scholarly journals Preparation of β-belite using liquid alkali silicates

2017 ◽  
Vol 67 (328) ◽  
pp. 140 ◽  
Author(s):  
P. Koutník
Keyword(s):  
Silica Fume ◽  
Raw Materials ◽  
Mineralogical Composition ◽  
Potassium Silicate ◽  
X Ray Diffraction ◽  
Free Lime ◽  
Burning Temperature ◽  
Lime Content ◽  
Powdered Limestone ◽  
Alkali Silicates

The aim of this study is the preparation of β-belite by a solid-state reaction using powdered limestone, amorphous silica and liquid alkali silicates. The raw materials were blended, the mixtures were agglomerated and then burnt. The resulting samples were characterized by X-ray diffraction analysis and scanning electron microscopy. Free lime content in the β-belite samples was also determined. The effects of CaO/SiO2 ratio (1.6–2.1), burning temperature (800–1400 °C), utilization of different raw materials (silica fume, synthetic silica, potassium silicate, sodium silicate, potassium hydroxide) and burning time (0.5–16 h) on free lime content and mineralogical composition were investigated. The purest ?-belite samples were prepared from a mixture of powdered limestone, silica fume and liquid potassium silicate with a ratio CaO/SiO2 = 2 by burning at temperatures between 1100 and 1300 °C for more than 2 h. Decreasing of the CaO/SiO2 ratio led to rankinite formation and lower a burning temperature led to the formation of wollastonite.

scholarly journals Physicochemical Properties of Handere Clays and Their Use as a Building Material

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Yasin Erdoğan
Keyword(s):  
Physicochemical Properties ◽  
Building Materials ◽  
Raw Materials ◽  
Organic Matter Content ◽  
Volcanic Glass ◽  
Mineralogical Composition ◽  
Matter Content ◽  
Loss On Ignition ◽  
X Ray Diffraction ◽  
Clay Deposits

Handere clay deposits were discovered at Adana in Turkey. These clay units primarily consist of uncoloured claystone, pebbly sandstone, sandstone, siltstone, and mudstone marl and include gypsum lenses and clay levels of various thicknesses in places. The physicochemical properties of these clays have been investigated by different techniques including Scanning Electron and Elemental Analysis (SEM and EDS), mineralogical analyses, chemical and physical analyses, X-ray diffraction (XRD), thermogravimetric differential thermal analysis (TG-DTA), and Atterberg (Consistency) Limits Test. The mineralogical composition deduced from XRD is wide (smectite + palygorskite + illite ± feldspar ± chlorite ± quartz ± calcite ± serpentine) due to the high smectite contents (≈85%). SEM studies reveal that smectite minerals are composed of irregular platy leaves and show honeycomb pattern in the form of wavy leaves in places. The leaves presenting an array with surface edge contact are usually concentrated in the dissolution voids and fractures of volcanic glass. Organic matter content and loss on ignition analysis of raw materials are good for all the studied samples. In summary, Handere clays can be used as building materials in bricks, roof tiles, and cement and as a binder.

Mineralogical and physicochemical characterization of selected Portuguese Mesozoic-Cenozoic muddy/clayey raw materials to be potentially used as healing clays

Clay Minerals ◽  
2010 ◽  
Vol 45 (2) ◽  
pp. 229-240 ◽  
Author(s):  
M. Rebelo ◽  
F. Rocha ◽  
E. Ferreira Da Silva
Keyword(s):  
Physicochemical Properties ◽  
Mineral Water ◽  
Raw Materials ◽  
Physicochemical Characterization ◽  
Mineralogical Composition ◽  
Exchange Capacity ◽  
Water Mixture ◽  
X Ray Diffraction ◽  
Geological Formations

AbstractThe use of pelitic geological materials for the treatment of muscle-bone-skin pathologies, by application of a cataplasm made of clay and mineral water mixture, is currently receiving attention and interest from the general public and scientific community. In Portugal there are several natural occurrences of clays/muds which are used for pelotherapy and/or geotherapy. These are carried out either indoors (thalassotherapy and thermal centres) or outdoors, in natural sites generally located near the seaside. The aim of this study is to assess the mineralogical and physicochemical properties of Portuguese raw materials for therapeutic purposes. These materials were collected from different Portuguese Mesozoic-Cenozoic geological formations located in the neighbourhood of thermal centres or at beaches known from their empirical applications. X-ray diffraction (XRD) and scanning electron microscopy (SEM-EDS) were used to assess the mineralogical composition of these clays. Physicochemical properties, such as specific surface area, cation exchange capacity, plasticity/abrasiveness indices and heat diffusiveness were also determined. Having distinct geological ages and genesis, the materials examined are mainly illitic. Less abundant kaolinite and smectite are also present. With respect to their physicochemical properties, all samples have good thermal properties which make them potentially suitable for therapeutic or aesthetic purposes.

scholarly journals Ceramic raw materials from the State of Maranhão, Brazil. Part 1: chemical and mineralogical characterization and technological properties of clays from São Luis, Rosário, Pinheiro and Mirinzal

2012 ◽  
Vol 65 (4) ◽  
pp. 513-521
Author(s):  
José Manuel Rivas Mercury ◽  
Gricirene Sousa Correia ◽  
Nazaré Socorro Lemos Silva Vasconcelos ◽  
Aluísio Alves Cabral Jr. ◽  
Rômulo Simões Angélica
Keyword(s):  
Raw Materials ◽  
Mineralogical Composition ◽  
Exchange Capacity ◽  
High Plasticity ◽  
X Ray Diffraction ◽  
Specific Mass ◽  
Mineralogical Characterization ◽  
Heat Treated ◽  
Heavy Clay

This work involved the characterization of clays collected in the municipalities of São Luis, Rosário, Pinheiro and Mirinzal (state of Maranhão, Brazil), based on specific mass, specific surface area, cation exchange capacity (CEC), particle size distribution, X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TG-DTA) and Atterberg limits. Technological tests for ceramic applications were also carried out on compacts pressed under 20 MPa and heat-treated at 850, 950, 1050, 1150 and 1250ºC. Our results indicated that two of the clays composed of kaolinite, quartz, and anatase with high plasticity limits, have excellent properties and can be used in the whiteware industry. The other ones are red-firing clays and have a mineralogical composition of quartz, kaolin, feldspar, montmorillonite, hematite and goethite. The latter showed low and moderate values of plasticity, which makes them suitable for the production of heavy clay products.

scholarly journals Modifying admixtures to cement compositions produced from local raw materials

2018 ◽  
Vol 143 ◽  
pp. 02006
Author(s):  
Daria Vasileva ◽  
Egor Protodiakonov ◽  
Anastasia Egorova ◽  
Svetlana Antsupova
Keyword(s):  
Cement Paste ◽  
Raw Materials ◽  
Mineralogical Composition ◽  
Raw Material ◽  
Free Calcium ◽  
Hardened Cement ◽  
X Ray Diffraction ◽  
Hardened Cement Paste ◽  
X Ray ◽  
Insoluble Compounds

Durability of hardened cement paste depends on chemical and mineralogical composition of Portland cement. The main factor for hardened cement paste is higher content of calcium aluminate and free calcium hydroxide, binding of which into water-insoluble compounds causes increase in resistance to water, frost and corrosion. The purpose of this research is to develop modifying admixtures to cement compositions based on local raw material - rock sand. Chemical and mineralogical properties of the source materials were studied using X-ray spectroscopy and X-ray diffraction analysis. Standard methods were used for defining physico-mechanical properties of sand and binder. Influence of the degree of mechanochemical activation of modifying admixture on the properties of binder and hardened cement paste made on its basis was studied. Research methods of scanning electron microscopy and spectral measurements were applied. The possibility of using admixture based on rock sand as a modifier was determined, its usage providing increase of strength, sulphate and frost resistance, which causes higher durability of cement concrete.

scholarly journals Methodological Approach (In Situ and Laboratory) for the Characterisation of Late Prehistoric Rock Paintings—Penedo Gordo (NW Spain)

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 551
Author(s):  
Jose Santiago Pozo-Antonio ◽  
Beatriz Comendador Rey ◽  
Lara Alves Bacelar ◽  
Pablo Barreiro
Keyword(s):  
Raw Materials ◽  
Methodological Approach ◽  
Analytical Techniques ◽  
Mineralogical Composition ◽  
X Ray Diffraction ◽  
Late Neolithic ◽  
Nw Spain ◽  
Analytical Protocol ◽  
Rock Paintings

This paper draws on the study of the prehistoric art site of Penedo Gordo (NW Spain) resulting from a collaborative interdisciplinary research. One of its primary goals was to design and put into practice a multi-analytical protocol for characterising prehistoric rock paintings, combining in situ and laboratory analytical techniques. Thus, following the archaeological assessment of the site, the panels exhibiting red paintings were analysed by colour spectrophotometry and portable Raman spectroscopy. Analytical techniques were applied to a collection of samples exhumed from the excavation that simultaneously took place on site. These included three red accretions on different substrates (compact soil, white quartzite and grey quartzite) and stone fragments representative of the outcrop’s petrographic variability, aiming to determine their mineralogical composition, texture and study the stone-paint boundaries. Moreover, colouring materials exhumed from the excavation and collected in the immediate surroundings of the rock outcrop were analysed in order to scrutinise the provenience rock art’s raw materials. Laboratory analysis consisted of stereomicroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. One of the major outcomes was the discovery of a drop of red pigment preserved in an archaeological layer associated with Late Neolithic/Copper Age material remains.

scholarly journals Analisis Variasi Temperatur Aktivasi Terhadap Struktur Kristalin Arang Aktif Dari Tandan Aren (Arenga Pinnata Merr) Dengan Agen Aktivasi Potassium Silicate (K2SiO3)

2020 ◽  
Vol 5 (4) ◽  
pp. 300
Author(s):  
Nurlia Nurlia ◽  
Muhammad Anas ◽  
Erniwati Erniwati
Keyword(s):  
Activated Carbon ◽  
Crystalline Structure ◽  
Raw Materials ◽  
Chemical Activation ◽  
Weight Ratio ◽  
Potassium Silicate ◽  
Physical Activation ◽  
X Ray Diffraction ◽  
Activation Temperature ◽  
Irregular Arrangement

This study aims to determine the effect of variations of  activation temperature of  activated carbon from sugar palm bunches of chemically activatied with the activation agent of potassium silicate (K2SiO3) on the crystalline structure. Activated carbon is the result of pyrolysis of carbonaceous raw materials at temperatures lower than  of 1000 oC. Activated carbon from bunches of sugar palm acquired in four steps: preparation steps, carbonization steps using the pyrolysis reactor with temperature of 300 oC - 400 oC for 8 hours and chemical activation using of potassium silicate (K2SiO3) activator in weight ratio of 2: 1 and physical activation using the electric furnace for 30 minutes with temperature variation of 600 oC, 650 oC, 700 oC, 750 oC and 800 oC. The crystalline structure tested by X-Ray Diffraction (XRD) method, the results yielded of 26,60o, 26,62o, 26,16o, 26,22o, 26,97o,  and 26,68o respectively. The highest crystalline structure yield was 22.26% at temperature of  600 oC and the lowest was 8.83% at temperature of 650 oC. The results obtained were amorphous  91.17% at the highest temperature of 650 oC and the lowest 77.74% at temperatur of  600 oC  which has a random and irregular arrangement pattern of atoms or molecules repeatedly or not periodically.

scholarly journals CHEMICAL-MINERАLOGICAL CHARACTERIZATION OF BAUXITES FROM DIFFERENT DEPOSITS

2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Gordana Оstojić ◽  
Dragica Lazić ◽  
Branko Škundrić ◽  
Jelena Penavin Škundrić ◽  
Slavica Sladojević ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Raw Materials ◽  
Mineralogical Composition ◽  
Chemical Characteristics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

From the aspect of their chemical and mineralogical composition, bauxites are very complex multicomponent raw materials. The paper presents the characterization of bauxite from several different deposits: Brazil, Milići, Čitluk and Kosovo. Chemical characteristics were determined by a combination of different analytical methods: gravimetry, potentiometric titration, atomic absorption spectroscopy (AAS) and UV-VIS spectrophotometry. Mineralogical composition was determined using X-ray diffraction and thermal analysis methods. Chemical and structural characterization is complemented by the results of scanning electron microscopy with EDX analysis. The information obtained was used for the assessment of the quality of investigated bauxites from the aspect of their application in the production of alumina.

Mechanical Behaviour of MgO-CaZrO3-Based Refractories for Cement Kilns

2010 ◽  
Vol 70 ◽  
pp. 47-52 ◽  
Author(s):  
Carmen Baudín ◽  
Pilar Pena ◽  
Álvaro Obregón ◽  
Jose Luis Rodríguez-Galicia
Keyword(s):  
Mechanical Behaviour ◽  
Phase Distribution ◽  
Raw Materials ◽  
Mineralogical Composition ◽  
Modulus Of Rupture ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
Reflected Light ◽  
Grain Size Distributions ◽  
Equilibrium Relationships

The mechanical behaviour of ceramic refractories formulated in the MgO-CaO-SiO2- ZrO2 system is analysed in terms of the room temperature Young´s modulus, the modulus of rupture and the work of fracture at 25 and 1100°C. The materials have been designed taking into account the phase equilibrium relationships to obtain MgO-CaZrO3-Ca2SiO4-Ca3Mg(SiO4)2 or MgO-CaZrO3-Ca3Mg(SiO4)2-c-ZrO2 as final crystalline phases. Different relationships between the proportion and sizes of the fines and the aggregates have been explored. The microstructure of the materials has been characterised in terms of density, crystalline phases and phase distribution and morphology. A combination of X-Ray diffraction (XRD) analyses and Reflected Light Optical Microscopy (RLOM) has been used. The relationships between the obtained phases and microstructures and the grain size distributions of the used raw materials have been established. The relationships between the mineralogical composition and the obtained microstructure and the mechanical behaviour are discussed.

Reduction of clinkerisation temperature by addition of salts containing fluorine

2006 ◽  
Vol 33 (8) ◽  
pp. 1090-1097 ◽  
Author(s):  
Larbi Kacimi ◽  
Angélique Simon-Masseron ◽  
Abdelhamid Ghomari ◽  
Zoubir Derriche
Keyword(s):  
Setting Time ◽  
Physical And Mechanical Properties ◽  
Specific Area ◽  
Mineralogical Composition ◽  
Optical Microscope ◽  
Strength Properties ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
Burning Temperature ◽  
X Ray

The influence of some salts containing fluorine (CaF2, NaF, and KF) on the reduction of burning temperature of Portland clinker from three Algerian cement factories (units of Zahana, Beni-Saf, Chlef) has been studied in this paper. X-Ray fluorescence, optical microscope technique, and powder X-ray diffraction were then used to characterize each clinker and its raw mixture in terms of chemical composition and clinker mineralogical composition. The effects of these mineralizers on structural and morphological properties of clinker minerals and on the presence of alite were investigated by scanning electron microscopy combined with microprobe analysis. Physical and mechanical properties (density, specific area, setting time, hydration heat, expansion, and mechanical strength) of some samples were studied. The results show that the presence of the mineralizers under study induced a decrease of the burning temperature. For example, NaF improved the crystallization of clinker minerals with high alite rate. These characteristics explain the improvement of physical and strength properties of the new clinkers.Key words: clinker, alite, structure, hydraulic activity, clinkerisation temperature, mineralizer.

scholarly journals EVALUATION OF BIOGENIC LIMESTONES FROM HERETHIANA AREA IN WESTERN CRETE FOR HYDRAULIC LIME PRODUCTION

2004 ◽  
Vol 36 (1) ◽  
pp. 28
Author(s):  
Θ. Μαρκόπουλος ◽  
Γ. Τριανταφύλλου ◽  
Ε. Μανούσογλου
Keyword(s):  
Raw Materials ◽  
X Ray Diffraction ◽  
Silicate Phase ◽  
Free Lime ◽  
Hydraulic Lime ◽  
X Ray ◽  
European Standards ◽  
Main Component ◽  
Lime Production ◽  
Representative Samples

Biogenic limestones from the area of Herethiana, Western Crete, have been examined in order to evaluate their properties as hydraulic lime raw materials. Samples of three different horizons, X1, X2, and X3 have been investigated using X -ray diffraction (XRD), X - ray fluorescence spectroscopy (XRF), optical and scanning electron microscopy (SEM) and calcimetry analyses. According to the XRD analyses the main component is calcite variying between 80% and 84%. Illite, quartz, albite and goethite are also present in minor amounts. Representative samples, with a particular grain size of the different horizons, were burned at 900°C for 12 hours, to produce hydraulic lime. The analysis of the calcined products showed that larnite, portlandite and lime appear in all samples. Quartz and hematite are also present in minor amounts. The abundance of amorphous silica in the form of silica sponges and diatoms offers the necessary active silica to form, together with an appropriate portion of free lime, the calcium-silicate phase, which is present in all samples in adequate percentages. According to the European standards of the building limes the calcined products of the materials of the three different horizons can be classified as feebly, moderate and eminently hydraulic limes

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