mineralogical compositions
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2022 ◽  
Vol 1049 ◽  
pp. 266-272
Author(s):  
Inomjon Tojiev

The article covers the research of the chemical and mineralogical compositions of mortars used in the construction of architectural monuments of Uzbekistan in the 9th-12th centuries, which is based on the study of chemical composition, X-ray and differential thermal analyzes. Comprehensive study of the building materials used in mentioned monuments will allow development of identical modified solutions to preserve the value of architectural monuments.


Author(s):  
Hoc Thang Nguyen ◽  
Quang Minh Do

Red mud (RM) is an industrial waste obtained from the Bayer process which is usually discharged into marine or disposed into a landfill causing pollution for the surrounding water, air, and soils. Thus, disposal of RM is an environmental concern, and it should be recycled effectively. Because RM consists of iron- and aluminum-rich phases, it is possible to be processed into cementitious material and utilized for construction purposes. This research fabricated a type of cement from the mixture of RM and limestone. The mixture was sintered at temperature of 1180 °C to obtain the clinker of the novel hydraulic cement with C2S, C3A, and C4AF minerals. In which, C2S, C3A, and C4AF are respectively belite, alite, and tetra-calcium aluminoferrite compounds that are characteristic hydraulic minerals of Portland cement clinker. The specifications of this cement were tested and evaluated in this study such as chemical and mineralogical compositions, fineness, specific surface area, mechanical strength after 3, 7, and 28 days.


2021 ◽  
Vol 10 (17) ◽  
pp. e169101724828
Author(s):  
Gabriel Octávio de Mello Cunha ◽  
Jaime Antonio de Almeida

Detailed knowledge of chemical, petrographic and mineralogical compositions as well as the effects of applying rock powder on soil chemical properties and plant production are required for classifying these materials as soil remineralizers (SR), as according to Brazilian legislation in force. This study aimed to evaluate the potential of rock powders siltstone, tephrite and olivine melilitite, pure or mixed, on improving the fertility of a Cambisol and a Nitisol as well as the yield of soybean and barley crops grown in succession inside a greenhouse. For that purpose, these products were characterized as their granulometry, chemical, mineralogical and petrographic compositions. Based on the results, it was verified which products met the requirements for registration as SR established by the Normative Instruction Number 5 (NI5) from MAPA. Elemental chemical and grain size analyses indicated that all tested products met the NI5 requirements for their registration as SR. The mineral composition identified through petrographic analyses was confirmed by analyses performed via X-ray diffractometry techniques. Olivine melilitite rock, pure or mixed with siltstone, had the highest agronomic potential when compared to other powders, thus acknowledged as a SR. Although tephrite had little agronomic response on evaluated soils and crops, it also meets the SR requirements. Siltstone fulfilled most of NI5 criteria, except for exceeding the maximum content of free silica (quartz); therefore, it likely does not meet the requirements for its admittance as a SR.


2021 ◽  
pp. 1-29
Author(s):  
Sanghamitra Bharati ◽  
Manjini Sambandam ◽  
Pankaj Lochan

Strict environmental norms and raising concern to recycle solid wastes generated during ironmaking and steelmaking processes has been the key driving force in developing various technologies. The present study describes a calcium-aluminate clinker prepared from steel ladle slag by modifying its mineral compositions. The slag paste prepared by mixing with water exhibited flash setting behaviour due to the presence of C12A7 and C3A phases. In contrast, the slag clinker, developed by sintering a mixture of pre-determined quantity of slag and Al2O3 at 1400°C for 2h and 4h, contained CA, CA2, Gehlenite and ‘Q’ phases. Hydration of slag clinker contained stable C3AH6, AH3 and stratlingite with preferential growth of calcium-aluminate hydrate prisms along c-axis that provided a well-defined raceme like morphology with interlinked structure. It improved the setting time and crushing strength of the clinkers after 6h and 24h curing at room temperature. Additionally, presence of ‘Q’ phase with lamellar prismatic crystals also helped in enhancing the strength. The developed clinker also exhibited superior crushing strength as compared to commercially available calcium aluminate cement of medium purity. The slag, used as a source of CaO could replace CaCO3 completely and thus contributed to reduction in CO2 emission during clinker making process.


2021 ◽  
Author(s):  
Mahmoud Mohamed Ibrahim ◽  
Stephen Andrew Bowden

Abstract Grainstones deposited on carbonate ramps are excellent petroleum reservoir formations and are important for energy needs. Waterflooding is routinely used to augment oil recovery and many carbonate fields have long production histories. Future management of these "mature" assets requires knowledge of how oil production can be sustained and enhanced but requires understanding the pore-scale displacement processes. Despite decades of waterflooding in carbonate oilfields a plausible displacement efficiency prediction is not yet trivial. To evaluate waterflooding economics, it is crucial to know the residual oil saturation (Sor) and where oil is entrapped by capillarity in the reservoir. Microfluidic waterflooding experiments provide a means to visualize pore-scale phenomena within different carbonate minerals (calcite, dolomite, and gypsum) and petrographic textures, to estimate microscopic displacement efficiency. By using analogues of carbonate ramp reservoir-lithologies (in terms of texture, unstructured-irregular pore networks and varied mineralogical compositions) realistic evaluations of displacement efficiency were determined for different mineralogical compositions. The quantitative test results matched closely Arab formation SCAL published data. It was determined that multi-mineralic grainstones undergoing waterflood likely experience contemporaneous imbibition and drainage, giving rise to complex multiphase flow due to the existence of different states of wettability. This wettability contrast induces "capillary jumps" across wettability-boundaries at the interface between different lamina or textures. These "capillary leaps" account for increase in oil recovery as they occur but leave behind bypassed oil. Consequently poly-mineralic arrangements have a lower oil recovery compared to mono-mineralic cases. It was observed that distinct Sor are achieved at different injected pore volumes, despite sharing similar porosity & permeability, thus the relationship between Sor and porosity/permeability is weak. Thus, predicting waterflooding efficiency requires the different carbonate minerals Sor to be incorporated in dynamic simulation.


2021 ◽  
pp. 103770
Author(s):  
Túllio Alexandre Mustafé da Cruz ◽  
Rodrigo Henrique Geraldo ◽  
Ana Rita Damasceno Costa ◽  
Kuelson Rândello Dantas Maciel ◽  
Jardel Pereira Gonçalves ◽  
...  

Minerals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1316
Author(s):  
Cindy Cindy ◽  
Ryotaro Sakai ◽  
Diego M. Mendoza ◽  
Kojo T. Konadu ◽  
Keiko Sasaki

Environmentally friendly pretreatment of double refractory gold ores (DRGO) to improve gold recovery without emitting pollutant gas is challenging. Sequential biotreatment, including iron-oxidizing microorganisms to decompose sulfides, followed by the enzymatic decomposition of carbonaceous matter, was recently developed. The effect of acid washing by 1 M HCl for 24 h between two bioprocesses was evaluated using a real double refractory gold ore from the Syama mines, Mali, which includes 24 g/t of Au and 5.27 wt % of carbon with a relatively higher graphitic degree. The addition of the acid washing process significantly improved gold recovery by cyanidation to yield to 84.9 ± 0.7% from 64.4 ± 9.2% (n = 2). The positive effects of acid washing can be explained by chemical alteration of carbonaceous matter to facilitate the accessibility for lignin peroxidase (LiP) and manganese peroxidase (MnP) in cell-free spent medium (CFSM), although the agglomeration was enhanced by an acid attack to structural Fe(III) in clay minerals. Sequential treatment of DRGO basically consists of the oxidative dissolution of sulfides and the degradation of carbonaceous matter prior to the extraction of gold; however, the details should be modified depending on the elemental and mineralogical compositions and the graphitic degree of carbonaceous matter.


2021 ◽  
Vol 882 (1) ◽  
pp. 012020
Author(s):  
I Setiawan

Abstract Indonesia needs a proven technology for REE extraction to build a national REE industry. Monazite that has been recovered from placer deposits at Bangka-Belitung areas is the most potential REE source. In the future, ion adsorption type will be another potential source of REE deposits. This paper describes the sequential REE extraction of the weathered crusts of granitoids from Sibolga using sequential extraction ICP-MS analysis is applied to determine bulk samples mineralogical compositions and REE content. The total REE (∑REE) content of weathered crusts of granitoids from Sibuluhan Sihaporas A ranges from 265 to 479 ppm, while the amount of ∑REE leached by sequential extraction range from 151 to 263 ppm, and the percentage of adsorbed ∑REE ranges from 55 to 74%. In comparison, Sibuluhan Sihaporas B ranges from 302 to 634 ppm, 82 to 198 ppm, and 28 to 44%, respectively. ∑REE content of weathered granitoids crusts from Sarudik ranges from 135 to 219 ppm, while that SREE leached by sequential extraction range from 21 to 82 ppm, and percentage of adsorbed ∑REE range from 11 to 50 %, while that Sibolga Julu ranges from 191 to 304 ppm, 111 to 138 ppm, and 27 to 44%.


Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 766
Author(s):  
Uxue Sanchez-Garmendia ◽  
Javier G. Iñañez ◽  
Gorka Arana

Ancient ceramics recovered after a long burial period have probably undergone several alterations and contaminations, introducing a chemical variability, affecting the ceramic’s natural variability. That is, the chemical and the mineralogical compositions of the ceramic pastes after their deposition will not be the same as they originally were. Therefore, it is known that the alteration and contamination processes, and the discrimination of some elements, should be considered when studying the ceramics to avoid incorrect interpretations about their provenance, technology and the use of the artefact, as well as its proper preservation. In the present work, the authors performed an experimental approach in order to study the alterations and contaminations that occurred in 60 ceramic cylinders buried in two different underwater environments. Once the pieces were taken out from the water environments, they were characterized by a multi-analytical approach. For this purpose, inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffraction (XRD), scanning electron microscopy–energy dispersive spectrometry (SEM–EDS) and Raman spectroscopy were used. Newly formed minerals of different forms have been identified, with different crystallization grades. Some examples are the needles, flakes, sponges and long and short prisms composed of several elements such as Ca, F, S and O.


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