition, and HCN was from pyridinic-N/pyrrolic-N ring-opening and nitrile cracking. Based on nitrogen speciation evolution, this study presented the first systematic outline of the comprehensive transformation pathway governing the fate of nitrogen among its various products during DG pyrolysis. This work provides a theoretical foundation for producing high-quality bio-oil from nitrogen-rich biomass via fast pyrolysis.

了解富含蛋白质的木质纤维素生物质快速热解过程中的氮化学对生产低氮生物油至关重要，而三相产物中氮的迁移和转化途径仍不充分阐明。本研究通过表征400-800°C的含氮产物，探讨了酒糟热解过程中的氮转化机制。结果表明，蛋白质n占DGs中氮含量的>； 75 %。在热解过程中，蛋白质- n在生物炭中发生环化和二聚形成吡咯- n、吡啶- n和季铵盐- n。在700 ~ 800℃时，吡咯- n和吡啶- n含量因部分转化为季铵盐而下降，并持续增加。dgs衍生生物油中的含氮化合物主要由胺/酰胺和n-杂环组成。胺/酰胺主要来源于蛋白质脱羧，而n -杂环主要来源于吡啶- n、吡咯- n和季铵盐- n分解。温度升高促进了生物油中蛋白质的脱羧和吡啶- n /吡啶- n的分解，提高了生物油中胺/酰胺和n -杂环的含量。在400-700℃时，胺/酰胺发生裂解和环化，形成额外的n -杂环，增加了它们的含量。在800℃时，热不稳定性引发n -杂环开环反应，再生胺/酰胺。NH3和HCN产率随温度升高而升高，NH3主要来自蛋白质脱胺和胺/酰胺分解，HCN主要来自吡啶- n /吡啶- n开环和腈裂解。基于氮的形态演化，本研究首次系统概述了DG热解过程中氮在不同产物间的综合转化途径。该研究为富氮生物质快速热解制备高品质生物油提供了理论基础。

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引用次数: 0

Nonlinear evolutionary characteristics and early warning methods of coal spontaneous combustion: Implications for coal mine disaster warning 煤炭自燃的非线性演化特征及预警方法：对煤矿灾害预警的启示

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-25 DOI: 10.1016/j.jaap.2025.107492

Teng Ma , Binbin Ma , Xiaowei Zhai , Bobo Song , Ya-E. Bai , Ling Liu , Haoyu Yang , Weigang Wang , Binbin He , Xiaokun Chen

To reveal the dynamic evolution of coal spontaneous combustion (CSC) and develop an efficient warning method, this study analyzes gas release behavior and the evolution of functional groups during CSC utilizing the self-built program controlled temperature rising apparatus and Fourier transform infrared spectroscopy (FTIR). The results indicate that during the slow-oxidation and critical-temperature stages, oxygen consumption and the release of carbon oxygen gases proceed slowly; during the rapid-oxidation stage, hydrocarbon gases begin to form; whereas in the combustion stage, carbon oxygen gas and hydrocarbon gas are released intensely. Based on the nonlinear characteristics of CSC and the results of Pearson correlation analysis, an early warning method is proposed that adopts CO, C₂H₄, and Graham coefficient as the main indicators, whereas CO₂, O₂, O₂/(CO+CO₂), CO/CO₂, and C₂H₆ serve as auxiliary indicators. By combining the advantages of particle swarm optimization (PSO) and genetic algorithm (GA), a PSO-GA-BPNN prediction model was developed. The model was trained on 112 samples collected from four Jurassic coal seams in northern Shaanxi, with 80 % used for training and 20 % for testing, achieving an RMSE of 5.6429 and an R² of 0.9944, significantly outperforming the other five models. Shapley Additive Explanations (SHAP) analysis was used to quantitatively evaluate the contributions of main and auxiliary indicators to the model predictions, verifying the dominant role of the main indicators in the prediction process. The results provide guidance for safe production and sustainable development of the coal industry, contributing to the achievement of carbon peaking and carbon neutrality goals.

为了揭示煤自燃过程的动态演化规律，建立有效的预警方法，利用自建程控温升仪和傅里叶变换红外光谱（FTIR）对煤自燃过程中的气体释放行为和官能团演化进行了分析。结果表明：在缓慢氧化和临界温度阶段，氧气消耗和碳氧气体释放缓慢；在快速氧化阶段，烃类气体开始形成；而在燃烧阶段，碳氧气体和碳氢气体释放强烈。基于CSC的非线性特点和Pearson相关分析结果，提出了以CO、C2H4和Graham系数为主要指标，CO2、O2、O2/(CO+CO2)、CO/CO2和C2H6为辅助指标的预警方法。结合粒子群算法（PSO）和遗传算法（GA）的优点，建立了PSO-GA- bpnn预测模型。该模型以陕北4个侏罗系煤层采集的112个样本为样本进行训练，以80% %用于训练，20% %用于测试，RMSE为5.6429，R2为0.9944，显著优于其他5个模型。采用Shapley加性解释（SHAP）分析定量评价了主辅助指标对模型预测的贡献，验证了主指标在预测过程中的主导作用。研究结果对煤炭工业的安全生产和可持续发展具有指导意义，有助于实现碳调峰和碳中和目标。

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引用次数: 0

An effective strategy for clean production of coal-based humic acids by step-wise oxidation 逐步氧化煤基腐植酸清洁生产的有效策略

IF 6.2 2区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Analytical and Applied Pyrolysis

Pub Date : 2025-11-25 DOI: 10.1016/j.jaap.2025.107494

Chuang Zhang , Chen Xu Chen , Wei Jiang , Wen Li , Jing-Pei Cao , Xiao-Yan Zhao

Lignite is a promising raw material to afford high-quality humic acids due to the high oxygen contents. A step-wise oxidation approach combining hydrogen peroxide (H₂O₂) pretreatment and ozone oxidation was used to effectively oxidize depolymerized Shengli lignite (SL) for coal-based humic acids production. The organic matter of pretreated SL (PTSL) was oxidized to humic acids by ozone at room temperature, with the highest conversion and humic acids yield of 87.42 % and 80.14 %, respectively. After two cycles, the total conversion of PTSL reached 91.08 % and the total humic acids yield reached 91.26 %. The synergistic effect of the step-wise oxidation leads to the complete degradation of the macromolecular network in coal. H₂O₂ oxidation initially depolymerizes the macromolecular network of coal by cleaving the weaker bridge bonds and alkyl side chains. Oxygen radicals generated by ozone attack the stronger covalent bonds in the coal, leading to deep decomposition of the coal into humic acids. This work provides a valuable strategy for exploring the structural characteristics of coal and efficient conversion of coal under mild conditions.

褐煤含氧量高，是生产高质量腐植酸的理想原料。采用双氧水预处理和臭氧氧化相结合的分步氧化方法，对解聚胜利褐煤进行了有效氧化，用于煤基腐植酸生产。预处理后的SL （PTSL）有机质在室温下被臭氧氧化为腐植酸，转化率最高，腐植酸收率最高，分别为87.42 %和80.14 %。经过两次循环后，PTSL总转化率达到91.08 %，腐植酸总收率达到91.26 %。阶梯式氧化的协同作用导致煤中大分子网络的完全降解。H2O2氧化首先通过破坏较弱的桥键和烷基侧链来解聚煤的大分子网络。臭氧产生的氧自由基攻击煤中较强的共价键，导致煤的深度分解成腐植酸。这项工作为探索煤的结构特征和温和条件下煤的高效转化提供了有价值的策略。

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引用次数: 0