{"title":"Investigation of halloysite thermal decomposition through differential thermal analysis (DTA): Mechanism and kinetics assessment","authors":"","doi":"10.1016/j.jics.2024.101413","DOIUrl":null,"url":null,"abstract":"<div><div>The study focused on analysing the kinetics of halloysite decomposition using the differential thermal analysis (DTA) technique. Tests were carried out across a temperature span from ambient temperature to 1673 K, employing heating rates spanning from 5 to 20 °C.min<sup>−1</sup>. X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR) were utilized to identify the phases formed at different temperatures. Activation energies for halloysite decomposition were determined through isothermal and non-isothermal treatments, yielding values of approximately 151.68 kJ mol<sup>−1</sup> and 173.14 kJ mol<sup>−1</sup>, respectively. The Ligero method's Avrami constant parameter (<span><math><mrow><mi>n</mi></mrow></math></span>) and the Matusita method's numerical factor parameter (<span><math><mrow><mi>m</mi></mrow></math></span>), linked to crystal growth dimensions, were both around 1.5. These findings indicate that the degradation of halloysite is primarily governed by bulk nucleation, succeeded by the 3-dimensional growth of <em>meta</em>-halloysite characterized by polyhedron-like structure, regulated by diffusion from a consistent number of nuclei. The frequency factor for halloysite dehydroxylation was established at 8.48 × 10⁸ s⁻<sup>1</sup>.</div></div>","PeriodicalId":17276,"journal":{"name":"Journal of the Indian Chemical Society","volume":null,"pages":null},"PeriodicalIF":3.2000,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the Indian Chemical Society","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0019452224002930","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
The study focused on analysing the kinetics of halloysite decomposition using the differential thermal analysis (DTA) technique. Tests were carried out across a temperature span from ambient temperature to 1673 K, employing heating rates spanning from 5 to 20 °C.min−1. X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR) were utilized to identify the phases formed at different temperatures. Activation energies for halloysite decomposition were determined through isothermal and non-isothermal treatments, yielding values of approximately 151.68 kJ mol−1 and 173.14 kJ mol−1, respectively. The Ligero method's Avrami constant parameter () and the Matusita method's numerical factor parameter (), linked to crystal growth dimensions, were both around 1.5. These findings indicate that the degradation of halloysite is primarily governed by bulk nucleation, succeeded by the 3-dimensional growth of meta-halloysite characterized by polyhedron-like structure, regulated by diffusion from a consistent number of nuclei. The frequency factor for halloysite dehydroxylation was established at 8.48 × 10⁸ s⁻1.
期刊介绍:
The Journal of the Indian Chemical Society publishes original, fundamental, theorical, experimental research work of highest quality in all areas of chemistry, biochemistry, medicinal chemistry, electrochemistry, agrochemistry, chemical engineering and technology, food chemistry, environmental chemistry, etc.