showing 7 related works from this author
The Suitability of Chemically and Thermally Activated Quaternary Clays of Latvia as Raw Material for Geopolymer Binders
2013
It is now accepted that new binders are needed to replace Portland cement (PC) for enhanced environmental and durability performance. The urge to reduce emissions of carbon and the fact that PC structures having built a few decades ago are already facing disintegration problems points out the handicaps of PC binders. Research works carried out in developing of alkali-activated binders show that this new type of binder could have a huge potential to become as alternative building material. Latvian Quaternary clays were studied from the point of view of the national economy, analysing the physical properties and chemical composition of those sediments in connection with the possibilities of …
Comparison of Structure and Properties of Differently Treated Illite Clay and Products
2014
The investigation is focused on modification of the structure 2:1 sheet silicates - illite clay by subjecting them to chemical and microbiological impact. It is shown that alkaline activation of illite clay by sodium hydroxide leads to the slight structural changes mainly characterized by water link changes. The effect of bacteria Ps. fluorescens AM PS11on structure changes of illite is small and is influenced on rheology of treated clay.It is shown that the influence of chemical treatment on porosity, bulk density and increase of compressive strength of sintered ceramic samples is notable.
Application of differently treated illite and illite clay samples for the development of ceramics
2017
Abstract This study represents the results of investigations on the possible geopolymer formation of an alkali, mechanically and thermally (including hydrothermally) activated 2:1 layer silicate, namely, illite and illite clay, for low-temperature ceramic products. The main starting materials were Quaternary illite clay samples taken from the Apriki–Laza pit in Latvia. For the investigations, an intermediate composition of illite clay and separated illite were used. The following research methods for the treated illite and illite clay were used: the phase transition was analysed by differential thermal analysis, while the phase compositions, microstructures and structures were analysed by X…
Suitability of Illite Based Clays of Latvia for Chemical and Thermal Activation
2014
Materials has been synthesized in the temperature range from 600-800 0C from illite based clays of Latvia under activation of KOH and NaOH solutions (4-6 M). Compressive strength and apparent porosity were measured. The effect of the concentration of KOH and NaOH solutions on the material mechanical properties was investigated by means of infrared spectroscopy (IR). Compressive strength data of the materials showed that via such activation building materials with good quality can be obtained.
Mechanical properties of materials obtained via alkaline activation of illite-based clays of Latvia
2015
Materials has been synthesized in the temperature range from 60-100 °C from two illite based clays of Latvia under activation of KOH and NaOH solutions (4-6 M). Compressive strength and apparent porosity were measured. The effect of concentration of KOH and NaOH solutions on the material mechanical properties was investigated by means of infrared spectroscopy (IR). Compressive strength data of the materials showed that via such activation could obtain building materials with good quality.
Influence of Bacteria <i>Pseudomonas fluorescens</i> on the Properties of Latvian Clay
2014
Wide varieties of bacteria are able to produce extracellular polymeric substances (EPS) which are mostly composed of polysaccharides. It is suggested that EPS substances can alter certain clay soil properties due to their ability to adhere to the surface of mineral particles. Most common used microorganisms by the researchers for this purpose are of either genus Bacillus or genus Pseudomonas. In this study growth of bacteria P. fluorescens AM PS11 culture in locally obtained clay is studied for the purpose of establishing their influence on rheological properties of clay. An attempt to evaluate it has been made using FT-IR and XRD. Change in plasticity of clay using Atterberg limits method …
Effect of sintering process and additives on the properties of cordierite based ceramics
2013
It is possible to obtain cordierite ceramics with high temperature synthesis using both synthetic and raw natural materials. This paper discusses the possibilities to obtain cordierite ceramics, replacing part of required oxides with raw materials from various Latvian deposits of dolomite and clay. The obtained raw cordierite powders were ground in two modes (3 and 12 hours) and fired at 1200 °C. Ceramic samples were characterized by hydrostatic weighting method; crystalline phase composition was studied by XRD. Obtained samples were evaluated by their mechanical (compressive) strength and linear coefficient of thermal expansion (CTE). Thermal shock resistance was tested using water quenchi…