scholarly journals Mining Wastes of an Albite Deposit as Raw Materials for Vitrified Mullite Ceramics

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 232
Author(s):  
Pedro J. Sánchez-Soto ◽  
Eduardo Garzón ◽  
Luis Pérez-Villarejo ◽  
George N. Angelopoulos ◽  
Dolores Eliche-Quesada

In this work, an examination of mining wastes of an albite deposit in south Spain was carried out using X-ray Fluorescence (XRF), X-ray diffraction (XRD), particle size analysis, thermo-dilatometry and Differential Thermal Analysis (DTA) and Thermogravimetric (TG) analysis, followed by the determination of the main ceramic properties. The albite content in two selected samples was high (65–40 wt. %), accompanied by quartz (25–40 wt. %) and other minor minerals identified by XRD, mainly kaolinite, in agreement with the high content of silica and alumina determined by XRF. The content of Na2O was in the range 5.44–3.09 wt. %, being associated with albite. The iron content was very low (<0.75 wt. %). The kaolinite content in the waste was estimated from ~8 to 32 wt. %. The particle size analysis indicated values of 11–31 wt. % of particles <63 µm. The ceramic properties of fired samples (1000–1350 °C) showed progressive shrinkage by the thermal effect, with water absorption and open porosity almost at zero at 1200–1250 °C. At 1200 °C, the bulk density reached a maximum value of 2.38 g/cm3. An abrupt change in the phase evolution by XRD was found from 1150 to 1200 °C, with the disappearance of albite by melting in accordance with the predictions of the phase diagram SiO2-Al2O3-Na2O and the system albite-quartz. These fired materials contained as main crystalline phases quartz and mullite. Quartz was present in the raw samples and mullite was formed by decomposition of kaolinite. The observation of mullite forming needle-shape crystals was revealed by Scanning Electron Microscopy (SEM). The formation of fully densified and vitrified mullite materials by firing treatments was demonstrated.

Author(s):  
Fredy Kurniawan ◽  
Rahmi Rahmi

SnO2 nanoparticles have been synthesized by high voltage electrolysis. Tin bare was used for anode and cathode. The effect of potentials and electrolyte were studied. The particles obtained after electrolysis was characterized using X-ray Diffraction (XRD). The diffractogram is in agreement with the standard diffraction pattern of SnO2 which is identified as tetragonal structure. The Fourier Transform Infrared (FTIR) spectrum indicates that there is a vibration of Sn–O asymmetric at 580 cm-1. The optimum potential for SnO2 nanoparticles synthesis is 60 V at 0.06 M HCl which shows the highest UV-Vis spectrum. The absorption peak of SnO2 nanoparticles by UV-Vis spectrophotometer appears at about 207 nm. The particle size analysis shows that the SnO2 nanoparticles obtained have the size distribution in a range of 25-150 nm with the highest volume at 83.11 nm. Copyright © 2017 BCREC Group. All rights reservedReceived: 15th November 2016; Revised: 26th February 2017; Accepted: 27th February 2017How to Cite: Rahmi, R., Kurniawan, F. (2017). Synthesis of SnO2 Nanoparticles by High Potential Electrolysis. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (2): 281-286 (doi:10.9767/bcrec.12.2.773.281-286)Permalink/DOI: http://dx.doi.org/10.9767/bcrec.12.2.773.281-286 


1989 ◽  
Vol 169 ◽  
Author(s):  
Rollin E. Lakis ◽  
Sidney R. Butler

AbstractY1Ba2Cu3O7 has been prepared by the evaporative decomposition of solutions method. Nitrate and mixed anion solutions were atomized and decomposed at temperatures ranging from 300°C to 950°C. The resulting materials have been characterized using x-ray powder diffraction, Thermal Gravimetric Analysis (TGA), particle size analysis, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The powder consists of 0.3 micron agglomerated hollow spheres with a primary particle size of 0.06 micron. TGA and x-ray diffraction indicate the presence of barium nitrate and barium carbonate due to incomplete decomposition and/or product contamination by the process environment.


2015 ◽  
Vol 1109 ◽  
pp. 314-318
Author(s):  
Nor Diyana Abdul Aziz ◽  
Kelimah Elong ◽  
Norlida Kamarulzaman

Tin Oxide (SnO2) is a metal oxide which has many applications in industry. In this study, SnO2 powders were synthesized by a self-propagating combustion (SPC) method. The product was annealed at 800 °C for 12 and 24 h before characterizing with X-Ray Diffraction (XRD) for phase studies. X-Ray Diffraction results showed that both samples are pure of tetragonal structure with space group P42/mnm. The sample annealed at a longer period, that is, 24 h, shows a higher degree of crystallinity compared to the 12 h annealed sample. It also shows a smaller full width at half maximum (FWHM), indicating larger crystallite size for the 24 h annealed sample. The particle size analysis reveals that there are two groups of particle size distributions for both samples. SEM results give values that are different from the particle sizer results due to the different nature of the measurement methods.


Clay Minerals ◽  
2009 ◽  
Vol 44 (3) ◽  
pp. 311-317 ◽  
Author(s):  
J. Bonifacio-Martínez ◽  
J. Serrano-Gómez ◽  
Ma. Del Carmen López-Reyes ◽  
F. Granados-Correa

AbstractThe effects of mechano-chemical treatment on the surface characteristics and sorption properties of hydrotalcite were studied. Non-milled (crushed) and milled samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size analysis and specific area. A milling time of 2 h decreased the particle size of the hydrotalcite samples from 21 to 8.0 nm, the specific area from 97 to 5.7 m2 g–1 and the total pore volume from 0.41 to 0.01 cm3. After the crushed and milled samples had been separately calcined at 500ºC, they were agitated with 10–2 M Na2MoO4 aqueous solutions for 48 h. The molybdate ion content in the regenerated non-milled hydrotalcite samples (HTc-MoO4) was found to be 6.0 meq g–1 while in the milled hydrotalcite (HTm-MoO4) samples this content was 2.5 meq g–1. The lower molybdate content was thought to be a result of compaction and, hence, reduced reactivity of the milled HT samples.


2013 ◽  
Vol 1 (1) ◽  
pp. 11-14
Author(s):  
N. Sahu ◽  
◽  
R. K. Duchaniya ◽  

The ZnO-CdO nanocomposite was prepared by sol-gel method by using their respective nitrates. It is a simple and low cost method to prepare nanocomposites. The drying temperature and drying period of prepared gel was varied during the synthesis process. The prepared samples were characterized by using scanning electron microscope (SEM), particle size analysis (PSA), X-ray diffraction (XRD) and photoluminescence spectroscopy (PL) to get surface morphology, idea of getting particle of nanosized range so that further characterizations can be done, to study the optical property of synthesized nanocomposite and measure the band gap . The grain size determined by Scherrer’s formula was found to be between 30-50 nm.


Author(s):  
Antonio Augusto Sousa ◽  
Hilda Camila Nogueira ◽  
Gabriela de Castro Araújo ◽  
Felipe Augusto Sousa ◽  
Alisson Rufino Andrade

The processing of ornamental rocks promotes the constant generation of abrasive sludge, which, in turn, causes different types of contamination. The possibility of reusing residues generated in industrial processes has economic advantages, therefore, it is necessary to know the physical, chemical and mineral properties of these residues. Thus, the objective of this research was to evaluate the possibilities of application of abrasive mud, generated in industries located in the city of Campina Grande - PB, based on its main characteristics. The methodology consisted of the following analyzes: X-ray fluorescence, X-ray diffraction, scanning electron microscopy, particle size analysis and physical-chemical analysis. Chemical analyzes revealed that the residues have interesting characteristics, mainly for use in civil construction. The mineralogical analysis indicated that the sample has an essential mineral composition for the cosmetic industry, which was confirmed by the detected elements present. The study of the particle size characterized the sample as material of irregular shape and with good micronization, confirming the potential for reuse as a cosmetic, while the morphological analysis showed the presence of iron as a limiting factor for certain applications. Physico-chemical tests confirmed the characteristics common to abrasive sludge. The characterized samples showed, in general, satisfactory properties with regard to its use as an alternative material in different segments.


Author(s):  
Mwendwa Geoffrey ◽  
Motochi Isaac ◽  
Otieno Fredrick

This study aimed at evaluating Matisaa gray rock (MGR) for clinker production. MGR is naturally abundant in Matisaa, a rural area in Mwingi West District, Kitui county, Kenya. It is locally used as a gabion filler and other concrete structures with desirable physico-mechanical properties. This research employed a controlled experimental design to determine the clinker qualification of MGR. This was based on particle size analysis and raw meal moduli. The standard sieve tests and a Blaine meter were used in the determination of particle size while the raw meal moduli were determined from the respective cement oxides in MGR, which were determined using wavelength dispersive X-ray fluorescence (WDXRF) spectrometer. It was observed that 69.65% of the particle size composition of MGR was less than 90 . Out of this composition, 71.60% of the particle sizes were less than 45 , contributing to a specific surface area of 292.5 . The hydraulic modulus (2.05 – 2.61) and lime saturation factor (0.87 – 0.98) are quite desirable though the silica and alumina ratios are higher than the standard range due to the low proportions of  and  content. The sulfatisation modulus is also undesirable due to the high content of . Thus, without beneficiation, Matisaa gray rock would lead to the production of low-quality clinker. However, the general parametric comparison of Matisaa gray rock with Konza shows that it has the potential for utilization as a clinker raw material.


Author(s):  
YULIANITA PRATIWI INDAH LESTARI ◽  
HERMAN SURYADI ◽  
MIRAJUNNISA ◽  
WIBOWO MANGUNWARDOYO ◽  
SUTRIYO ◽  
...  

Objective: This study aimed to increase the yield of microcrystalline cellulose (MCC) from kapok pericarpium alpha-cellulose produced by enzymatic hydrolysis using purified cellulase from Termites (Macrotermes gilvus) and to compare the characteristics with the reference product. Methods: In this research, MCC was prepared from kapok pericarpium powder through the chemical isolation process of alpha-cellulose, followed by enzymatic hydrolysis with purified cellulase from Macrotermes gilvus. The yield was improved by using purified cellulase in optimized temperature, pH, and hydrolysis time. Identification was carried out by using ZnCl and infrared spectrophotometry, followed by characterization of MCC include particle size analysis (PSA) and diffracto­gram pattern (X-Ray Diffraction). The results were compared with Avicel PH 101 as the reference product. Results: Purified cellulase from Macrotermes gilvus showed high cellulose activity. Cellulose in the concentration of 11.743 U/ml formed 49 mm clear zone area with cellulolytic index 7.16 that similar to the formed clear zone area of Trichoderma reesei (50 mm), the optimum hydrolysis condition was achieved at 50 °C, pH 6.0, in 2 h, which produced 80% yield of MCC. Produced MCC was analyzed with ZnCl and FTIR spectrum resulting in positive results, similar to reference. The results of the organoleptic test, particle size analysis, and diffracto­gram pattern (X-Ray Diffraction) showed crystalline characteristics of MCC is similar to the reference (Avicel PH 101). Conclusion: Cellulase Macrotermes gilvus yielded 80% MCC and higher enzymatic activity than Trichoderma reesei. Based on the organoleptic test, particle size analysis, and diffracto­gram pattern observation, MCC from kapok pericarpium has shown similar characteristics to reference (Avicel pH 101) and might be potential to be further developed.


Author(s):  
HERMAN SURYADI ◽  
YULIANITA PRATIWI INDAH LESTARI ◽  
MIRAJUNNISA ◽  
ARRY YANUAR

Objective: This study aimed to increase the yield of microcrystalline cellulose (MCC) made from water hyacinth ɑ-cellulose by enzymatic hydrolysis by using purified enzyme and to find it’s characteristics compared to the reference. Methods: In this research, MCC was prepared from water hyacinth powder through the chemical isolation process of ɑ-cellulose, followed by enzymatic hydrolysis with purified cellulase from Chaetomium globosum. The yield of MCC was improved by using purified enzyme and optimization of temperature, pH, and hydrolysis time. Identification was carried out by using ZnCl and infrared spectrophotometry, followed by characterization of MCC include particle size analysis (PSA) and diffracto­gram pattern (X-Ray Diffraction) compared to reference Avicel PH 101. Results: Purified enzyme from Chaetomium globosum has high activity with a clear zone area of 45 mm with cellulolytic index 6.5 that almost same as Trichoderma reesei (50 mm), with the cellulase enzyme activity of 6.691 U/ml. The optimum condition was at a temperature of 50⁰C and pH 6.0 with the hydrolysis time of 2 h, which produced 95% yield of MCC. Identification with ZnCl and FTIR spectrum showed positive results, similar to the reference. The results of organoleptic test, particle size analysis, and diffracto­gram pattern (X-Ray Diffraction) showed crystalline characteristic similar to reference (Avicel PH 101). Conclusion: Enzyme from Chaetomium globosum has a higher activity of cellulase than Trichoderma reesei with MCC obtained was 95%. Based on the comparison of the organoleptic test, particle size analysis, and diffracto­gram pattern, MCC from water hyacinth has a great potential which showed similar characteristic to reference (Avicel pH 101).


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