Urgench State University (Urgench, Republic of Uzbekistan)

Matchonov Sh. K., Associate Professor, Candidate of Engineering Sciences, mbsh76@mail.ru
Ruzmetova A. Sh., Associate Professor, PhD in Engineering Sciences
Yakubov Yu. Kh., Trainee Teacher
Kurbanov D. Sh., Senior Lecturer, PhD Student

This article identifies promising kaolin deposits in the territory of the Republic of Uzbekistan. It describes studies of the characteristics of kaolin ore of the Khodzhakul deposit, its reserves, physical and chemical properties, as well as methods for obtaining valuable products from this ore, such as metakaolin and technical alumina, in compliance with relevant standards. The results of X-ray, IR spectrographic, and differential thermal analyzes are presented; usability of Khodzhakul kaolin for obtaining the specified products is theoretically and practically studied. The experimental part of the work uses traditional qualitative and quantitative chemical analysis methods, instrumental mineral composition analysis methods, and kaolin rock sample processing experiments. The test samples were selected and prepared in compliance with the applicable standards and technical specifications for the specific products. The effects of the kaolin calcination temperatures on the production process and metakaolin properties were studied. The pozzolanic activity of metakaolin samples was established by the amount of CaO absorbed from the lime solution over 60 days. The paper describes a process flow for obtaining metakaolin by heat treatment, including the stages of kaolin drying, grinding, and roasting. A technology has been developed for isolating kaolin from the quartz-kaolin rock of the Khodzhakul deposit and for producing technical alumina by acid treatment. Three types of acids were used in the experiments: sulfuric, hydrochloric, and nitric acids. The paper proposes a process flow for obtaining technical alumina by acid treatment of metakaolin generated from the Khodzhakul kaolin. The resulting products are in great demand in many industrial sectors of Uzbekistan. This indicates the importance and relevance of the research conducted and process flows presented.

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