Applied Clay Science最新文献_第5页

Development of free flowing granular hybrid functionalized clay sorbent filters for chromium removal from waste water 开发用于去除废水中铬的自由流动颗粒混合功能化粘土吸附剂过滤器

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-10-09 DOI: 10.1016/j.clay.2024.107591

Rothish R. Nair , Sayoojya P. Sathyan , K.P. Prathish

Chromium (VI) contamination in water resources at industrial sites poses significant environmental and health risks. Conventional sorbents often suffer from limitations such as clogging, back pressure, poor kinetics, and challenges in coupling with flow systems and regeneration. This study focuses on developing, characterizing, and applying free-flowing granular (FFG) amidoxime-functionalized montmorillonite (Mt) clay sorbents (AO-Mt-H-C) to enhance chromium (VI) removal from contaminated waste water. Batch adsorption experiments demonstrated that AO-Mt-H-C outperformed montmorillonite clay modified with quaternary ammonium alone (Mt-H-C), achieving a Cr (VI) removal efficiency of 50.6 mg g⁻¹ compared to 44.3 mg g⁻¹, due to the synergistic interactions of quaternary ammonium and amidoxime functionalities. To address the limitations of conventional sorbents, such as clogging and poor kinetics, an FFG filter column was developed and tested, showing effective Cr (VI) removal across various water sources with minimal interference in drinking and groundwater. In industrial wastewater with higher matrix loads, over 99 % removal efficiency was achieved with a 25 % increase in sorbent dosage. Desorption and reusability assessments confirmed the AO-Mt-H-C's effectiveness across three cycles. Mathematical modelling using Thomas and Yoon–Nelson equations supported the design of customized treatment systems. Scalability was demonstrated by treating 1.6 m³ of textile industrial effluents (100 mg L⁻¹ Cr (VI)) with quantitative removal efficiency (>99.5 %). This study illustrates that the hybrid functionalization and free-flowing granulation of clay sorbent materials significantly enhance Cr (VI) removal, providing valuable insights for advanced water pollution mitigation and environmental sustainability.

工业场地水资源中的铬（VI）污染对环境和健康构成了重大风险。传统的吸附剂往往存在堵塞、背压、动力学性能差等局限性，在与流动系统耦合和再生方面也面临挑战。本研究的重点是开发、表征和应用自由流动颗粒（FFG）脒氧肟功能化蒙脱石（Mt）粘土吸附剂（AO-Mt-H-C），以提高受污染废水中铬（VI）的去除率。批量吸附实验表明，AO-Mt-H-C 的性能优于单独用季铵盐改性的蒙脱石粘土（Mt-H-C），由于季铵盐和脒肟官能团的协同作用，AO-Mt-H-C 对六价铬的去除率达到 50.6 mg g-1，而单独用季铵盐改性的蒙脱石粘土对六价铬的去除率为 44.3 mg g-1。为解决传统吸附剂堵塞和动力学性能差等局限性，开发并测试了一种 FFG 过滤柱，结果表明该过滤柱可有效去除各种水源中的六（Cr），对饮用水和地下水的干扰极小。在基质负荷较高的工业废水中，吸附剂用量增加 25%，去除率超过 99%。解吸和可重复使用性评估证实了 AO-Mt-H-C 在三个周期内的有效性。使用托马斯和尹-尼尔森方程建立的数学模型为定制处理系统的设计提供了支持。通过处理 1.6 立方米的纺织工业废水（100 毫克/升-1 Cr (VI)），定量去除效率（99.5%）证明了其可扩展性。这项研究表明，粘土吸附剂材料的混合功能化和自由流动造粒可显著提高对六价铬的去除率，为先进的水污染缓解和环境可持续性提供了宝贵的见解。

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引用次数: 0

Research on the corrosion protection of in-situ prepared LiAl layered double hydroxides on AZ31 Mg alloy under standard atmospheric pressure and low temperature 标准大气压和低温条件下原位制备的 LiAl 层状双氢氧化物对 AZ31 Mg 合金的腐蚀保护研究

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-10-04 DOI: 10.1016/j.clay.2024.107585

Liyan Wang , Keqi Huang , Zi Yang , Rudolph Buchheit , Zhiyuan Feng

This work successfully prepared LiAl LDHs coatings on AZ31 Mg alloy under standard atmospheric pressure and low temperature. The whole process did not require a hydrothermal autoclave reactor and high pressure. Electrochemical test results showed that the coating was able to provide good corrosion protection performance. The LiAl LDHs coatings provided a large low-frequency impedance on AZ31. When the treatment time was 24 h, the maximum |Z|_0.01Hz at pH = 12 was 5.14 × 10⁴ Ω∙cm², which is more than an order of magnitude higher than the |Z|_0.01Hz of 1.81 × 10³ Ω∙cm² for the bare sample. Under the same treatment conditions, the potentiodynamic polarization test results showed that the LiAl LDHs coated samples had a lower corrosion current density and a higher breakdown potential. The i_corr was 1.78 × 10⁻⁷ A/cm² and E_br was −0.82 V_SCE compared to the Mg substrate (i_corr of 1.13 × 10⁻⁵ A/cm² and E_br of −1.53 V_SCE). Additionally, LiAl LDHs coatings also had a significant inhibitory effect on cathodic hydrogen evolution, providing targeted protection to the cathodic areas.

这项研究在标准大气压和低温条件下，成功地在 AZ31 Mg 合金上制备了 LiAl LDHs 涂层。整个过程不需要水热高压釜反应器和高压。电化学测试结果表明，涂层具有良好的防腐蚀性能。LiAl LDHs 涂层在 AZ31 上产生了较大的低频阻抗。当处理时间为 24 小时时，pH = 12 时的最大|Z|0.01Hz 为 5.14 × 104 Ω∙cm2，比裸样品的|Z|0.01Hz（1.81 × 103 Ω∙cm2）高出一个数量级以上。在相同的处理条件下，电位极化测试结果表明，锂铝 LDHs 涂层样品的腐蚀电流密度较低，击穿电位较高。与镁基底（icorr 为 1.13 × 10-5 A/cm2 和 Ebr 为 -1.53 VSCE）相比，icorr 为 1.78 × 10-7 A/cm2 和 Ebr 为 -0.82 VSCE。此外，锂铝 LDHs 涂层对阴极氢演化也有显著的抑制作用，为阴极区域提供了有针对性的保护。

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引用次数: 0

Mitigating desiccation cracking in bentonite using novel microencapsulated phase change materials 利用新型微胶囊相变材料缓解膨润土中的干燥开裂现象

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-10-03 DOI: 10.1016/j.clay.2024.107586

Jiaxin Liu , Chentao Zhu , Xiong Yu (Bill) , Chanjuan Han

Bentonite, widely employed in geotechnical projects, faces a pressing challenge in addressing desiccation cracking. Leveraging its high latent heat, microencapsulated phase change material (microPCM) holds promise in ameliorating this issue. This study pioneers the application of microPCM as an additive to enhance bentonite's resistance to cracking. Employing an automated measurement platform, a series of desiccation cracking tests were conducted on bentonite blends with varying microPCM contents. Techniques including mercury intrusion porosimetry, scanning electron microscopy, digital image processing, infrared thermography, and particle image velocimetry, were employed to elucidate these mechanisms. Quantitative metrics were defined and meticulously analyzed across samples with different microPCM ratios. Additionally, qualitative and quantitative assessments of pore structure features were conducted. Key findings demonstrate that the incorporation of microPCM can delay evaporation by up to 33 % (at a microPCM mass fraction of 15 %) while intensifying volumetric contraction. This delay effectively postpones crack initiation and doubles crack propagation duration. However, microPCM agglomeration tendencies leading to formation of additional cavities may act as initial defects in the bentonite. This study not only illuminates the potential of microPCM as an effective additive in enhancing bentonite's resistance to desiccation cracking but also identifies associated challenges, thus paving the way for further innovative research.

膨润土被广泛应用于岩土工程中，但在解决干燥开裂方面却面临着紧迫的挑战。利用膨润土的高潜热，微胶囊相变材料（microPCM）有望改善这一问题。本研究开创性地将微胶囊相变材料用作添加剂，以增强膨润土的抗开裂性。采用自动化测量平台，对不同微 PCM 含量的膨润土混合物进行了一系列干燥开裂测试。为了阐明这些机理，我们采用了汞侵入孔隙度测定法、扫描电子显微镜、数字图像处理、红外热成像和粒子图像测速仪等技术。对不同微 PCM 比率的样品进行了定量指标定义和细致分析。此外，还对孔隙结构特征进行了定性和定量评估。主要研究结果表明，加入 microPCM 可使蒸发延迟 33%（当 microPCM 的质量分数为 15%时），同时加强体积收缩。这种延迟可有效推迟裂纹的产生，并将裂纹扩展的持续时间延长一倍。不过，微 PCM 的团聚趋势会导致形成额外的空腔，这可能会成为膨润土的初始缺陷。这项研究不仅揭示了微 PCM 作为一种有效添加剂在增强膨润土抗干燥开裂能力方面的潜力，还指出了相关的挑战，从而为进一步的创新研究铺平了道路。

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引用次数: 0

Early-age shrinkage behavior of cement mixtures regulated with metakaolin-based internal conditioning 用偏高岭土内调节剂调节水泥混合物的早龄收缩行为

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-10-03 DOI: 10.1016/j.clay.2024.107583

Dayou Luo, Jianqiang Wei

Shrinkage occurs in concrete during its hardening and strength gain process leading to undesired deformation, cracking, and decreases in strength and durability. While metakaolin-based internal conditioning (MIC) has been validated as a promising technique for modifying cement and mitigating alkali-silica reactions in concrete, its impact on the early-age shrinkage behavior of cement remains unexplored. This study delves into the effects of MIC and its coupling with lithium on the chemical shrinkage, autogenous shrinkage, and drying shrinkage of portalnd cement incorporating 30 % metakaolin with varying degrees of saturation (50 %, 75 %, and 100 %). The results indicate that the hydration of cement can be substantially enhanced by MIC with 29.0 % more heat released and a 32.3 % decrease in calcium hydroxide content. As a result of the enhanced hydration, cement with MIC yielded increased chemical shrinkage. Compared with dry MK, the autogenous shrinkage and drying shrinkage of cement were decreased by 38.0 % and 11.0 %, respectively, in the presence of MIC. A synergistic effect between MIC and lithium was suggested by the higher efficacy in suppressing autogenous shrinkage.

混凝土在硬化和强度增加的过程中会产生收缩，从而导致不必要的变形、开裂以及强度和耐久性下降。虽然偏高岭土基内部调节（MIC）已被证实是改性水泥和减轻混凝土中碱-硅反应的有效技术，但其对水泥早期龄期收缩行为的影响仍有待探索。本研究深入探讨了 MIC 及其与锂的耦合作用对掺入 30%偏高岭土且饱和度不同（50%、75% 和 100%）的 portalnd 水泥的化学收缩、自生收缩和干燥收缩的影响。结果表明，MIC 能显著提高水泥的水化效果，放出的热量增加 29.0%，氢氧化钙含量减少 32.3%。由于水化作用增强，添加了 MIC 的水泥的化学收缩率也随之增加。与干燥的 MK 相比，在 MIC 的作用下，水泥的自生收缩率和干燥收缩率分别降低了 38.0 % 和 11.0 %。MIC 和锂的协同效应被认为在抑制自生收缩方面具有更高的功效。

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引用次数: 0

Luminescence Boosting after adding Quaternary ammonium/Phosphine Cations to Europium (III) Laponite Clay 向铕 (III) 皂土中添加季铵/膦阳离子后的发光增强效果

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-10-01 DOI: 10.1016/j.clay.2024.107584

Gaokuo Du, Huanrong Li, Zixuan Li, Xinchi Ye, Yige Wang

Quaternary ammonium/phosphine cations added to the platelets of Laponite clay can lead to the remarkable enhancement of luminescence efficiency of the europium (III) β-diketonate complex. The mechanism for the luminescence boosting by the organic cations was elucidated by comparing two diketonate ligands with different pKa and the pH value of the selected organic salts based on the stationery and time resolved spectroscopy. It can be concluded as that the presence of the quaternary ammonium or quaternary phosphine cations helps to form Eu³⁺-β-diketonate complexes with high coordination numbers by decreasing the acidic sites on the platelet surface of laponite clay. Our work further strengthens the simplicity and generalization of obtaining highly luminescent materials and provides a unique insight into the function of the quaternary ammonium/quaternary phosphine cations in boosting the luminescence of lanthanide-based organic-inorganic hybrid materials.

在皂石粘土的平板中添加季铵/膦阳离子可显著提高β-二酮酸铕（III）配合物的发光效率。通过比较两种具有不同 pKa 值的二酮酸配体以及所选有机盐的 pH 值，并根据静态光谱和时间分辨光谱，阐明了有机阳离子促进发光的机制。可以得出这样的结论：季铵或季膦阳离子的存在有助于通过减少青石粘土小板表面的酸性位点来形成高配位数的 Eu3+-β- 二酮酸配合物。我们的工作进一步增强了获得高发光材料的简易性和通用性，并对季铵/季膦阳离子在促进镧系元素有机-无机杂化材料发光方面的功能提供了独特的见解。

引用次数: 0

Efficient transformation of CO2 into α-alkylidene cyclic carbonates over Cu0/Cu+ derived from CuAl layered double hydroxide/reduced graphene oxide hybrid 在源自 CuAl 层状双氢氧化物/还原氧化石墨烯混合物的 Cu0/Cu+ 上将 CO2 高效转化为 α-亚烷基环碳酸盐

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-09-28 DOI: 10.1016/j.clay.2024.107581

Zheng Wang , Yue Qiu , Baoyu Zou , Deke Wang , Zifei Gao , Xuanheng Zhang , Juanjuan Ma , Lin Liu , Chao Liu , Zhiwei Tong

A simple liquid-phase co-precipitation method was used to achieve a good dispersion of CuAl layered double hydroxide (CuAl-LDH) on the surface of graphene oxide (GO), and Cu²⁺ in the lattice of CuAl-LDH was in-situ reduced to Cu⁰ and Cu⁺ species, resulting in the preparation of R-CuAl-LDH/rGO catalyst. It could effectively catalyze the cyclization of CO₂ and propargylic alcohols under mild conditions (50 °C and 1 bar), and the yield exceeded 99 % within only 40 min. Systematic characterization revealed that two-dimensional LDH nanosheets were grown on the rGO surface in an irregular orientation, leading to a higher specific surface area and more abundant surface active sites. Meanwhile, the synergistic catalysis of Cu⁰ and Cu⁺ dual-active sites greatly enhanced the catalytic efficiency. In addition, the catalyst had excellent recycling properties with no significant loss of activity after 5 cycles of continuous operation.

采用简单的液相共沉淀方法在氧化石墨烯（GO）表面实现了CuAl层状双氢氧化物（CuAl-LDH）的良好分散，并将CuAl-LDH晶格中的Cu2+原位还原为Cu0和Cu+物种，从而制备了R-CuAl-LDH/rGO催化剂。它能在温和的条件下（50 °C 和 1 bar）有效催化 CO2 和丙炔醇的环化反应，仅在 40 分钟内产率就超过了 99%。系统表征结果表明，二维 LDH 纳米片以不规则取向生长在 rGO 表面，从而获得了更高的比表面积和更丰富的表面活性位点。同时，Cu0 和 Cu+ 双活性位点的协同催化作用大大提高了催化效率。此外，该催化剂还具有优异的回收性能，在连续运行 5 个周期后活性没有明显降低。

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引用次数: 0

Compressibility of a binary bentonite-based mixture with particular emphasis on pellet orientation 二元膨润土基混合物的可压缩性，特别强调球团取向

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-09-27 DOI: 10.1016/j.clay.2024.107575

Arisleidy Mesa-Alcantara , Enrique Romero , Joel Torres-Serra , Nadia Mokni

Binary mixtures of Wyoming-type bentonite, consisting of 80 % mass high-density pellets and 20 % granular bentonite, are currently considered candidate materials for the French concept of vertical sealing systems for deep and long-term disposal of radioactive wastes. At low emplacement water contents, the hydro-mechanical behaviour is primarily controlled by contact forces between pellets, forming a coarse grain-supported structure over which granular bentonite is poured. These pellets were uniaxially compacted at elevated stresses to reach high dry densities. Subsequent pellet unloading resulted in anisotropic features due to fissuring and delamination, followed by water absorption. This study investigated compressibility changes upon loading under laterally confined conditions of a well-oriented pellet-supported structure, mimicking the setup of the in situ VSEAL 1 experiment at Tournemire (France). Two pellet orientations at the same dry density and coordination number of pellet contacts were examined in a pure pellet skeleton and a mixture to account for potential heterogeneity during pouring. A discrete element method was used to simulate the compression results with pellets represented as a clump with a heterogeneous void ratio distribution due to fissuring. These simulations were instrumental in understanding the important anisotropic deformation properties of pellet-supported structures under two distinct orientations.

怀俄明型膨润土的二元混合物由 80%的高密度球团和 20%的颗粒膨润土组成，目前被认为是法国为深层和长期处置放射性废料而设计的垂直密封系统的候选材料。在填充水含量较低的情况下，水力机械性能主要由颗粒之间的接触力控制，形成一个粗颗粒支撑结构，颗粒膨润土被浇注在该结构上。这些球团在较高应力下进行单轴压实，以达到较高的干密度。随后的颗粒卸载会导致各向异性特征，这是由于裂缝和分层造成的，然后是吸水。本研究模仿图尔奈米尔（法国）VSEAL 1 现场实验的设置，对取向良好的颗粒支撑结构在横向约束条件下加载时的可压缩性变化进行了研究。对纯颗粒骨架和混合物中相同干密度和协调颗粒接触数量的两种颗粒取向进行了研究，以考虑浇注过程中潜在的异质性。使用离散元素法模拟了压缩结果，球团表现为一团，由于裂解，空隙率分布不均匀。这些模拟有助于了解颗粒支撑结构在两种不同方向下的重要各向异性变形特性。

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引用次数: 0

Chemometrics of meta-clay FT-IR spectra: From heating temperature estimation to meta-clay identification 元粘土傅立叶变换红外光谱的化学计量学：从加热温度估算到元粘土鉴定

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-09-26 DOI: 10.1016/j.clay.2024.107579

Matthieu Ménager

In this research, chemometric tools (Partial Least-Squares Regression, Principal Component Regression, Linear Discriminant Analysis for example) allowed estimating firing temperatures and to identify the type of meta-clay based on their infrared spectra.

The 3 min phases observed in clay thermal degradation were: (i) a dehydroxylation reaction between 400 and 500–600 °C leading to the formation of a non-crystalline meta-clay, (ii) a continuous thermal degradation reaction of the meta-clay involving the SiO bonds between 500 and 850 °C, (iii) the formation of secondary silicates above 850 °C.

The 10 Latent Variables of the Partial Least-Squares Regression model led to accurate predictions (Root Mean Squared Error of Prediction = 66.6) and provided a good correlation between predicted and actual temperatures, without any estimation bias related to the type of clay, the presence of other minerals or iron concentration. These models give greater importance to the infrared absorption bands of the bonds involved in thermal degradation: Si-O-Si (1026 and 461

c m^{- 1}

), Si-O-Al (526

c m^{- 1}

), SiO or AlO (1095

c m^{- 1}

), and infrared bands resulting from the formation of meta-clays (486 et 562

c m^{- 1}

).

Finally, a Linear Discriminant Analysis model is proposed in order to identify the type of meta-clay between different types of meta-kaolinites, meta-nacrite and meta-smectite in 96 % of cases. The meta-clays produced by the firing of halloysite, dickite and kaolinite were too close in terms of infrared spectra to be distinguished.

在这项研究中，利用化学计量学工具（例如部分最小二乘回归、主成分回归、线性判别分析）可以估计烧成温度，并根据红外光谱确定元粘土的类型：在粘土热降解过程中观察到的 3 个分阶段是：(i) 400 至 500-600 °C 之间的脱羟基反应，导致形成非结晶的元粘土；(ii) 500 至 850 °C 之间元粘土涉及 SiO 键的连续热降解反应；(iii) 850 °C 以上形成次生硅酸盐。部分最小二乘法回归模型的 10 个潜在变量得出了准确的预测结果（预测的均方根误差 = 66.6），并在预测温度和实际温度之间提供了良好的相关性，没有任何与粘土类型、其他矿物的存在或铁浓度有关的估计偏差。这些模型更重视参与热降解的键的红外吸收带：最后，提出了线性判别分析模型，以便在 96% 的情况下识别不同类型的元高岭土、元黑云母和元闪长岩之间的元粘土类型。从红外光谱上看，焙烧埃洛石、屌石和高岭石产生的元粘土过于接近，无法区分。

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引用次数: 0

Thermal evolution of a kaolin: Quantitative phase analysis and assessment of the thermal markers of the Provins clay 高岭土的热演化：普罗旺斯粘土的定量相分析和热标记评估

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-09-26 DOI: 10.1016/j.clay.2024.107582

Gilles Wallez , Anne Bouquillon , Yvan Coquinot

The thermal evolution of a kaolin from Provins, France, has been monitored using X-ray diffraction and Rietveld analysis over the 950–1200 °C range. The quantitative assessment of the evolution of mullite, cristobalite and the transient spinel was made possible by the recent resolution of the crystal structure of the latter phase, thus leading to investigate and explain its two-step nucleation mechanism. The progressive transformation of anatase (TiO₂) into rutile was measured the same way, along with the mean crystallite size and cell parameters evolution of mullite. These transformations were then discussed in order to propose relevant thermal markers likely to be used to assess the thermal treatments undergone by kaolinite-based ceramics. In the present case, the rutile/anatase ratio turned to be relevant up to 1100 °C, mullite's a parameter in the domain of crystallization of primary mullite (950–1150 °C), while the mullite/spinel ratio and mullite crystallite size make reliable thermal markers in the domain of secondary mullite (1100–1200 °C), thus covering a wide range of temperature likely to be used in traditional earthenware making.

利用 X 射线衍射和里特维尔德分析法监测了法国普罗旺斯一种高岭土在 950-1200 °C 范围内的热演化过程。对莫来石、霞石和瞬变尖晶石演变过程的定量评估得益于最近对后一阶段晶体结构的解析，从而有助于研究和解释其两步成核机制。用同样的方法测量了锐钛矿（TiO2）向金红石的逐步转变，以及莫来石的平均晶粒尺寸和晶胞参数演变。然后对这些转变进行了讨论，以便提出可能用于评估高岭石基陶瓷热处理的相关热标记。在目前的情况下，金红石/金红石比率在 1100 °C以下具有相关性，莫来石是初级莫来石结晶领域（950-1150 °C）的一个参数，而莫来石/尖晶石比率和莫来石晶粒大小则是次级莫来石领域（1100-1200 °C）的可靠热标记，从而涵盖了传统陶器制造中可能使用的广泛温度范围。

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引用次数: 0

One-pot synthesis of MgAl layered double hydroxides (LDH) from weathered tropical soils 从热带风化土壤中一次合成 MgAl 层状双氢氧化物 (LDH)

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2024-09-25 DOI: 10.1016/j.clay.2024.107580

Elden Willems , Niels Van Velthoven , Erik Smolders , Maarten Everaert

Nutrient recycling is imperative for moving towards a circular economy. Layered double hydroxides (LDH) have been suggested as materials of interest for phosphorus (P) recycling, as they can selectively recover P from liquid waste streams and can be used as efficient P fertilisers in agriculture. Local P recycling with LDH can be particularly valuable for smallholder farmers with limited access to fertilisers, e.g. in tropical regions. However, conventional LDH production relies on external sources of Al³⁺ for the synthesis of MgAl LDH. The present work proposed a new fertiliser technology based on LDH partly synthesized at room temperature with weathered soil as a local and omnipresent source of Al, supplemented with MgO and NaOH. The successful synthesis of LDH via this approach was confirmed by X-ray diffractometry (XRD). The capacity of this LDH to recover P was determined with synthetic P solutions and human urine as a waste model. A chemical desorption test demonstrated the available nature of P sorbed onto the soil-based LDH, which largely outperformed the availability of P sorbed onto the untreated soil. Finally, the fertiliser potential of the soil-based LDH loaded with recycled P was confirmed in a pot trial with rice (Oryza sativa L.) in weathered soil, indicating the combined P fertiliser and liming effect. Taken together, this study presented the proof-of-concept of a novel technology for local P recycling in tropical regions.

要实现循环经济，养分循环利用势在必行。有人建议将层状双氢氧化物（LDH）作为磷（P）回收的相关材料，因为它们可以选择性地从液体废物流中回收 P，并可用作农业中的高效 P 肥料。使用 LDH 在当地进行磷回收，对于热带地区等肥料获取途径有限的小农特别有价值。然而，传统的 LDH 生产依赖外部 Al3+ 来合成 MgAl LDH。本研究提出了一种新的肥料技术，该技术以风化土壤为当地无处不在的 Al 源，辅以氧化镁和 NaOH，在室温下合成部分 LDH。X 射线衍射仪 (XRD) 证实，通过这种方法成功合成了 LDH。这种 LDH 回收 P 的能力是用合成 P 溶液和人尿作为废物模型来测定的。化学解吸试验证明了吸附在土壤 LDH 上的 P 的可用性，其可用性大大超过了吸附在未处理土壤上的 P 的可用性。最后，在对风化土壤中的水稻（Oryza sativa L.）进行的盆栽试验中，证实了含有回收钾的土基 LDH 的肥料潜力，表明其具有钾肥和石灰化的综合效果。综上所述，本研究提出了一种在热带地区进行本地钾回收利用的新型技术的概念验证。

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引用次数: 0