Feasibility Study on the Potential Replacement of Primary Raw Materials in Traditional Ceramics by Clayey Overburden Sterile from the Prosilio Region (Western Macedonia, Greece)

The objective of this study was to investigate the valorization potential of clayey overburden sterile materials from lignite-mining activities in the manufacturing of traditional ceramics. This study aims to contribute toward the sustainable management and use of such waste materials in line with the environmental objectives of the 2030 agenda. To assess this issue, clayey steriles were incorporated in a white clay-body at 20, 50, and 80 wt%, whereas reference samples were also formed from the individual raw materials. Laboratory processing of the ceramics was performed by dry pressing loose powder into rectangular samples and firing at 1000 °C for 4 h. Characterization of the raw materials included chemical, mineralogical, and thermal analysis. The fired bodies were tested for their total linear shrinkage, apparent porosity, water absorption, bulk density, and bending strength according to the relevant standards. The microstructural evolution of the final bodies was analyzed by scanning electron microscopy, which observed differences related to the addition of the steriles. The results showed that the tested clayey steriles can be utilized up to 50 wt% as a secondary raw material in the production of ceramic materials (e.g., bricks) with comparable properties to the reference clay-bodies. Furthermore, the color of the final samples changed from white-creamy to reddish as the content of clayey sterile materials increased in the raw mix.

Ceramic bricks with enhanced thermal insulation produced from natural zeolite

In this research, ceramic bricks were produced based on natural zeolite from Tokaj (Hungary) using the dry pressing technique. The microstructure, morphology and properties of the produced samples were examined via scanning electron microscopy, X-ray diffraction and X-ray fluorescence. The X-ray investigation revealed various minerals in the natural zeolite; moreover, the samples’ physical and thermal properties were also investigated. The sintering temperature and composition play a major role in the microstructure and the properties of the prepared ceramic samples. The produced ceramics bricks have excellent thermal insulation and good mechanical strength. The results of this research work confirm the potential use of natural zeolite from Tokaj as an eco-friendly building material.

Baryshok. Enriching colour range of ceramic shapes on clay-based materials of low quality

Introduction. This article discusses the possibility of expanding the colour palette of a ceramic shard. Due to the shortage of high-quality clay raw materials for the manufacture of plastic molded facing bricks, the problem of manufacturing ceramic wall materials by semi-dry pressing from low-quality clay rocks is urgent.Materials and methods. The main raw material was non-caking clay raw material with a low content of clay and a high content of silt particles. Some corrective additives were used to expand the colour palette of ceramic bricks. In the article, the authors used both standard methods for determining the physical and mechanical properties and modern methods for studying the phase composition of materials.Results. The possibility of enriching the colour range of a ceramic shard based on non-sintered clay raw materials has been experimentally confirmed, provided that the mixture contains flux additives. When receiving products with a clarified shard, light-colored flutes should be used.Conclusion. The possibility of enriching the colour range of a ceramic cap by adding white-burning clay, introducing bleaching and chromophore additives and technogenic products has been established. Due to the differences in the chemical composition of clay raw materials from individual deposits, an individual approach to each of them is required.

Production Ceramic Crude Petroleum Filters from Local Raw Materials

Crude petroleum filters were prepared from low-cost materials based on kaolin powder and combustible materials as palm fronds powder which acts as pore creating agent. The samples with different content (10, 20, 30,40) wt% of palm fronds powder (P.F) were fabricated using a dry pressing method and fired at 1100 °C. Crude petroleum filters were characterized by X-ray diffraction (XRD), energy dispersive analysis (EDS) and Scanning electron microscopy (SEM). Physical properties (linear shrinkage, apparent porosity, water absorption, apparent density), mechanical properties (compressive strength and diametrical strength ) and Metallic Content.

Ceramic Tiles Production from Cullet and Agricultural Wastes Obtained from Wheat and Sugarcane Cultivation

Agricultural wastes are a big source for environmental pollution so it’s a good choice to recycle them so as to get an environmental and economic benefit. The purpose of this research is to determine the possibility of recycling two types of agriculture wastes obtained from wheat and sugarcane cultivation in addition to broken glass (cullet) as raw materials for ceramic wall tiles production. The used agriculture wastes are the agricultural residue obtained from wheat and sugarcane cultivation. The experimental work starts with performing XRF and sieve analysis for all raw materials. Ceramic wall tiles specimens were made with dimensions 110.4 × 55.4 × 8 mm3 using 27 MPa dry pressing then dried at 120 oC overnight, then fired using firing temperatures equal to 1100 oC or 1150 oC during 15 min soaking time. Water absorption, apparent porosity, and mechanical properties were done to compare them with ISO standards. According to the previous experimental work, it was found that the samples with the composition (10% Cullet, 15% Wheat ash straw, 20% sugarcane) for samples that fired at 1150 oC or (10% Cullet, 13% Wheat ash straw, 18% sugarcane) for samples that fired at 1100 oC has the optimum properties.

Influence of forming pressure on frost resistance of ceramics

The object of research is low-melting clays of the Kyiv region (Ukraine). The work is devoted to the study of obtaining ceramic materials resistant to low temperatures. Frost resistance is one of the most important characteristics for regions in which ceramic materials are used with frequent temperature transitions through 0 °C. The production of frost-resistant ceramic wall materials is determined by the type of raw materials and technological production parameters. The main technological methods for increasing frost resistance are: the use of less dispersed clays; batch homogenization; formation of raw material without textural defects and prevention of cracks during drying and firing. The work shows that the existing methods for increasing frost resistance can be implemented by reducing water absorption due to the creation of a microporous structure with predominantly closed pores by increased pressure of a semi-dry method of formation. An increase in the pressing pressure leads to an increase in the number of contacts of the molecules of the ceramic mass at the stage of formation. Due to this, the strength of the molded samples at a pressing pressure of more than 30 MPa is higher compared to samples molded by the plastic method. It was also found that an increase in the pressing pressure makes it possible to speed up the drying process of ceramic products, reducing energy consumption for their production. Due to an increase in the pressing pressure to 50 MPa, the strength of samples obtained by semi-dry pressing is 55.4 MPa, while for samples during plastic formation it is 22.9 MPa. Water absorption, on the contrary, for dry pressing is 9.3 %, while for plastic pressing it is 12.2 % at a firing temperature of 1000 °C. It is shown that increasing the pressing pressure is an effective way to improve the quality of ceramic materials based on local low-plasticity clay raw materials. Saving natural and energy resources, developing new sources of raw materials and comprehensive improvement of products with environmental friendliness of production remain important today.

Recycling of Cullet, Waste Clay Bricks and Wastes Resulted from Wheat and Sugarcane Cultivations in the Manufacture of Fired Clay Bricks

The agriculture wastes are considered as a big environmental problem. The main purpose of this research is to determine the possibility of producing fired clay bricks from a mixture of agriculture wastes in addition to other wastes. The first type of wastes is the cullet while the second type is the wastes is the waste clay bricks (Homra) and the third is an agricultural residue obtained from wheat and sugarcane cultivation. The first step of the experimental work is performing XRF and sieve analysis for raw materials. Brick samples with Cubic shape with dimensions 50 × 50 × 50 mm3 were formed by 1 MPa dry pressing then drying at 120 oC overnight. Tile samples were fired at temperatures of 850 oC for 15 min soaking time. Water absorption, apparent porosity, and mechanical properties were determined and compared to ES 4763 / 2006 and ASTM C 62 / 2013 standards. According to the previous experimental work, it was found that the samples that has a composition (38 % Desert clay, 20% Homra, 10% cullet, 15% Wheat ash straw, 17% sugarcane) has the optimum properties with respect to ES 4763 / 2006 and ASTM C 62 / 2013 standards.