Applied Clay Science最新文献

The effect of anion species in the interlayer of layered double hydroxides on the flame retardancy of composites

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-04-03 DOI: 10.1016/j.clay.2025.107812

Yuze Zhang , Lijuan Li , Nan Chen , Dong Shi , Xuexue Song , Lianmin Ji , Fugen Song

Layered double hydroxides (LDHs) are increasingly being used in polymer flame retardancy, but current developments often overlook the effects of various structural factors on flame suppression effectiveness. These factors are crucial for the design of high-performance flame retardants. To investigate the structure–function relationship between anion species and polymer flame retardancy, MgAl LDHs of BAL, BPL and BSL, intercalated with anions of benzoic acid (BA), benzene hypophosphorous acid (BP) and benzene sulfinic acid (BS), respectively, were synthesised via co-precipitation. Their properties, including flame retardancy, were systemically investigated in this study. Despite their similar structures, with only differing acid species, BAL, BPL and BSL exhibited similar interlayer distances but varied in their intercalation capability, crystallisation, thermal decomposition and surface hydrophobicity. Compared to pure EP, the composites containing LDHs, particularly BSL, performed significantly better in limiting oxygen index, vertical burning and cone calorimeter tests. The improvement can be attributed to the carbonisation and altered decomposition pathways of the composites. All three LDHs seemed to have little impact on the tensile strength and dielectric properties of the composites. The results of this investigation indicate that the acid species can significantly affect both the properties of the LDHs and the composites. Furthermore, sulfinic acid, or the sulfur element in LDHs, may exhibit superior performance in polymer flame retardancy. This provides valuable insight into the structure–function relationship study of LDH-based flame retardants and lays a solid foundation for the design of novel, high-efficiency LDH flame retardants.

{"title":"The effect of anion species in the interlayer of layered double hydroxides on the flame retardancy of composites","authors":"Yuze Zhang , Lijuan Li , Nan Chen , Dong Shi , Xuexue Song , Lianmin Ji , Fugen Song","doi":"10.1016/j.clay.2025.107812","DOIUrl":"10.1016/j.clay.2025.107812","url":null,"abstract":"<div><div>Layered double hydroxides (LDHs) are increasingly being used in polymer flame retardancy, but current developments often overlook the effects of various structural factors on flame suppression effectiveness. These factors are crucial for the design of high-performance flame retardants. To investigate the structure–function relationship between anion species and polymer flame retardancy, Mg<img>Al LDHs of BAL, BPL and BSL, intercalated with anions of benzoic acid (BA), benzene hypophosphorous acid (BP) and benzene sulfinic acid (BS), respectively, were synthesised via co-precipitation. Their properties, including flame retardancy, were systemically investigated in this study. Despite their similar structures, with only differing acid species, BAL, BPL and BSL exhibited similar interlayer distances but varied in their intercalation capability, crystallisation, thermal decomposition and surface hydrophobicity. Compared to pure EP, the composites containing LDHs, particularly BSL, performed significantly better in limiting oxygen index, vertical burning and cone calorimeter tests. The improvement can be attributed to the carbonisation and altered decomposition pathways of the composites. All three LDHs seemed to have little impact on the tensile strength and dielectric properties of the composites. The results of this investigation indicate that the acid species can significantly affect both the properties of the LDHs and the composites. Furthermore, sulfinic acid, or the sulfur element in LDHs, may exhibit superior performance in polymer flame retardancy. This provides valuable insight into the structure–function relationship study of LDH-based flame retardants and lays a solid foundation for the design of novel, high-efficiency LDH flame retardants.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107812"},"PeriodicalIF":5.3,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synergistic effect of high-energy milling and organic intercalation on the kaolin properties and structural evolution

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-04-01 DOI: 10.1016/j.clay.2025.107811

Alexandre Zaccaron , Fabiano Raupp-Pereira , Vitor de Souza Nandi , João C.C. Abrantes , Manuel J. Ribeiro , Adriano Michael Bernardin

Clays are raw materials with a wide range of applications in modern times. They can be used in various industrial applications, from the simplest to the most technological, such as in the ceramic industry to functionalizing components for the intercalation of organic molecules into polymeric matrices. Kaolinitic clays with a 1:1-layer structure is among the most abundant in the Earth's crust and are relatively easy to extract. Therefore, studies aimed at expanding the range of applications through the modification of the microstructure of these clay minerals have increasingly attracted scientific attention. The microstructural alteration of kaolinite through high-energy mechanical action can be an interesting method for mineral functionalization, as it leads to an increase in specific surface area and, consequently, the reactivity of the inorganic solid component. For this reason, this study investigated the effectiveness of the mechanical transformation process using high-purity kaolin, characterized before and after the high-energy milling process using XRF, XRD, DTA/TG, PSD, FTIR, and SEM techniques. The results showed that the milling process significantly altered the kaolinitic microstructure, demonstrating a reduction in particle size under the established experimental conditions, reaching D₉₀ ≤ 1 μm. By obtaining a reactive solid with a significantly increased specific surface area (18× increase through milling), a 2^k factorial experimental design was applied to study some variables of the intercalation process, such as the type of molecule (diaminomethanal - urea and dimethyl sulfoxide - DMSO), stirring time (from 12 to 24 h), and kaolinite mass (varying from 10 to 50 g) in a 100 mL solution. The microstructural characterization results via XRD revealed that the use of DMSO resulted in better efficacy in increasing basal spacing (from 7.2 Å to 11.3 Å with DMSO) and consequently in a possible application with functional groups.

{"title":"Synergistic effect of high-energy milling and organic intercalation on the kaolin properties and structural evolution","authors":"Alexandre Zaccaron , Fabiano Raupp-Pereira , Vitor de Souza Nandi , João C.C. Abrantes , Manuel J. Ribeiro , Adriano Michael Bernardin","doi":"10.1016/j.clay.2025.107811","DOIUrl":"10.1016/j.clay.2025.107811","url":null,"abstract":"<div><div>Clays are raw materials with a wide range of applications in modern times. They can be used in various industrial applications, from the simplest to the most technological, such as in the ceramic industry to functionalizing components for the intercalation of organic molecules into polymeric matrices. Kaolinitic clays with a 1:1-layer structure is among the most abundant in the Earth's crust and are relatively easy to extract. Therefore, studies aimed at expanding the range of applications through the modification of the microstructure of these clay minerals have increasingly attracted scientific attention. The microstructural alteration of kaolinite through high-energy mechanical action can be an interesting method for mineral functionalization, as it leads to an increase in specific surface area and, consequently, the reactivity of the inorganic solid component. For this reason, this study investigated the effectiveness of the mechanical transformation process using high-purity kaolin, characterized before and after the high-energy milling process using XRF, XRD, DTA/TG, PSD, FTIR, and SEM techniques. The results showed that the milling process significantly altered the kaolinitic microstructure, demonstrating a reduction in particle size under the established experimental conditions, reaching D<sub>90</sub> ≤ 1 μm. By obtaining a reactive solid with a significantly increased specific surface area (18× increase through milling), a 2<sup>k</sup> factorial experimental design was applied to study some variables of the intercalation process, such as the type of molecule (diaminomethanal - urea and dimethyl sulfoxide - DMSO), stirring time (from 12 to 24 h), and kaolinite mass (varying from 10 to 50 g) in a 100 mL solution. The microstructural characterization results via XRD revealed that the use of DMSO resulted in better efficacy in increasing basal spacing (from 7.2 Å to 11.3 Å with DMSO) and consequently in a possible application with functional groups.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107811"},"PeriodicalIF":5.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel montmorillonite-based room temperature phosphorescence material by host-guest system

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-31 DOI: 10.1016/j.clay.2025.107799

Yan Zou , Junjie Ding , Libing Liao , Qingfeng Guo , Pengfei Shuai

Organic room temperature phosphorescence (RTP) materials have attracted increasing attention for their advantages such as easy preparation, low toxicity, and low cost. These materials show favorable performance in the fields of bioimaging, solid-state lighting, and anti-counterfeiting. In this paper, a novel RTP material was prepared using modified montmorillonite as host and 4,4′-biphenyldiboronic acid as guest. Under the 290 nm excitation, materials exhibit intense room-temperature phosphorescence centered at around 500 nm with a phosphorescence lifetime of 268 ± 2 ms. The modified MT developed in this work can largely eliminate the phosphorescence quenching effect of Fe^III. Additionally, it provides a more stable and rigid environment for organic molecules, thus suppressing non-radiative transitions and realizing phosphorescence emission. The preparation process of this work has the advantages of low cost and easy operation, providing a new approach for the development of organic RTP materials with a promising application prospect.

引用次数: 0

Size fractionation of montmorillonite colloids through saturated porous media and their heterogeneous contribution to the transport of Pb2+

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-30 DOI: 10.1016/j.clay.2025.107808

Lulu Lu , Xiaochen Peng , Zhiwei Chen , Kunyu Wen , Usman Farooq , Taotao Lu , Zhichong Qi , Weifeng Chen

The size fractionation of colloids is an important process while they migrate through porous media. To date, the information about the contribution of the size fractionation of clay colloids on heavy metal mobility during their co-transport process is limited. Herein, taking montmorillonite as a typical clay mineral, the size fractionation characteristics (> 2.0 μm, 1.2–2.0 μm, 0.45–1.2 μm, 0.1–0.45 μm, and < 0.1 μm) of colloidal montmorillonite particles after passing through saturated sand and their different contribution to Pb²⁺ transport were investigated. The results indicated that the extent of Pb²⁺-mobilizing ability of colloids at pH 7.0 was higher than that at pH 5.0, ascribed to more Pb²⁺ adsorbed to the colloids and greater mobility of colloids at higher pH values. Generally, the contribution of colloid size fractions on Pb²⁺ mobility followed the order of (> 2.0 μm) > (< 0.1 μm) > 0.45–1.2 μm > 0.1–0.45 μm ≈ 1.2–2.0 μm, which depended on the colloid size distribution in the effluents (i.e., the larger proportion of fractions exhibited greater contribution to the enhancement of Pb²⁺ mobility in this work). However, the relative contaminant-mobilizing abilities of different colloid size fractions (obtained by normalizing the fraction-facilitated Pb²⁺ breakthrough with the respective fraction breakthrough) increased with the decrease in colloid size, which stemmed from the relatively higher mobility and greater metal-binding capacities of smaller size fractions. Additionally, the differences in the relative contaminant-mobilizing abilities of different fractions decreased with decreasing sand grain sizes (20–40 mesh (0.425–0.85 mm), 40–60 mesh (0.25–0.425 mm), and 60–80 mesh (0.178–0.25 mm)), which was related to the different mobility of the colloid size fractions. In summary, these findings indicate that size fractionation of natural colloids plays a critical role in heavy metal mobility and retention in groundwater systems.

{"title":"Size fractionation of montmorillonite colloids through saturated porous media and their heterogeneous contribution to the transport of Pb2+","authors":"Lulu Lu , Xiaochen Peng , Zhiwei Chen , Kunyu Wen , Usman Farooq , Taotao Lu , Zhichong Qi , Weifeng Chen","doi":"10.1016/j.clay.2025.107808","DOIUrl":"10.1016/j.clay.2025.107808","url":null,"abstract":"<div><div>The size fractionation of colloids is an important process while they migrate through porous media. To date, the information about the contribution of the size fractionation of clay colloids on heavy metal mobility during their co-transport process is limited. Herein, taking montmorillonite as a typical clay mineral, the size fractionation characteristics (> 2.0 μm, 1.2–2.0 μm, 0.45–1.2 μm, 0.1–0.45 μm, and < 0.1 μm) of colloidal montmorillonite particles after passing through saturated sand and their different contribution to Pb<sup>2+</sup> transport were investigated. The results indicated that the extent of Pb<sup>2+</sup>-mobilizing ability of colloids at pH 7.0 was higher than that at pH 5.0, ascribed to more Pb<sup>2+</sup> adsorbed to the colloids and greater mobility of colloids at higher pH values. Generally, the contribution of colloid size fractions on Pb<sup>2+</sup> mobility followed the order of (> 2.0 μm) > (< 0.1 μm) > 0.45–1.2 μm > 0.1–0.45 μm ≈ 1.2–2.0 μm, which depended on the colloid size distribution in the effluents (i.e., the larger proportion of fractions exhibited greater contribution to the enhancement of Pb<sup>2+</sup> mobility in this work). However, the relative contaminant-mobilizing abilities of different colloid size fractions (obtained by normalizing the fraction-facilitated Pb<sup>2+</sup> breakthrough with the respective fraction breakthrough) increased with the decrease in colloid size, which stemmed from the relatively higher mobility and greater metal-binding capacities of smaller size fractions. Additionally, the differences in the relative contaminant-mobilizing abilities of different fractions decreased with decreasing sand grain sizes (20–40 mesh (0.425–0.85 mm), 40–60 mesh (0.25–0.425 mm), and 60–80 mesh (0.178–0.25 mm)), which was related to the different mobility of the colloid size fractions. In summary, these findings indicate that size fractionation of natural colloids plays a critical role in heavy metal mobility and retention in groundwater systems.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107808"},"PeriodicalIF":5.3,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluating two series of layered double hydroxides in the fight against microorganisms

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-28 DOI: 10.1016/j.clay.2025.107789

Anna Donnadio , Tamara Posati , Livia Ottaviano , Severino Zara , Francesco Fancello , Salvatore Marceddu , Andrea Migliori , Morena Nocchetti

The increasing prevalence of antimicrobial resistance has created a need for the development of innovative antimicrobial strategies beyond traditional antibiotics. Layered double hydroxides, with their tunable chemical composition and controlled ion release capabilities, have emerged as promising candidates for facing multidrug-resistant pathogens. In this study, layered double hydroxides were synthesized using co-precipitation and double microemulsion methods to produce nanoparticles with distinct particle sizes (diameter and thickness) and intercalated anions. Their antimicrobial activity was evaluated against different bacterial and fungal strains, including Staphylococcus aureus and Candida albicans. The results revealed that layered double hydroxides with smaller particle sizes and intercalated bromide anions demonstrated superior antibacterial efficacy, attributable to enhanced ion release and increased interaction with microbial membranes. Notably, layered double hydroxides prepared by double microemulsion and containing Mg(II), Cu(II), Al(III) and bromide anions exhibited the highest antimicrobial activity, highlighting the impact of particle dimensions and intercalated anion properties on performance. This work highlights the potential of layered double hydroxides based materials as versatile antimicrobial agents, offering a sustainable solution to address the challenges of antimicrobial resistance in clinical and environmental applications.

{"title":"Evaluating two series of layered double hydroxides in the fight against microorganisms","authors":"Anna Donnadio , Tamara Posati , Livia Ottaviano , Severino Zara , Francesco Fancello , Salvatore Marceddu , Andrea Migliori , Morena Nocchetti","doi":"10.1016/j.clay.2025.107789","DOIUrl":"10.1016/j.clay.2025.107789","url":null,"abstract":"<div><div>The increasing prevalence of antimicrobial resistance has created a need for the development of innovative antimicrobial strategies beyond traditional antibiotics. Layered double hydroxides, with their tunable chemical composition and controlled ion release capabilities, have emerged as promising candidates for facing multidrug-resistant pathogens. In this study, layered double hydroxides were synthesized using co-precipitation and double microemulsion methods to produce nanoparticles with distinct particle sizes (diameter and thickness) and intercalated anions. Their antimicrobial activity was evaluated against different bacterial and fungal strains, including <em>Staphylococcus aureus</em> and <em>Candida albicans</em>. The results revealed that layered double hydroxides with smaller particle sizes and intercalated bromide anions demonstrated superior antibacterial efficacy, attributable to enhanced ion release and increased interaction with microbial membranes. Notably, layered double hydroxides prepared by double microemulsion and containing Mg(II), Cu(II), Al(III) and bromide anions exhibited the highest antimicrobial activity, highlighting the impact of particle dimensions and intercalated anion properties on performance. This work highlights the potential of layered double hydroxides based materials as versatile antimicrobial agents, offering a sustainable solution to address the challenges of antimicrobial resistance in clinical and environmental applications.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107789"},"PeriodicalIF":5.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanical activation of kaolinite for sodalite synthesis under mild conditions

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-27 DOI: 10.1016/j.clay.2025.107796

Yi Liu, Baifa Zhang, Mohammad Fahimizadeh, Ting Yu, Zhou Ou, Zhineng Peng, Peng Yuan

This study investigated the effects of mechanical activation on the transformation of kaolinite to sodalite under mild conditions. The sodalite prepared via alkaline leaching of kaolinite under different milling times, alkaline concentrations, and leaching times was studied. The prepared zeolites were physically, chemically, and morphologically characterized. The results show that ball milling can significantly reduce the particle size and increase the specific surface area of kaolinite. Highly crystalline sodalite (Na₈Al₆Si₆O₂₄(OH)₂) can be prepared from kaolinite with ball milling for 2 h after alkaline leaching at 6 M NaOH for 24 h. Ball milling destroyed the crystal lattice of kaolinite, generating structural defects and dislocations, destabilizing the framework of kaolinite and increasing its reactivity. Furthermore, mechanically activated kaolinite demonstrated a hybrid transformation under alkaline leaching, involving both direct transformation (kaolinite → sodalite) and a two-step transformation (kaolinite → zeolite A → sodalite), depending on the dehydroxylation degree. The complete dehydroxylation of kaolinite induced a two-step transformation under alkaline leaching, as the thermally activated kaolinite did. Kaolinite was directly transformed into sodalite under alkaline conditions (≥ 4 M NaOH), exhibiting heterogeneous nucleation on the surface of kaolinite. Interestingly, the conversion of zeolite A into sodalite required a higher alkaline concentration for the thermal activation of kaolinite under atmospheric pressure, reflecting the advantages of mechanical activation. Mechanical activation can reduce the alkaline concentration required for the preparation of sodalite from kaolinite despite the conversion route, indicating that the preparation of sodalite can be completed under mild conditions.

{"title":"Mechanical activation of kaolinite for sodalite synthesis under mild conditions","authors":"Yi Liu, Baifa Zhang, Mohammad Fahimizadeh, Ting Yu, Zhou Ou, Zhineng Peng, Peng Yuan","doi":"10.1016/j.clay.2025.107796","DOIUrl":"10.1016/j.clay.2025.107796","url":null,"abstract":"<div><div>This study investigated the effects of mechanical activation on the transformation of kaolinite to sodalite under mild conditions. The sodalite prepared via alkaline leaching of kaolinite under different milling times, alkaline concentrations, and leaching times was studied. The prepared zeolites were physically, chemically, and morphologically characterized. The results show that ball milling can significantly reduce the particle size and increase the specific surface area of kaolinite. Highly crystalline sodalite (Na<sub>8</sub>Al<sub>6</sub>Si<sub>6</sub>O<sub>24</sub>(OH)<sub>2</sub>) can be prepared from kaolinite with ball milling for 2 h after alkaline leaching at 6 M NaOH for 24 h. Ball milling destroyed the crystal lattice of kaolinite, generating structural defects and dislocations, destabilizing the framework of kaolinite and increasing its reactivity. Furthermore, mechanically activated kaolinite demonstrated a hybrid transformation under alkaline leaching, involving both direct transformation (kaolinite → sodalite) and a two-step transformation (kaolinite → zeolite A → sodalite), depending on the dehydroxylation degree. The complete dehydroxylation of kaolinite induced a two-step transformation under alkaline leaching, as the thermally activated kaolinite did. Kaolinite was directly transformed into sodalite under alkaline conditions (≥ 4 M NaOH), exhibiting heterogeneous nucleation on the surface of kaolinite. Interestingly, the conversion of zeolite A into sodalite required a higher alkaline concentration for the thermal activation of kaolinite under atmospheric pressure, reflecting the advantages of mechanical activation. Mechanical activation can reduce the alkaline concentration required for the preparation of sodalite from kaolinite despite the conversion route, indicating that the preparation of sodalite can be completed under mild conditions.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107796"},"PeriodicalIF":5.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143714632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modulation of the pyrolysis of ZIF-67 by kaolinite for highly efficient peroxymonosulfate activation

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-26 DOI: 10.1016/j.clay.2025.107798

Yan Mo , Weiwei Yin , Chenhui Long , Chao Gao , Qihang Zhao

The persistent challenge of organic pollutant remediation drives the development of sulfate radical-based advanced oxidation processes, where heterogeneous cobalt-based catalysts face critical stability limitations. To address this, we rationally designed kaolinite-supported carbon-coated cobalt composites through calcination of ZIF-67/Kaol precursors, achieving enhanced peroxymonosulfate (PMS) activation for atrazine degradation. The engineered catalyst combines lamellar structure and active surface groups of kaolinite with ZIF-67-derived nitrogen-doped carbon frameworks, exhibiting exceptional catalytic performance. Mechanistic studies reveal singlet oxygen as the exclusive reactive species, with nitrogen doping in the carbon matrix substantially enhancing charge density and electron transfer efficiency. The carbon coating facilitates electron redistribution while protecting active cobalt sites, enabling sustained catalytic cycles. This work establishes a materials design paradigm combining mineral support engineering with metal-organic framework derivation strategies, demonstrating significant potential for developing robust PMS activation systems in water remediation applications.

{"title":"Modulation of the pyrolysis of ZIF-67 by kaolinite for highly efficient peroxymonosulfate activation","authors":"Yan Mo , Weiwei Yin , Chenhui Long , Chao Gao , Qihang Zhao","doi":"10.1016/j.clay.2025.107798","DOIUrl":"10.1016/j.clay.2025.107798","url":null,"abstract":"<div><div>The persistent challenge of organic pollutant remediation drives the development of sulfate radical-based advanced oxidation processes, where heterogeneous cobalt-based catalysts face critical stability limitations. To address this, we rationally designed kaolinite-supported carbon-coated cobalt composites through calcination of ZIF-67/Kaol precursors, achieving enhanced peroxymonosulfate (PMS) activation for atrazine degradation. The engineered catalyst combines lamellar structure and active surface groups of kaolinite with ZIF-67-derived nitrogen-doped carbon frameworks, exhibiting exceptional catalytic performance. Mechanistic studies reveal singlet oxygen as the exclusive reactive species, with nitrogen doping in the carbon matrix substantially enhancing charge density and electron transfer efficiency. The carbon coating facilitates electron redistribution while protecting active cobalt sites, enabling sustained catalytic cycles. This work establishes a materials design paradigm combining mineral support engineering with metal-organic framework derivation strategies, demonstrating significant potential for developing robust PMS activation systems in water remediation applications.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107798"},"PeriodicalIF":5.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Surfactants aided bleaching of raw kaolin and production of delaminated nano clays via sequential milling

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-26 DOI: 10.1016/j.clay.2025.107794

R. Rakesh , T.M. Ragi , Angitha Francy , A. Peer Mohamed , S. Ananthakumar

Industrial surfactants possessing specific functional groups are better known for obtaining stable clay dispersions. However, the effect of surfactants on the bleaching of kaolin clays during mechanical milling has not yet been studied. In this work, surfactants-assisted bleaching of kaolin clays was investigated through sequential milling (up to 3 stages) to develop an acid-free, water-based green-bleaching process. The aim of this work was to screen the surfactants that offer insitu bleaching thereby improving the brightness without any reductive bleaching using sodium dithionate, and directly produce size-controlled nano-clay particles. Kaolin clays of Indian origin were subjected to mechano-chemical bleaching via planetary milling in the presence of cationic, anionic, and polymeric surfactants in aqueous medium at neutral pH and 300 rpm for 10 min duration. The bleaching efficiency was monitored carefully by noting the color index properties. The end-products were also analyzed for the powder XRD, XRF, Near IR, color coordinates and morphology. The results confirmed that the three-stage mechanical-milling is effective in bleaching of kaolin clays when surfactants like Sodium Dodecyl Sulfate (SDS), commercially known as Sodium Lauryl Sulfate (SLS), is employed. The L* value of kaolin clay is enhanced from 83 to 90 and the b* value decreased from 12.47 to 1.98 in these surfactants. The SEM and TEM analyzes revealed that the mechano-chemical milling was also favoring the delamination of the kaolin clay booklets to produce nano-kaolin. Hence the technique is two-in-one to successfully produce optically bright, highly dispersible, IR reflective, kaolin nano-platelets through green-strategy.

{"title":"Surfactants aided bleaching of raw kaolin and production of delaminated nano clays via sequential milling","authors":"R. Rakesh , T.M. Ragi , Angitha Francy , A. Peer Mohamed , S. Ananthakumar","doi":"10.1016/j.clay.2025.107794","DOIUrl":"10.1016/j.clay.2025.107794","url":null,"abstract":"<div><div>Industrial surfactants possessing specific functional groups are better known for obtaining stable clay dispersions. However, the effect of surfactants on the bleaching of kaolin clays during mechanical milling has not yet been studied. In this work, surfactants-assisted bleaching of kaolin clays was investigated through sequential milling (up to 3 stages) to develop an acid-free, water-based green-bleaching process. The aim of this work was to screen the surfactants that offer insitu bleaching thereby improving the brightness without any reductive bleaching using sodium dithionate, and directly produce size-controlled nano-clay particles. Kaolin clays of Indian origin were subjected to mechano-chemical bleaching via planetary milling in the presence of cationic, anionic, and polymeric surfactants in aqueous medium at neutral pH and 300 rpm for 10 min duration. The bleaching efficiency was monitored carefully by noting the color index properties. The end-products were also analyzed for the powder XRD, XRF, Near IR, color coordinates and morphology. The results confirmed that the three-stage mechanical-milling is effective in bleaching of kaolin clays when surfactants like Sodium Dodecyl Sulfate (SDS), commercially known as Sodium Lauryl Sulfate (SLS), is employed. The L* value of kaolin clay is enhanced from 83 to 90 and the b* value decreased from 12.47 to 1.98 in these surfactants. The SEM and TEM analyzes revealed that the mechano-chemical milling was also favoring the delamination of the kaolin clay booklets to produce nano-kaolin. Hence the technique is two-in-one to successfully produce optically bright, highly dispersible, IR reflective, kaolin nano-platelets through green-strategy.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107794"},"PeriodicalIF":5.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accelerating of Fe3+/Fe2+ redox cycle using palygorskite as phase regulator for peroxymonosulfate oxidation

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-26 DOI: 10.1016/j.clay.2025.107790

Yunhui Tian, Shilin Li, Guangxin Zhang

This study presents the synthesis of a Fe-based catalyst via a one-pot calcination method, emphasizing the role of palygorskite (Pal) in modifying the catalyst's phase composition. The incorporation of palygorskite led to a robust interaction with FeOCl and FeCl₂, resulting in a porous structure enriched with active sites. The prepared catalyst had high surface area (69.1 m²/g) and pore volume (0.167 cm³/g) with interwoven rod-like structure. These characteristics were essential for enhancing the activation of peroxymonosulfate (PMS). Textile wastewater is one of the main sources of industrial wastewater in China, and RhB is one of the commonly used dyes in textile industry. The performance of the synthesized Fe/Pal catalyst was evaluated in the context of degrading Rhodamine B (RhB). The catalyst exhibited remarkable efficacy attributed to the dynamic Fe³⁺/Fe²⁺ redox cycle. Under optimized conditions, 0.1 g/L activated catalyst can remove 85 % RhB within 10 min. Quenching experiments further elucidated the mechanisms involved in pollutant removal, revealing that sulfate radicals and singlet oxygen were the predominant reactive species. Overall, the findings underscored the potential of iron/mineral matrix composite catalysts in the effective treatment of organic pollutants. This research not only advances the understanding of catalyst design but also offers promising pathways for the broader application of these materials in environmental remediation efforts.

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引用次数: 0

Paraffin@Hectorite-SiO2/Fe3O4 microcapsule phase change fluid for efficient photothermal energy storage and heat dissipation

IF 5.3 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2025-03-23 DOI: 10.1016/j.clay.2025.107797

Huanyu Zhu , Minghui Li , Hao Yi , Feifei Jia , Jinyue Xu , Shaoxian Song

Suspension stability and thermal conductivity are crucial for enhancing the heat dissipation efficiency of latent heat fluid. In this work, Paraffin@Hectorite-SiO₂/Fe₃O₄ phase change microcapsule based on paraffin core and hectorite/SiO₂/Fe₃O₄ composite shell was designed and fabricated using Pickering method, and it was dispersed into water to obtain latent heat fluid. DSC analysis indicated that the latent heat storage capacity of MPCM was 170.44 J/g with the 69.34 % encapsulation ratio. TGA analysis demonstrated that composite shell structure improved the thermal stability of paraffin. Heat dissipation tests indicated that the heat dissipation efficiency of Paraffin@Hectorite-SiO₂/Fe₃O₄-Water LHF were improved by 22.9 % compared with pure water, and the fluid could keep suspended at least 30 days. The introduction of Fe₃O₄ on shell structure enhanced the light absorption rate and the surface temperature could raise to 55.1 °C after exposure to sunlight for 15 min. The resultant LHF has a promising potential for applications in heat dissipation and solar energy storage.

{"title":"Paraffin@Hectorite-SiO2/Fe3O4 microcapsule phase change fluid for efficient photothermal energy storage and heat dissipation","authors":"Huanyu Zhu , Minghui Li , Hao Yi , Feifei Jia , Jinyue Xu , Shaoxian Song","doi":"10.1016/j.clay.2025.107797","DOIUrl":"10.1016/j.clay.2025.107797","url":null,"abstract":"<div><div>Suspension stability and thermal conductivity are crucial for enhancing the heat dissipation efficiency of latent heat fluid. In this work, Paraffin@Hectorite-SiO<sub>2</sub>/Fe<sub>3</sub>O<sub>4</sub> phase change microcapsule based on paraffin core and hectorite/SiO<sub>2</sub>/Fe<sub>3</sub>O<sub>4</sub> composite shell was designed and fabricated using Pickering method, and it was dispersed into water to obtain latent heat fluid. DSC analysis indicated that the latent heat storage capacity of MPCM was 170.44 J/g with the 69.34 % encapsulation ratio. TGA analysis demonstrated that composite shell structure improved the thermal stability of paraffin. Heat dissipation tests indicated that the heat dissipation efficiency of Paraffin@Hectorite-SiO<sub>2</sub>/Fe<sub>3</sub>O<sub>4</sub>-Water LHF were improved by 22.9 % compared with pure water, and the fluid could keep suspended at least 30 days. The introduction of Fe<sub>3</sub>O<sub>4</sub> on shell structure enhanced the light absorption rate and the surface temperature could raise to 55.1 °C after exposure to sunlight for 15 min. The resultant LHF has a promising potential for applications in heat dissipation and solar energy storage.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"271 ","pages":"Article 107797"},"PeriodicalIF":5.3,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143682815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0