{"title":"A Study of the Process Kinetics of Acidic Decomposition of Eudialyte","authors":"D. V. Maiorov, M. V. Maslova","doi":"10.1134/S0040579524700234","DOIUrl":null,"url":null,"abstract":"<p><b>Abstract</b>—The raw-material base and the manufacture of zirconium, niobium, and rare-earth products in Russia are briefly reviewed. The prospects for their manufacture on the basis of the integrated processing of eudialyte are shown. The main methods of the acidic processing of this mineral are considered. The results of studying the kinetics of decomposition of eudialyte with hydrochloric and sulfuric acids are given. It is established that the process of acidic decomposition of eudialyte can be described with a high degree of accuracy by the formal equation <i>d</i>(1 – α)/<i>d</i>τ = –<i>k</i>(1 – α)<sup>2</sup> for the conversion rate, from which the activation energies of the processes are determined (79.69 and 48.90 kJ/mol for HCl and H<sub>2</sub>SO<sub>4</sub>, respectively). Based on the topochemical kinetic equations describing various types, mechanisms, and geometric models of solid-phase reactions, the experimental data are mathematically processed. It is established that the mechanism of acidic decomposition of eudialyte is most accurately described by the equation (1 – 2α/3 – 1 –α)<sup>2/3</sup> = <i>k</i><sub>GB</sub>τ) for the Ginstling–Brounschtein diffusion-controlled process.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 1","pages":"122 - 131"},"PeriodicalIF":0.7000,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Theoretical Foundations of Chemical Engineering","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1134/S0040579524700234","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0
Abstract—The raw-material base and the manufacture of zirconium, niobium, and rare-earth products in Russia are briefly reviewed. The prospects for their manufacture on the basis of the integrated processing of eudialyte are shown. The main methods of the acidic processing of this mineral are considered. The results of studying the kinetics of decomposition of eudialyte with hydrochloric and sulfuric acids are given. It is established that the process of acidic decomposition of eudialyte can be described with a high degree of accuracy by the formal equation d(1 – α)/dτ = –k(1 – α)2 for the conversion rate, from which the activation energies of the processes are determined (79.69 and 48.90 kJ/mol for HCl and H2SO4, respectively). Based on the topochemical kinetic equations describing various types, mechanisms, and geometric models of solid-phase reactions, the experimental data are mathematically processed. It is established that the mechanism of acidic decomposition of eudialyte is most accurately described by the equation (1 – 2α/3 – 1 –α)2/3 = kGBτ) for the Ginstling–Brounschtein diffusion-controlled process.
期刊介绍:
Theoretical Foundations of Chemical Engineering is a comprehensive journal covering all aspects of theoretical and applied research in chemical engineering, including transport phenomena; surface phenomena; processes of mixture separation; theory and methods of chemical reactor design; combined processes and multifunctional reactors; hydromechanic, thermal, diffusion, and chemical processes and apparatus, membrane processes and reactors; biotechnology; dispersed systems; nanotechnologies; process intensification; information modeling and analysis; energy- and resource-saving processes; environmentally clean processes and technologies.