Investigation of Structure and Composition of Clay in Lakes of Latgale for Practical Use

Abstract

<jats:p>Sedimentary clay of three Latvia region of Latgale lakes – Zeiļi, Pauguļi and Plusons – was investigated. Mineral composition was determined by X-ray diffraction, the average size and size distribution of particles by dynamic light scattering method, specific surface by Brunauer-Emmett-Teller method, and adsorption characteristics after methylene blue: adsorption capacity and adsorption isotherms. The samples contained typical clay crystalline phases – illite, kaolinite – and rock forming minerals – quartz, dolomite, calcite, plagioclase, albite, and enstatite. The granulometric content of samples is mostly characterised by silt (2 – 63 µm) and clay (&lt; 2 µm) fractions. Specific surface area varied from 9.45 to 20.68 m2/g. The adsorption capacity of lake clay was in the range of 25.8 – 45.8 mg/g. Clay adsorption isotherms were represented by the second and fifth type curves according to the International Union of Pure and Applied Chemistry (IUPAC) classification, indicating the presence of micro- and macroporous space in samples and strong intermolecular interactions. The difference between properties of clay in different lakes and at different depths and their influencing factors have been clarified. The information obtained enables to predict the areas of use of clay in cosmetics and medical treatment.</jats:p>

Lake Zeiļu Clay Application Induced Changes in Human Skin Hydration, Elasticity, Transepidermal Water Loss and PH in Healthy Individuals

“…Clay can be used as antiseptic and disinfectant, dermatological protector and solar protector [18,21]. The granulometric content of lake clay is mostly characterized by silt (2-63 µm) and clay (<2 µm) fractions [22]. The average particle size of the clay (26.3 µm) that is formed by kaolinite, illite and a swelling clay can induce the microcirculation of the skin.…”

“…Lake clay contained crystalline phases-illite and kaolinite [22]. Significant qualities of kaolinites are their opacity, softness and non-abrasiveness [25].…”

“…Adsorption capacity of Lake Zeil , u clay varies from 45.8 mg/g. Considering its mineralogical and granulometric content, specific surface area and adsorption capacity, Lake Zeil , u clay is suitable for use in cosmetics and medical treatment [22].…”

The Application Perspectives of Lake Clay Infused With Natural Active Agents - Essential Oils in Cosmetology and Dermatology

“…Lake clay effect can be different from lithospheric clay considering that lake clay has formed in different environment and is covered by sapropel layer which medical effectivity has been proven. Considering lake clay chemical parameters, granulometric content, specific surface area and adsorption capacity, lake clay is suitable for cosmetic and dermatological application [12], [13]. However, the presence of some microorganisms in the clay presents the risk of infection, spoilage of the product during storage.…”