Thermochimica Acta最新文献_第6页

Kinetics of water dissolution in liquid carbon dioxide and its role in coal dewatering 水在液态二氧化碳中的溶解动力学及其在煤脱水中的作用

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-21 DOI: 10.1016/j.tca.2025.180170

Seungtaek Lee , Hakduck Kim , Donghyeok Park , Heechang Lim , Juhun Song

Coal dewatering using liquid carbon dioxide (LCO₂) or supercritical CO₂ (ScCO₂) has been regarded as more effective than conventional thermal drying methods. This is because coal properties such as pore structure, surface area, and surface chemical groups are not significantly altered at relatively low temperatures associated with LCO₂ treatment. In this application, understanding the precise mechanism by which LCO₂ interacts with water confined within coal pores is essential. However, direct evidence demonstrating the relationship between the water-dissolution kinetics and coal dewatering has been lacking.

In this study, the extent of water removal from coal was measured under LCO₂ and ScCO₂. A shadowgraph technique was employed to observe the time-dependent behavior of water dissolution in LCO₂ under coal-free condition. The water removal from coal showed an exponential increase with increasing CO₂ saturation pressures, reaching a maximum of approximately 40 %-equivalent to 0.4 g of water removed per 1 g of coal-under ScCO₂. The similar time-dependent trend in water removal was also observed for single water droplet under coal-free condition. This similarity was observed because the water confined within coal pores was exposed to LCO₂ and subsequently dissolved into it. This finding indicates that water dissolution into LCO₂ predominantly governs the desorption of water molecules from coal.

利用液态二氧化碳（LCO2）或超临界二氧化碳（ScCO2）进行煤脱水被认为比传统的热干燥方法更有效。这是因为在与LCO2处理相关的相对低温下，煤的孔隙结构、表面积和表面化学基团等性质没有显著改变。在这种应用中，了解LCO₂与煤孔隙中的水相互作用的精确机制至关重要。然而，水溶解动力学与煤脱水之间关系的直接证据一直缺乏。在本研究中，测定了LCO₂和ScCO₂作用下煤的脱水程度。采用阴影法研究了无煤条件下LCO₂中水溶解的随时间变化规律。随着CO 2饱和压力的增加，煤的除水率呈指数增长，达到最大值约40%，相当于每1 g煤在CO 2作用下除水0.4 g。在无煤条件下，单水滴的脱水也有类似的随时间变化的趋势。观察到这种相似性是因为煤孔隙中的水暴露在LCO2中，随后溶解在LCO2中。这一发现表明，水溶解成LCO2主要控制煤中水分子的解吸。

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引用次数: 0

A novel near-infrared fluoro-photoacoustic probe for NIR/PA dual-model imaging and photothermal therapy in breast cancer 一种新型近红外荧光光声探针，用于近红外/PA双模型成像和乳腺癌光热治疗

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-21 DOI: 10.1016/j.tca.2025.180168

Pin Wang , Jie Wang , Neng-weng Chen , Li-heng Lu , Jie Xing , Bo Yuan , Ai-guo Wu , Juan Li

Introducing multiple iodine atoms into a heptamethine cyanine scaffold harnesses the heavy-atom effect to promote non-radiative decay, thereby achieving a remarkably high photothermal conversion efficiency (η = 61.0%) while retaining intense fluorescence in the near-infrared II (NIR-II) window. This structural optimization enables efficient light-to-heat conversion and enhanced photoacoustic contrast, making the system suitable for dual-modality imaging. Upon encapsulation into biocompatible nanomicelles, the resulting probes form stable, tumor-targeting colloids that exhibit concentration-dependent photothermal heating and superior photoacoustic responses compared with conventional cyanine analogues. In vivo studies confirm efficient tumor accumulation, low systemic toxicity, and optimal photothermal ablation. Collectively, these findings highlight heavy-atom-engineered heptamethine cyanines as a quantitatively optimized and mechanistically innovative platform for NIR-II fluorescence/photoacoustic dual imaging and image-guided photothermal cancer therapy.

将多个碘原子引入到七甲基菁支架中，利用重原子效应促进非辐射衰变，从而实现了非常高的光热转换效率（η = 61.0%），同时在近红外II （NIR-II）窗口中保持了强烈的荧光。这种结构优化实现了高效的光热转换和光声对比度增强，使系统适合双模成像。在被封装到生物相容性纳米胶束中后，所得到的探针形成稳定的肿瘤靶向胶体，与传统的花青素类似物相比，它们表现出浓度依赖的光热加热和优越的光声响应。体内研究证实了有效的肿瘤积累，低全身毒性和最佳光热消融。总之，这些发现突出了重原子工程七甲基菁氨酸作为定量优化和机械创新的平台，用于NIR-II荧光/光声双成像和图像引导光热癌症治疗。

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引用次数: 0

Transpiration cooling with phase change under extreme thermal environment: comparative analysis between numerical coupling simulations and high-temperature gas flow wind tunnel experiments 极端热环境下相变蒸腾冷却：数值耦合模拟与高温气流风洞实验对比分析

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-15 DOI: 10.1016/j.tca.2025.180157

Xiangchun Sun , Yifei Liu , Ling Zhao , Jin Zhao , Guice Yao , Dongsheng Wen

Transpiration cooling has become one of the most promising thermal protection approaches to overcome the extreme aerodynamic heat load for hypersonic flight. However, numerical coupling simulation method between the freestream gas flow and the porous flow considering phase change during transpiration cooling process using liquid coolant is still limited to accurately predict the cooling performance, especially further validating it by experimental method. In this work, a multi-region numerical coupling simulation strategy is firstly developed to investigate the phase-change transpiration cooling. To validate the numerical simulation method, an experimental platform using combustion gas flow is established to perform the transpiration cooling test using liquid coolant under the free-flow with Mach 1.36 and static temperature of 2800 K. Two typical porous structures are employed to investigate the transpiration cooling performance, and comparative analysis between the numerical simulation results and the combustion-gas flow experimental results are conducted. The results show that, the accuracy of the proposed coupled numerical method can be verified with the maximum deviation of stagnation temperature prediction less than 6%. The effect of nosecone curvature on cooling effectiveness is further revealed by numerical method, indicating that increasing curvature can enhance both stagnation-region cooling performance and coolant film coverage efficiency downstream. This work provides a quantitatively comparative analysis of the transpiration results between numerical simulations and combustion-gas flow experiments, offering a valuable reference for the future design of transpiration cooling system with phase change.

蒸腾冷却已成为克服高超声速飞行极端气动热负荷的最有前途的热防护方法之一。然而，液冷剂蒸腾冷却过程中考虑相变的自由流气流与多孔气流之间的数值耦合模拟方法仍然局限于对冷却性能的准确预测，特别是通过实验方法进一步验证。本文首次提出了一种多区域数值耦合模拟策略来研究相变蒸腾冷却。为了验证数值模拟方法，建立了燃烧气流实验平台，在马赫数为1.36、静态温度为2800 K的自由流动条件下，采用液冷剂进行了蒸腾冷却试验。采用两种典型多孔结构对其蒸腾冷却性能进行了研究，并将数值模拟结果与燃烧-气体流动实验结果进行了对比分析。结果表明，所提出的耦合数值方法的精度可以得到验证，滞止温度预测的最大偏差小于6%。通过数值计算进一步揭示了鼻锥曲率对冷却效率的影响，表明增大鼻锥曲率既能提高停滞区冷却性能，又能提高下游冷却液膜覆盖效率。本文对数值模拟与燃烧-气体流动实验的蒸腾结果进行了定量对比分析，为今后设计相变蒸腾冷却系统提供了有价值的参考。

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引用次数: 0

A machine learning based calibration method for differential scanning calorimetry 基于机器学习的差示扫描量热标定方法

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-15 DOI: 10.1016/j.tca.2025.180158

Aohua Xiao , Zhengyang Zhang , Zhongxin Qian , Ao Xiao , Dongfang Hu , Jinxin Xu , Xudong Lu , Mohammad Mahdi Heyhat , Jiong Ding

Due to temperature differences, heating non-uniformity, and sensor drift, the measurements of differential scanning calorimetry (DSC) usually require calibration; however, traditional calibration methods are difficult to apply under different experimental conditions. To solve the problem, a neural network-based calibration method is proposed in this article. First, a second-order heat transfer model of DSC is established, and its temperature difference is calculated using the sapphire. Second, a neural network is developed to model the relationship between the experimental and model-based temperature differences. Finally, the neural network is trained on the experimental data. The resulting model is then validated using experimental data obtained under different conditions. The results demonstrate that the machine-learning-based calibration method significantly improves the efficiency and accuracy of DSC calibration.

由于温度差异、加热不均匀性和传感器漂移，差示扫描量热法（DSC）的测量通常需要校准；然而，传统的标定方法难以适用于不同的实验条件。为了解决这一问题，本文提出了一种基于神经网络的标定方法。首先，建立DSC的二阶传热模型，利用蓝宝石计算DSC的温差；其次，建立了一个神经网络来模拟实验和模型温差之间的关系。最后，利用实验数据对神经网络进行训练。然后用不同条件下得到的实验数据对所得模型进行验证。结果表明，基于机器学习的DSC标定方法显著提高了DSC标定的效率和精度。

引用次数: 0

Testing and analysis of thermal safety parameters of Unsymmetrical Dimethylhydrazine 非对称二甲肼热安全参数的测试与分析

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-15 DOI: 10.1016/j.tca.2025.180159

Zhen-Li Yang , Wu-Quan Meng , Yan Zhang , Shuang Jing , Ya-Dong Yao

This study investigated the thermal decomposition behavior and safety of Unsymmetrical Dimethylhydrazine (UDMH), which is a highly volatile compound. Differential scanning calorimetry (DSC) was employed to analyze thermal disintegration and derive kinetic parameters using isoconversional methods and nonlinear regression. The DSC test was conducted using high-pressure sealed crucibles. Accelerating rate calorimetry (ARC) assessed adiabatic decomposition, with results corrected for thermal inertia (Φ) to determine adiabatic temperature rise (ΔT_ad) and maximum temperature rise rate (TMR_ad). Corrected ARC data revealed higher thermal risks than measured, leading to a thermal hazard assessment of level III (unacceptable danger) based on thermal runaway criticality classes. UDMH decomposition was consistently exothermic, with peak temperatures exceeding 300 °C, indicating excellent inherent thermal stability.

本文研究了不对称二甲肼（UDMH）的热分解行为和安全性。采用差示扫描量热法（DSC），采用等转换方法和非线性回归方法对其进行热分解分析和动力学参数推导。DSC试验采用高压密封坩埚进行。加速量热法（ARC）评估绝热分解，并对结果进行热惯性校正（Φ），以确定绝热温升（ΔTad）和最大温升速率（TMRad）。校正后的ARC数据显示，热风险高于测量值，导致基于热失控临界等级的热危害评估为III级（不可接受的危险）。UDMH的分解始终是放热的，峰值温度超过300℃，表明了良好的固有热稳定性。

引用次数: 0

Step sequence scenario for the calorimetric evaluation of immature amber age 未成熟琥珀年龄量热评价的步序方案

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-10 DOI: 10.1016/j.tca.2025.180156

Nicolas Delpouve , Eva Laureys , Kylian Hallavant , Elodie Dierickx , Srivaidehi Sripathy , Florian Gilsoul , Didier Neraudeau , Miguel Ángel Ramos , Allisson Saiter-Fourcin

The variety of chemical constitutions and the heterogenous fossilization conditions, added to some circumstantial difficulties in applying the biostratigraphical methodologies, are possible obstacles to the dating of amber. Calorimetric analyses are known as alternatives to complement the conventional dating procedures since they show signatures of maturation by crosslinking, however their interpretation is not straightforward. The method proposed in this study consists in performing consecutive standard and modulated differential scanning calorimetry analyses, along with infrared spectroscopy investigations, to interpretate the thermal signatures in terms of chemical transformations. Twelve ambers differing by their age, botanical origin, and state of alteration, are studied.

The amber maturation is depicted through a calorimetric step sequence assuming that the thermal signatures related to chemical transformations, are delayed, or even cancelled when the amber age increases, and that the observation of the chemical stabilization is anterior to that of the physical aging recovery. To test the relevance of this simple scenario for dating amber, a characteristic transformation parameter is extracted from the calorimetric signals, which leads to the appearance of a global trend for the amber dating, gathering unaltered and untreated materials, within two geological periods, but with a significant data dispersion.

化学成分的多样性和化石条件的不均匀性，加上生物地层学方法应用的一些环境困难，可能成为琥珀测年的障碍。量热分析被认为是传统测年方法的补充，因为它们通过交联显示成熟的特征，但是它们的解释并不简单。本研究提出的方法包括进行连续的标准和调制差示扫描量热分析，以及红外光谱研究，以解释化学转化方面的热特征。12琥珀不同的年龄，植物来源，和状态的变化，进行了研究。假设随着琥珀年龄的增加，与化学转变相关的热特征被延迟甚至取消，并且化学稳定的观察先于物理老化恢复，通过量热步长序列来描述琥珀的成熟过程。为了测试这种简单场景与琥珀定年的相关性，从量热信号中提取了一个特征转换参数，这导致琥珀定年的全球趋势出现，在两个地质时期内收集未改变和未处理的材料，但数据分散明显。

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引用次数: 0

Volumetric and viscometric analysis of aggregation behavior in 2-(Methylamino)ethanol (MAE) + dimethyl sulfoxide (DMSO) non-aqueous solutions 2-（甲氨基）乙醇(MAE) +二甲基亚砜（DMSO）非水溶液中聚集行为的体积和粘度分析

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-08 DOI: 10.1016/j.tca.2025.180154

Jian Ma , Yixiao Wang , Jichao Hu, Gaoqi Han, Lemeng Wang, Huiying Gao, Pan Zhang, Kangrui Li, Dong Fu

This study determined and correlated the density and viscosity of the 2-(methylamino)ethanol (MAE) - dimethyl sulfoxide (DMSO) non-aqueous solution over a temperature range of 298.15 to 323.15 K at atmospheric pressure. The effects of the mass fraction of MAE (w₁), temperature (T) and CO₂ loading (α) on viscosity and density were demonstrated based on of experimental data and calculations. The excess molar volume (

V_{m}^{E}

) and viscosity deviation (Δη) were derived from the experimental data. Furthermore, the

V_{m}^{E}

and Δη were correlated by using the Redlich-Kister equation. The viscosity activation energy and CO₂ diffusion coefficient were calculated and analyzed by utilizing viscosity data. The activation parameters activation enthalpy (ΔΗ*) and activation entropy (ΔS*) were determined using the measured viscosity and density data. This combined study provides insights into intermolecular interactions and transportation characteristics through the observed changes in viscosity and density with composition.

本研究测定了2-（甲氨基）乙醇(MAE) -二甲基亚砜（DMSO）非水溶液在298.15 ~ 323.15 K的常压下的密度和粘度，并进行了相关分析。根据实验数据和计算结果，论证了MAE质量分数（w1）、温度(T)和CO2负荷（α）对粘度和密度的影响。根据实验数据导出了超摩尔体积（VmE）和粘度偏差（Δη）。此外，VmE和Δη通过使用Redlich-Kister方程进行相关。利用黏度数据，计算并分析了黏度活化能和CO2扩散系数。活化参数活化焓（ΔΗ*）和活化熵（ΔS*）由粘度和密度测量数据确定。这项联合研究通过观察到的粘度和密度随组成的变化，提供了分子间相互作用和运输特性的见解。

{"title":"Volumetric and viscometric analysis of aggregation behavior in 2-(Methylamino)ethanol (MAE) + dimethyl sulfoxide (DMSO) non-aqueous solutions","authors":"Jian Ma , Yixiao Wang , Jichao Hu, Gaoqi Han, Lemeng Wang, Huiying Gao, Pan Zhang, Kangrui Li, Dong Fu","doi":"10.1016/j.tca.2025.180154","DOIUrl":"10.1016/j.tca.2025.180154","url":null,"abstract":"<div><div>This study determined and correlated the density and viscosity of the 2-(methylamino)ethanol (MAE) - dimethyl sulfoxide (DMSO) non-aqueous solution over a temperature range of 298.15 to 323.15 K at atmospheric pressure. The effects of the mass fraction of MAE (<em>w</em><sub>1</sub>), temperature (<em>T</em>) and CO<sub>2</sub> loading (<em>α</em>) on viscosity and density were demonstrated based on of experimental data and calculations. The excess molar volume (<span><math><msubsup><mi>V</mi><mrow><mi>m</mi><mspace></mspace></mrow><mrow><mspace></mspace><mi>E</mi></mrow></msubsup></math></span>) and viscosity deviation (<em>Δη</em>) were derived from the experimental data. Furthermore, the <span><math><msubsup><mi>V</mi><mrow><mi>m</mi><mspace></mspace></mrow><mrow><mspace></mspace><mi>E</mi></mrow></msubsup></math></span> and <em>Δη</em> were correlated by using the Redlich-Kister equation. The viscosity activation energy and CO<sub>2</sub> diffusion coefficient were calculated and analyzed by utilizing viscosity data. The activation parameters activation enthalpy (Δ<em>Η*</em>) and activation entropy (Δ<em>S*</em>) were determined using the measured viscosity and density data. This combined study provides insights into intermolecular interactions and transportation characteristics through the observed changes in viscosity and density with composition.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"754 ","pages":"Article 180154"},"PeriodicalIF":3.5,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145334752","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 thermal decomposition characteristics and thermal safety of TKX-50-based multicomponent energetic materials 基于tkx -50的多组分含能材料热分解特性及热安全性研究

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-08 DOI: 10.1016/j.tca.2025.180153

Wenyu Xu , Chunlan Jiang , Zaicheng Wang , Ye Zhang , Yubiao Wei , Wenxiang Li , Jiankui Guo

Novel nitrogen-rich ionic salt energetic material, 5,5′-bitetrazole-1,1′-diol dihydroxylamine salt (TKX-50) has been widely concerned in safety ammunition field. In this paper, non-isothermal thermal analysis and adiabatic ARC experiments are conducted on TKX-50-based multi-component explosive TMCE (TKX-50/CL-20/AP/Al/binder=15/10/32/37/6), and the thermal decomposition characteristics of TMCE are explored. The results indicate that the initial thermal decomposition temperature and the peak decomposition temperatures of TMCE drop dramatically due to the component synergistic interaction. Confinement and oxygen-enriched environments facilitate thermal runaway in TMCE. Based on thermal analysis findings, the Self-Accelerating Decomposition Temperature (SADT) of TMCE was calculated. The heating process of the small-scale cook-off device was calculated and experimentally validated with reaction time errors below 3%. These findings enable thermal safety prediction for TMCE-loaded warheads and provide critical references for engineering applications and formulation design of TKX-50-based energetic materials.

新型富氮离子盐含能材料5,5′-双四唑-1,1′-二醇二羟胺盐（TKX-50）在安全弹药领域受到广泛关注。本文对基于TKX-50的多组分炸药TMCE （TKX-50/CL-20/AP/Al/粘结剂=15/10/32/37/6）进行了非等温热分析和绝热电弧实验，探讨了TMCE的热分解特性。结果表明，由于组分间的协同作用，TMCE的初始热分解温度和峰值分解温度显著下降。约束和富氧环境有利于TMCE的热失控。根据热分析结果，计算了TMCE的自加速分解温度（SADT）。对该装置的加热过程进行了计算和实验验证，反应时间误差在3%以内。这些研究结果为tkx -50型含能材料的工程应用和配方设计提供了重要参考。

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引用次数: 0

Green deep eutectic solvents (DESs) as a sustainable solution for thermal stabilization and flame retardancy of key bioplastic - polylactide 绿色深共晶溶剂（DESs）作为一种可持续的解决方案，用于热稳定和阻燃的关键生物塑料-聚乳酸

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-08 DOI: 10.1016/j.tca.2025.180155

Tomasz M. Majka , Szczepan Bednarz , Krzysztof Pielichowski

This work demonstrates that green deep eutectic solvents can act as efficient thermal stabilizers and flame retardants for an important biopolymer - polylactide. This important bioplastic is a flammable material and this feature limits its application potential in replacing synthetic polymers. In our work, selected Deep Eutectic Solvents (DESs), such as magnesium stearate:eugenol (MS:EU), zinc stearate:eugenol (ZS:EU), oxalic acid:choline chloride (OA:CCl), were adsorbed onto the surface of montmorillonite (MMT). The obtained MMT-DES hybrids were then applied as additives for polylactide (PLA) utilizing an easily upscaled extrusion process. Notably, among the MMT-DES hybrids, the MMT-OA:CCl hybrid exhibited the greatest thermal stability, as well as it showed 93 % lower flammability than pure filler. Thermogravimetric analysis of PLA/DES and PLA/MMT-DES composites allowed us to rank these materials in terms of thermal stability using two different criteria - indices comparison and Overall Thermal Stabilization Effect (OSE). In both cases, the highest thermal stability was achieved by PLA/OA:CCl. Finally, a 34 % reduction in flammability was achieved with the MMT-DES hybrid, while the use of DES alone resulted in a still remarkable 20 % reduction. The obtained results show the vast potential of green DES to improve the performance of biopolymers that play a growing role in sustainable development.

该研究表明，绿色深共晶溶剂可以作为一种重要的生物聚合物聚乳酸的有效热稳定剂和阻燃剂。这种重要的生物塑料是一种可燃材料，这一特性限制了它在替代合成聚合物方面的应用潜力。研究了硬脂酸镁：丁香酚（MS:EU）、硬脂酸锌：丁香酚（ZS:EU）、草酸：氯化胆碱（OA:CCl）等深度共晶溶剂（DESs）在蒙脱土（MMT）表面的吸附。然后利用一种易于升级的挤出工艺将得到的MMT-DES杂化物用作聚乳酸（PLA）的添加剂。值得注意的是，在MMT-DES混合物中，MMT-OA:CCl混合物表现出最大的热稳定性，其可燃性比纯填料低93%。对PLA/DES和PLA/MMT-DES复合材料的热重分析使我们能够使用两个不同的标准-指数比较和总体热稳定效应(OSE) -对这些材料的热稳定性进行排名。在这两种情况下，PLA/OA:CCl获得了最高的热稳定性。最后，MMT-DES混合物的可燃性降低了34%，而单独使用DES的可燃性仍然降低了20%。所得结果表明，绿色DES在改善生物聚合物性能方面具有巨大潜力，在可持续发展中发挥着越来越大的作用。

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引用次数: 0

The properties and transformation of related products for potassium fixing in the interactions between the rice straw ash and NH4H2PO4 and Ca(H2PO4)2 稻草灰与NH4H2PO4、Ca(H2PO4)2相互作用中固钾相关产物的性质及转化

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-10-03 DOI: 10.1016/j.tca.2025.180150

Weixue Xiang, Tinggui Yan, Yunqi Wu, Peixu Zhu, Nanxi Luo, Banglian Tang, Miao Luo

NH₄H₂PO₄ (ADP) and Ca(H₂PO₄)₂ (CPM) were used to reduce potassium emissions in rice straw ash (RSA), but the interactions between additives and RSA and the resulting transformations were unclear. In this work, thermogravimetric analysis identified temperature windows for interactions between the additives and RSA. ³¹PNMR and XRD distinguished the resulting phosphate species. Potassium emissions were reduced by 9.26 kg/t with ADP and 4.77 kg/t with CPM. Additives increased both NH₄Ac-soluble and insoluble potassium fractions. The conversion of KCl to water-soluble K-phosphate occurred between 200-450 °C, a range previously overlooked due to only minor changes in water-soluble fraction up to 700 °C. NH₄Ac-soluble potassium species included K₄Ca(PO₄)₂ and K₂CaP₂O₇, while insoluble species included K-aluminosilicate, K-silicate and Ca₉MgK(PO₄)₇. These solubility distinctions provide new insights for understanding the transformation of P-containing complexes, though further investigation into the thermodynamic and kinetic factors governing these formations is needed.

采用NH4H2PO4 （ADP）和Ca(H2PO4)2 （CPM）对水稻秸秆灰分（RSA）中的钾排放进行了降低，但添加剂与RSA之间的相互作用及其转化效果尚不清楚。在这项工作中，热重分析确定了添加剂和RSA之间相互作用的温度窗口。pnmr和XRD鉴定了所得磷酸盐的种类。ADP和CPM分别减少了9.26 kg/t和4.77 kg/t的钾排放量。添加剂提高了nh4 ac溶性和不溶性钾的分数。KCl向水溶性k -磷酸盐的转化发生在200-450°C之间，这一范围以前被忽视了，因为高达700°C的水溶性部分只有微小的变化。NH₄ac可溶性钾品种包括K₄Ca（PO₄）₂和K₂CaP₂O₇，而不溶性钾品种包括K-铝硅酸盐、K-硅酸盐和Ca₉MgK（PO₄）₇。这些溶解度差异为理解含p配合物的转化提供了新的见解，尽管还需要进一步研究控制这些形成的热力学和动力学因素。

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引用次数: 0