Characteristics of Thermal Parameters and Some Physical Properties of Mineral Eutectic Type: Petalite–Alkali Feldspars

The aim of the research was to check whether the system of three fluxes based on lithium aluminium silicate and alkali feldspars has a eutectic point, i.e., with the lowest melting temperature. Lithium was introduced into the mixtures in the form of petalite, which occurs naturally in nature (Bikita Zimbabwe deposit). Using naturally occurring raw materials such as petalite, sodium feldspar, and potassium feldspar, an attempt was made to obtain eutectics with the lowest melting point to facilitate thermal processing of the mineral materials. In addition, the high-temperature viscosity of the mineral alloys and physical parameters such as density, linear shrinkage, and open porosity were studied. The study showed that in these systems, there is one three-component eutectic at 1345 °C, with the lowest viscosity of 1·105 Pas and the highest density of 2.34g/cm3, with a weight content of petalite 20%, sodium feldspar 20%, and potassium feldspar 20%.

Utilization of Porcelain Tile Polishing Residue

The research focuses on the properties of by-products formed in the production of porcelain stoneware: polishing residue and residue of the mixture-preparation shop. The polishing residue consists of glassy phase (80%), quartz (14%), mullite (5%). Residue of the mixture-preparation shop consists of quartz (~ 18%), muscovite (~ 6.9%), kaolinite (~ 20.5%), calcium-sodium feldspar (~ 51.4%), diopside (~ 2.98%). Polishing residue occurs when polishing porcelain stoneware to create a glossy surface and when polishing the side faces of porcelain stoneware to obtain accurate tile geometry. The particle size of the polishing residue is less than 0.2 mm, and the residue of the mixture-preparation shop is less than 40 microns. Residue of the mixture-preparation shop is formed when cleaning equipment: mills, mixers, slipways, etc. The ways of utilization of by-product are follows: as a filler for the silicate production; for polymer-cement, water-dispersion and oil paints; as a filler for the production of roofing materials, bituminous roofing mastics based on organic binders; raw materials for the production of foam glass materials and products.

Silicate Mineral Eutectics with Special Reference to Lithium

In this paper, the system of natural mineral alkali fluxes used in typical mineral industry technologies was analyzed. The main objective was to reduce the melting temperature of the flux systems. Particular attention was paid to the properties of lithium aluminium silicates in terms of simplifying and accelerating the heat treatment process. In this area, an alkaline flux system involving lithium was analyzed. A basic flux system based on sodium potassium lithium aluminosilicates was analyzed; using naturally occurring raw materials such as spodumene, albite and orthoclase, an attempt was made to obtain the eutectic with the lowest melting point. Studies have shown that there are two eutectics in these systems, with about 30% spodumene content. The active influence of sodium feldspar was found.

Utilization of diverse cheap materials as pore generating agent to manufacture low-cost porous ceramic

Paper waste, corn starch, and sawdust were utilized as pore generating agents to produce a porous ceramic. Kaolin clay, sodium feldspar, and 20% of pore generating agent were mixed, and the samples were formed by mold method, dried at room temperature for about 72 h and in a furnace at 115 ºC for 5 h, and then fired at 1200 ºC with a soaking time of 3 h. The samples were tested for measurement of physical and mechanical properties and the microstructure was evaluated by scanning electron microscopy and mercury intrusion porosimetry. The results showed that the sample prepared with corn starch had the highest porosity, lowest mechanical properties and permeability, and smallest pore size, while the characteristics of the sample prepared with sawdust were contrary; finally, the sample of paper waste had the highest permeability and intermediate values of other properties.

Rare earth ion Tb3+ doped natural sodium feldspar (NaAlSi3O8) Luminescent properties and energy transfer

In this study, Tb3+—doped natural sodium feldspar (NaAlSi3O8) phosphors have been successfully prepared using high−temperature solid—state method with natural sodium feldspar as a substrate. Energy—dispersive X—ray spectrometry analysis (EDX) of NaAlSi3O8 showed that 0.03 wt% of Eu element was present, and elemental distribution mapping analysis showed that the distribution of trace Eu in minerals was aggregated. The crystal structure and luminescence properties of the natural sodium Eu—containing feldspar and synthetic sodium feldspar NaAlSi3O8:Eu3+, Tb3+ phosphors are discussed in detail. The crystal structure analysis of the samples showed that the Na+ in the natural matrix was partly replaced by the doped Tb3+. Studies on the photoluminescence properties of the samples indicate that Eu does not form a luminescent center in the natural mineral, however, the strong characteristic peak of Eu3+ at 615 nm appears after doping with Tb3+ and the peak at 615 nm increases with the increase of Tb3+ concentration. According to the above spectral results, the energy transfer from Tb3+ to Eu3+ is obtained. Through the measurement and analysis of color coordinates, it is found that with the increase of Tb3+ concentration, the luminescence color of the samples can be regulated in the green to red region. NaAlSi3O8:Eu3+ Tb3+ phosphors has potential application value.

Effect of bentonite addition on some properties of porcelain

Porcelain is one of the most important ceramic materials with a wide range of traditional and technical applications. Since most mixtures of porcelain have a high sintering temperature, bentonite has been added in this research to improve the characteristics of sintering and burning. The porcelain mixture consisted of the following Iraqi raw materials: 30% wt kaolin, 30 wt% non-plastic clay (grog), 10% wt sodium feldspar, 10 wt% potassium feldspar and 20 wt% flint. After the mechanical mixing process and transfer the powder mixture to the slurry by adding distilled water, then different weight percentage of the sodium bentonite(0, 2.5, 5, 7.5 and 10) wt% was added. The specimens were prepared by using the solid casting method, and after the drying process, the specimens were burned at1100 oC. The results of x-ray diffraction showed that bentonite reduced the crystallization of the main ceramic phases (mullite, quartz), which stimulates the appearance of amorphous glass phases. Also, the loss of mass on ignition increased when the addition of bentonite from 5.66% to 8.2%. There was also a great convergence between the granules of porcelain when adding bentonite and thus increase the shrinkage of the dimensions from 9.33% to 12.37 %. This led to increasing the bulk density from 1.97 g/cm3 to 2.67 g/cm3 at firing temperature 1100oC, and the porosity was decreased from 17.1% to 1.44%. Diametrical strength and flexural strength (bending) increased with bentonite (14.88 to 34.46MPa), (6.2 to 8.65 MPa), respectively.

Study of Porcelain Vitreous Phase Viscosity to Obtain Curve Ceramic Coatings

The porcelain materials are composed of crystalline particles immersed in a vitreous matrix. This study has aimed to calculate the porcelain’s vitreous phase viscosity through the Vogel-Fucher-Tamman equation, VFT, to obtain eventually curved coating. We’ve formulated a standard mass, and over it we’ve added the proportions of 4, 8 and 15% of sodium feldspar, main former of the liquid phase, in order to verify its influence over the viscosity at the final vitreous phase. Concerning the standard mass, the addition of 4 and 8% has provoked a reduction of viscosity, while the addition of 15% resulted in a rise of viscosity. Because porcelain does not present a homogenous vitreous phase and crystalline particles, the VFT equation may have given us relative viscosity values. However, these values are coherent with glasses containing sodium, if one assumes that the crystalline phases have no influence over the system and that the vitreous phase has a homogenous composition.

Development of Engobe Samples for Dan Kwian Ceramic Body

This paper developed engobe samples for Dan Kwian ceramic body. Kaolinite clay, zirconium silicate, sodium feldspar and quartz were used as raw materials which were varied to obtain various samples. Mix proportion was designed by the square sampling method to obtain 16 samples. All samples were milled and fired at 1200°C under oxidation and reduction atmospheres. The results showed that the suitable engobe composition of kaolinite clay 10 wt%, zirconium silicate 10 wt%, sodium feldspar 40 wt% and quartz 40 wt% to produce good surface appearance for Dan Kwian ceramics. Engobe surfaces and the body had no defect both in the oxidation and reduction atmospheres. The color and engobe surface were opaque white and glossy, respectively.

Research on Volcanic Rock Types and Characteristics in Ou Area

Through core observation and description, whole rock chemical analysis, thin section identification and logging identification method, The volcanic rock of this area is mainly basalt, trachyte and tuff, three major categories, further divided into 10 subclasses. Basalt intergranular-intersertal structure, the main minerals are plagioclase , sodium feldspar and mafic pyroxene , belong to alkaline series,infrasonic wave, low natural gamma, high resistance, high density; Trachyte ,typical rough structure, high content of feldspar, the negative anomaly of naturalelectric potential, high resistance, high natural gamma measurement, infrasonic wave;Tuff, tuffaceous texture, massive structure, rock is composed of lithic, vitric, crystal and volcanic ash, ingredients to alkali feldspar, biotite, plagioclase etc, low natural gamma, low resistivity , low density.