Porous Ceramics Adsorbents Based on Glass Fiber-Reinforced Plastics for NOx and SOx Removal

To reuse waste glass fiber-reinforced plastics (GFRPs), porous ceramics (i.e., GFRP/clay ceramics) were produced by mixing crushed GFRP with clay followed by firing the resulting mixture under different conditions. The possibility of using ceramics fired under a reducing atmosphere as adsorbent materials to remove NOx and SOx from combustion gases of fossil fuels was investigated because of the high porosity, specific surface area, and contents of glass fibers and plastic carbides of the ceramics. NO2 and SO2 adsorption tests were conducted on several types of GFRP/clay ceramic samples, and the gas concentration reduction rates were compared to those of a clay ceramic and a volcanic pumice with high NO2 adsorption. In addition, to clarify the primary factor affecting gas adsorption, adsorption tests were conducted on the glass fibers in the GFRP and GFRP carbides. The reductively fired GFRP/clay ceramics exhibited high adsorption performance for both NO2 and SO2. The primary factor affecting the NO2 adsorption of the ceramics was the plastic carbide content in the clay structure, while that affecting the SO2 adsorption of the ceramics was the glass fiber content.

Heating Rate Effect during Sintering on the Technological Properties of Brazilian Red Ceramics

Unbalanced energy consumption in the production of ceramic artifacts is responsible for considerable undesirable impacts, such as increased emissions of polluting gases, excessive consumption of fuel materials, land degradation and unpredictable financial costs. By contrast, the practice of optimizing the ceramic sintering, which in associated with firing of high temperature, can result in increased productivity and reduced production costs preserving an environmentally friendly production system. Moreover, it allows further improvements in the quality of the final product. This work compares the effect of different sintering cycles, with heating rates of 2, 15 and 30°C/min, on the technological properties of a Brazilian industrial clay ceramic body. Initially the clay ceramic specimens was characterized in terms of mineralogical, chemical and physical properties. Specimens were prepared by extrusion and fired at temperatures of 800, 900 and 1000°C. The evaluated properties by standard tests were water absorption, post-firing linear shrinkage and flexural strength. It was found that owing to sintering carried out at higher heating rates, red ceramic products with superior technological properties were obtained. This is an unprecedented conclusion for common clay ceramics produced in Brazil. Based on the promising obtained results it is evidenced, in a clear and detailed way, the benefits of rapid sintering cycle application for conventional brick production.

Problems of Furnace Arc Brick Dating according to Materials of Klimetovski Archaeological Excavations in Pskov (2016)

В статье подробно разбираются возможности датирования печной красноглиняной керамики на примере одного раскопа. В целом хронология печных дуг охватывает период с XV по начало XVII в. Массовое их производство приходится на XVI век The article analyzes the dating of furnace red clay ceramics on the example of one excavation. In general, the chronology of furnace arcs covers the period from the 15 to the beginning of the 17 century. Their mass production falls on the 16 century

White Clay Ceramic Tableware Waste as Coarse Aggregate in Concrete - Some Mechanical Properties and Durability against Fire and Sulfate Attack

The aim of study is to produce durable structural concrete by using waste ceramics with specified type (white clay ceramics) as coarse aggregates in concrete. Mechanical properties were studied, the study also show good resistance to fire resistance for concrete contains ceramics as coarse aggregates compared with normal aggregates concrete, good mechanical properties such as compressive, tensile, and flexural strength. Results of study gave 17.5% increment in compressive strength by using 100% replacement of waste ceramic, flexural strength increased with 27.8% increment. Study also show less reduction in strength due to fire resistance by using waste ceramics compared to ordinary concrete, and also more durable concrete for salty water effects by using ceramic.

Microstructural characterization of ceramic artifacts made using the raku technique

This study was carried out at the atelier “Adamas”, located in the city of Cunha, in the state of São Paulo, Brazil. The objective is to characterize the physical and mechanical properties of ceramics made using the raku technique in the Adamas atelier. As a methodology, the specimens were submitted to the following tests: Scanning Electron Microscopy (SEM), X-ray Energy Dispersion Spectroscopy (EDS), mass loss and linear shrinkage. It was observed that the specimens were mainly composed of silicon and aluminum, which is typical of ceramics made with kaolinitic clays, possessing a plastic behavior for molding and after firing refractory. Therefore, ceramic artifacts made through the raku technique have typical chemical and physical characteristics of clay ceramics, proper adhesion of the glaze even when there are crackles originated purposely from the process, which causes the artistic artifact appropriate characteristics for use and appreciation.

Preparation of Low-Dielectric-Constant Kaolin Clay Ceramics by Chemical Cleaning Method

Kaolin clay is an inexpensive and abundant material with potential for use as a low-dielectric-constant ceramic; however, the natural metallic oxides the clay contains hinder such applications. In this study, kaolin clay ceramics with excellent physical and dielectric properties were synthesized using kaolin clay as the raw material by chemical cleaning and sintering. Characterization of the resulting samples showed that the sulfuric acid treatment has a significant influence on the metallic oxide content and dielectric properties of the kaolin clay ceramics. When the kaolin clay raw material was treated with sulfuric acid three times, the dielectric constant decreased from 5.12 to 3.75 and the Vickers hardness increased from 946 to 1,214 kg/mm2 relative to the ceramic prepared from the untreated clay. Therefore, these ceramics exhibit significant potential for use in the microelectronics industry.