Clay Minerals最新文献_第5页

Simple and efficient: performance of palladium-loaded sepiolite for electrocatalytic ethanol oxidation 简单高效:载钯海泡石电催化乙醇氧化性能研究

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2022.40

Jun‐Ling Zhao, Liang Li, Liuqiang Li, Siru Zhang, Shiqi Chen, Zheng Yuan, Ling Wang

{"title":"Simple and efficient: performance of palladium-loaded sepiolite for electrocatalytic ethanol oxidation","authors":"Jun‐Ling Zhao, Liang Li, Liuqiang Li, Siru Zhang, Shiqi Chen, Zheng Yuan, Ling Wang","doi":"10.1180/clm.2022.40","DOIUrl":"https://doi.org/10.1180/clm.2022.40","url":null,"abstract":"Abstract High-performance electrodes with outstanding catalysts play a vital role in the commercial application of direct ethanol fuel cells. In the present study, a supported catalyst with controllable Pd loading, prepared using a facile impregnation method with sepiolite as a carrier, was synthesized and tested for electrocatalytic oxidation of ethanol. Physical characterization revealed the pore structure and large specific surface area of the sepiolite, which provided excellent conditions for the loading of nanometal clusters. The Pd-sepiolite had greater electrocatalytic ethanol activity and anti-intermediate product poisoning performance than a metallic Pd disc electrode under alkaline conditions. Under these experimental conditions, the electrochemical activity in terms of ethanol oxidation increased significantly with increasing Pd loading. Considering both the activity and stability of the electrodes, 23 wt.% Pd loading on sepiolite was selected with a coating amount of 140 μg cm–2 on glassy carbon. Factors such as ethanol/potassium hydroxide concentration, scanning rate and temperature had direct impacts on peak current densities as well as on reaction kinetics as depicted by Tafel plots. The electrochemical impedance test showed that Pd intercalation could improve significantly the conductivity of sepiolite and reduce the electron-transfer resistance in the electrocatalytic process. Thus, Pd-loaded sepiolite is a simple and effective catalyst for direct ethanol fuel cells.","PeriodicalId":10311,"journal":{"name":"Clay Minerals","volume":"57 1","pages":"211 - 222"},"PeriodicalIF":1.5,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47793386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Adsorption of lead by kaolinite, montmorillonite, goethite and ferrihydrite: performance and mechanisms based on quantitative analysis 高岭石、蒙脱石、针铁矿和水合铁对铅的吸附:基于定量分析的性能和机理

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2022.41

Xiaopan Mao, Haibo Liu, Z. Chu, Tianhu Chen, Xuehua Zou, Dong Chen, Xuemei Zhang, Jinchao Hu

{"title":"Adsorption of lead by kaolinite, montmorillonite, goethite and ferrihydrite: performance and mechanisms based on quantitative analysis","authors":"Xiaopan Mao, Haibo Liu, Z. Chu, Tianhu Chen, Xuehua Zou, Dong Chen, Xuemei Zhang, Jinchao Hu","doi":"10.1180/clm.2022.41","DOIUrl":"https://doi.org/10.1180/clm.2022.41","url":null,"abstract":"Abstract This work elucidated the performance and mechanisms of Pb2+ adsorption by kaolinite, montmorillonite, goethite and ferrihydrite using batch experiments. The contributions of various adsorption mechanisms were quantified using a stepwise extraction method. Several characterizations (scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, point of zero charge analysis and X-ray fluorescence) were utilized to analyse the physicochemical properties and the potential adsorption mechanisms. The results indicated that the adsorption processes of montmorillonite and goethite approached equilibrium within 20 min, while 60 min were required for the adsorption processes of kaolinite and ferrihydrite. The adsorption processes of Pb2+ by the four minerals best fit the pseudo-second order model. The adsorption capacities of the four minerals for Pb2+ followed the order: montmorillonite > goethite > ferrihydrite > kaolinite, and the maximum adsorption capacities were 69.20, 46.95, 34.32 and 18.62 mg g–1, respectively. The stepwise extraction test showed that the adsorption mechanism of Pb2+ was dominated by ion exchange for montmorillonite, precipitation and complexation for goethite and complexation for kaolinite and ferrihydrite.","PeriodicalId":10311,"journal":{"name":"Clay Minerals","volume":"57 1","pages":"230 - 240"},"PeriodicalIF":1.5,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42519400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 4

Molecular simulation of the adsorption of the hydration inhibitor N1,N1’-(ethane-1,2-diethyl)bis(N1-(2-aminoethyl)ethane-1,2-diamine onto montmorillonite 水化抑制剂N1,N1′-(乙烷-1,2-二乙基)双(N1-(2-氨基乙基)乙烷-1,2-二胺在蒙脱土上吸附的分子模拟

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2022.37

Shi Yuan, Xin Zhao, Rong-chao Cheng, Yuanzhi Qu, Jiawen Xue, Yiang Li, Jinsheng Sun, Jiafang Xu

{"title":"Molecular simulation of the adsorption of the hydration inhibitor N1,N1’-(ethane-1,2-diethyl)bis(N1-(2-aminoethyl)ethane-1,2-diamine onto montmorillonite","authors":"Shi Yuan, Xin Zhao, Rong-chao Cheng, Yuanzhi Qu, Jiawen Xue, Yiang Li, Jinsheng Sun, Jiafang Xu","doi":"10.1180/clm.2022.37","DOIUrl":"https://doi.org/10.1180/clm.2022.37","url":null,"abstract":"Abstract Clay-swelling inhibitors are often used to prevent the hydration of clay minerals, which can reduce the risk of wellbore instability and reservoir damage. The molecular behaviour of clay-swelling inhibitors at the montmorillonite–water interface is crucial for revealing their inhibition mechanisms and for evaluating and designing inhibitor molecules. N1,N1'-(ethane-1,2-diyl)bis(N1-(2-aminoethyl)ethane-1,2-diamine) (NETS), a low-molecular-weight clay-swelling inhibitor, is used widely to prevent clay swelling. Herein, the adsorption mechanism of NETS on the surface of montmorillonite (Mnt) was investigated using molecular dynamics (MD) simulations. In particular, the effects of molecular conformation and temperature on adsorption ability were investigated. The results show that the adsorption ability of NETS on the Mnt surface was affected significantly by the molecular conformation. Specifically, the dihedral angle of NETS adsorbed on the surface of Mnt decreases by ~20° and tends to adsorb on the surface of Mnt in a plane state. In addition, the adsorption stability of NETS on the Mnt surface decreased with increasing temperature, as was found using MD simulations. Detailed analysis shows that increasing temperature can lead to more frequent conformational changes, which weaken the interaction between NETS and Mnt, thus reducing adsorption stability. These molecular insights into the interaction mechanism between NETS and Mnt are beneficial for the evaluation of inhibitory effects and for the selection and molecular design of new clay-swelling inhibitors for use in drilling fluids.","PeriodicalId":10311,"journal":{"name":"Clay Minerals","volume":"57 1","pages":"192 - 201"},"PeriodicalIF":1.5,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44004534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Geometry optimization of an electrochemical reactor for bleaching kaolin 高岭土漂白电化学反应器的几何优化

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2022.36

J. A. Cobos-Murcia, E. Hernández-Aguilar, A. Trujillo-Estrada, Grisell Gallegos-Ortega, V. Reyes-Cruz

{"title":"Geometry optimization of an electrochemical reactor for bleaching kaolin","authors":"J. A. Cobos-Murcia, E. Hernández-Aguilar, A. Trujillo-Estrada, Grisell Gallegos-Ortega, V. Reyes-Cruz","doi":"10.1180/clm.2022.36","DOIUrl":"https://doi.org/10.1180/clm.2022.36","url":null,"abstract":"Abstract High-whiteness kaolinite mining reserves are scarce. In some locations, it is necessary to remove material to access them (adding to the cost). Therefore, processes have been developed to eliminate contaminants, such as iron, and provide alternatives to the used contaminated materials that, after being treated, meet quality criteria. In our previous research, we developed an electrochemical process for kaolin whitening at the laboratory level and bench scale, demonstrating the reaction mechanisms that occur during the removal of iron from kaolin. However, the geometry used at the laboratory level does not present the most suitable position for the electrodes. Therefore, in the present study, we focused on the geometry and the function of the electrodes. This is necessary during the escalation process to reach the pilot-scale level. The study was carried out using computer-aided engineering in the COMSOL Multiphysics computer program and by analysing the distribution of the electric potential and the electric current of the geometries considered while performing the scaling. The results indicated that the change in the anode position from perpendicular to parallel to the discs improved the distribution of electric current density on the cathode surface and so increased the elimination of iron through electrochemical deposition. Similarly, to reduce the amount of material used in the construction of the reactor, the anode-size effect was analysed, revealing that relatively small anodes improved the distribution of electric current density over the entire surface of the electrode and not only at the edges.","PeriodicalId":10311,"journal":{"name":"Clay Minerals","volume":"57 1","pages":"183 - 191"},"PeriodicalIF":1.5,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45478044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Formulation and release kinetics of ibuprofen–bentonite tablets 布洛芬-膨润土片的配方及释放动力学

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2022.35

Jamal Alyoussef Alkrad, Sind Al-Sammarraie, E. Dahmash, N. Qinna, A. Naser

{"title":"Formulation and release kinetics of ibuprofen–bentonite tablets","authors":"Jamal Alyoussef Alkrad, Sind Al-Sammarraie, E. Dahmash, N. Qinna, A. Naser","doi":"10.1180/clm.2022.35","DOIUrl":"https://doi.org/10.1180/clm.2022.35","url":null,"abstract":"Abstract Bentonite-based tablets offer multiple advantages over other types of formulated tablets, including being biocompatible and cost-effective, and they can be used to develop gel-like matrices that have potential for use in sustained-release formulations. Developing a high-load sustained-release formulation has been reported to be challenging; therefore, the aim of this study was to develop systematically bentonite-based sustained-release tablets for a high-load active agent (ibuprofen) and investigate their release kinetics. Ibuprofen-loaded tablets (800 mg) were prepared using wet and dry granulation followed by enteric coating of the tablets. Fourier-transform infrared spectroscopy, differential scanning calorimetry and X-ray powder diffraction were used to evaluate the compatibility of ibuprofen with bentonite. The results show that these tablets comply with compendial requirements. In addition, the release profile of the formulations reveals that the drug follows a non-Fickian release model. The present formulation demonstrates a new use of bentonite as a safe and cost-effective excipient with adequate binding and compaction for preparing sustained-release tablets.","PeriodicalId":10311,"journal":{"name":"Clay Minerals","volume":"57 1","pages":"172 - 182"},"PeriodicalIF":1.5,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46128376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 1

2022 list of referees for Clay Minerals 2022年粘土矿物评审名单

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2023.5

引用次数: 0

Nitrate adsorption characteristics of synthesized allophanes with various chemical compositions 不同化学成分合成的allophanes对硝酸盐的吸附特性

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2022.39

F. Ohashi

引用次数: 0

CLM volume 57 issue 3-4 Cover and Front matter CLM第57卷第3-4期封面和封面

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-09-01 DOI: 10.1180/clm.2023.8

引用次数: 0

Influence of zirconia on the sintering behaviour and mechanical properties of reaction-sintered mullite-based composite ceramics 氧化锆对反应烧结莫来石基复合陶瓷烧结行为和力学性能的影响

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-06-01 DOI: 10.1180/clm.2022.25

Zhenying Liu, N. Xie, Shouwu Huang, Hanxin Zhang, Chongmei Wu, Kai Cui, Yin Liu, Hongzheng Zhu, Jinbo Zhu, Changguo Xue

{"title":"Influence of zirconia on the sintering behaviour and mechanical properties of reaction-sintered mullite-based composite ceramics","authors":"Zhenying Liu, N. Xie, Shouwu Huang, Hanxin Zhang, Chongmei Wu, Kai Cui, Yin Liu, Hongzheng Zhu, Jinbo Zhu, Changguo Xue","doi":"10.1180/clm.2022.25","DOIUrl":"https://doi.org/10.1180/clm.2022.25","url":null,"abstract":"ABSTRACT High-performance mullite-based composite ceramics were prepared successfully using natural kaolin and alumina as raw materials and ZrO2 as an additive. The influence of sintering temperature and ZrO2 content on the sintering behaviour and mechanical properties of zirconia-toughened mullite ceramics was studied systematically. With increasing sintering temperature from 1450°C to 1560°C, the primary phases of as-sintered composite ceramics were mullite and corundum with a small amount of ZrO2, and the bulk density of the composite ceramics increased from 2.29 to 2.72 g cm–3. Furthermore, the ZrO2 phase transition promoted transgranular fracture, and ZrO2 grains were pinned at the grain boundaries, thereby enhancing the mechanical strength of the composite ceramics. Moreover, the AZS12 sample, with 12 wt.% ZrO2 and sintered at 1560°C, had the greatest flexural strength and fracture toughness of 91.6 MPa and 2.47 MPa m–1/2, respectively. Adding ZrO2 to the composite ceramics increased their flexural strength by ~37.6%.","PeriodicalId":10311,"journal":{"name":"Clay Minerals","volume":"57 1","pages":"97 - 104"},"PeriodicalIF":1.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43920951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 1

The beneficiation of the Pütürge pyrophyllite ore by flotation: mineralogical and chemical evaluation Pütürge叶蜡石浮选选矿的矿物学和化学评价

IF 1.5 4区地球科学

Clay Minerals Pub Date : 2022-06-01 DOI: 10.1180/clm.2022.24

Suna Elif Akçin, G. Bulut, Bala Ekinci Şans, F. Esenli

{"title":"The beneficiation of the Pütürge pyrophyllite ore by flotation: mineralogical and chemical evaluation","authors":"Suna Elif Akçin, G. Bulut, Bala Ekinci Şans, F. Esenli","doi":"10.1180/clm.2022.24","DOIUrl":"https://doi.org/10.1180/clm.2022.24","url":null,"abstract":"Abstract Samples from the pyrophyllite reserves in the Malatya–Pütürge region, used in the production of the whitest cement in Europe, were beneficiated using flotation. The mineralogical composition of the natural pyrophyllite, as determined using X-ray diffraction, includes pyrophyllite, kaolinite, quartz, illite–mica and feldspar. The chemical composition of pyrophyllite contains 69.75% SiO2 and 23.04% Al2O3. The pyrophyllite percentage (40–45 wt.%) of the natural sample increased to 60–80 wt.% after flotation. In flotation experiments, the effects of reagent amounts, types and their mixtures were investigated. Methyl isobutyl carbinol (MIBC) and pine oil as frothers and kerosene as a collector were used in the flotation studies. The use of reagents as mixtures has a positive effect on the beneficiation compared to use on their own. The best result was obtained for a mixture of MIBC with kerosene, which is a non-ionic hydrocarbon oil, yielding a concentrate containing 26.63% Al2O3. Improved results were also observed for kerosene plus frother mixtures after flotation cleaning circuits. The bubbles formed during flotation were photographed and the bubble diameters were measured using the ImageJ program. The Al2O3 content was evaluated by correlating the bubble diameters. In general, selectivity decreased during experiments in which bubble diameters were reduced.","PeriodicalId":10311,"journal":{"name":"Clay Minerals","volume":"57 1","pages":"87 - 96"},"PeriodicalIF":1.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49325151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 1