Investigation of iron oxide and kaolinite interactions during sintering under controlled atmosphere

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science Pub Date : 2025-07-28 DOI:10.1016/j.clay.2025.107945

Fleur Guillemin , Mathieu Duttine , Gisèle Lecomte-Nana , Youssef El Hafiane , Claire Peyratout , Agnès Smith

{"title":"Investigation of iron oxide and kaolinite interactions during sintering under controlled atmosphere","authors":"Fleur Guillemin , Mathieu Duttine , Gisèle Lecomte-Nana , Youssef El Hafiane , Claire Peyratout , Agnès Smith","doi":"10.1016/j.clay.2025.107945","DOIUrl":null,"url":null,"abstract":"<div><div>This study investigates the impact of atmosphere conditions on the thermal transformations of iron-enriched kaolin. Natural kaolin was chemically enriched with iron at two concentrations. Fine characterisation was conducted using X-ray diffraction, Mössbauer spectroscopy, solid-state nuclear magnetic resonance and electron dispersive spectroscopy. The samples were heat-treated at 1050 °C and 1400 °C under synthetic air and argon to assess the influence of these conditions on their transformations.</div><div>Analyses revealed that presence of iron significantly influenced reaction kinetics. Under oxidizing atmosphere, the formation of mullite was facilitated by an equilibrium with hematite. The presence of iron accelerated the formation of secondary mullite and cristobalite, though the effect was not proportional to iron concentration. Conversely, under oxygen-deficient atmosphere, the reaction pathway diverged, leading to the formation of hercynite, tridymite (and after cristobalite) and mullite. Iron similarly promoted formation of these phases. No significant differences were observed for the pure kaolin sample under either atmosphere.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"276 ","pages":"Article 107945"},"PeriodicalIF":5.8000,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Clay Science","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0169131725002509","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}

引用次数: 0

Abstract

This study investigates the impact of atmosphere conditions on the thermal transformations of iron-enriched kaolin. Natural kaolin was chemically enriched with iron at two concentrations. Fine characterisation was conducted using X-ray diffraction, Mössbauer spectroscopy, solid-state nuclear magnetic resonance and electron dispersive spectroscopy. The samples were heat-treated at 1050 °C and 1400 °C under synthetic air and argon to assess the influence of these conditions on their transformations.

Analyses revealed that presence of iron significantly influenced reaction kinetics. Under oxidizing atmosphere, the formation of mullite was facilitated by an equilibrium with hematite. The presence of iron accelerated the formation of secondary mullite and cristobalite, though the effect was not proportional to iron concentration. Conversely, under oxygen-deficient atmosphere, the reaction pathway diverged, leading to the formation of hercynite, tridymite (and after cristobalite) and mullite. Iron similarly promoted formation of these phases. No significant differences were observed for the pure kaolin sample under either atmosphere.

查看原文本刊更多论文

可控气氛烧结过程中氧化铁与高岭石相互作用的研究

研究了大气条件对富铁高岭土热转化的影响。用两种浓度的铁对天然高岭土进行化学富集。利用x射线衍射、Mössbauer光谱、固体核磁共振和电子色散光谱对其进行了精细表征。在1050°C和1400°C的合成空气和氩气条件下对样品进行热处理，以评估这些条件对其转变的影响。分析表明，铁的存在显著影响反应动力学。在氧化气氛下，与赤铁矿的平衡有利于莫来石的形成。铁的存在加速了次生莫来石和方石英的形成，尽管这种影响与铁的浓度不成正比。反之，在缺氧环境下，反应途径发生分化，形成海方英石、钇石（方英石后）和莫来石。铁同样促进了这些相的形成。纯高岭土样品在两种气氛下均无显著差异。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Applied Clay Science 地学-矿物学

CiteScore

10.30

自引率

10.70%

发文量

289

审稿时长

39 days

期刊介绍： Applied Clay Science aims to be an international journal attracting high quality scientific papers on clays and clay minerals, including research papers, reviews, and technical notes. The journal covers typical subjects of Fundamental and Applied Clay Science such as: • Synthesis and purification • Structural, crystallographic and mineralogical properties of clays and clay minerals • Thermal properties of clays and clay minerals • Physico-chemical properties including i) surface and interface properties; ii) thermodynamic properties; iii) mechanical properties • Interaction with water, with polar and apolar molecules • Colloidal properties and rheology • Adsorption, Intercalation, Ionic exchange • Genesis and deposits of clay minerals • Geology and geochemistry of clays • Modification of clays and clay minerals properties by thermal and physical treatments • Modification by chemical treatments with organic and inorganic molecules(organoclays, pillared clays) • Modification by biological microorganisms. etc...