Behaviour of Cement CEM III / B under Acid Solutions Agression (I)

2008 ◽  
Vol 59 (6) ◽  
Author(s):  
Ion Teoreanu ◽  
Alice Pop2 ◽  
Mariana Coarna ◽  
Daniela Natac
Keyword(s):  
Compressive Strength ◽  
Chemical Composition ◽  
Phosphoric Acid ◽  
Acid Solution ◽  
Acid Corrosion ◽  
Point Of View ◽  
Acid Solutions ◽  
X Ray Diffraction ◽  
Cement Pastes ◽  
X Ray

This paper aims at investigating the behaviour of a type CEM III/B cement under acid corrosion with formation of insoluble products. Cement paste and mortar specimens have been cured in sulphuric acid and phosphoric acid solutions. The samples have been kept in water up to 28 days and further 180 days in 0.5 mol/L acid solutions. At specific terms, the samples underwent compressive strength, chemical and X-ray diffraction analysis. The tests� results pointed out significant differences of chemical composition between the corrosion layers and the uncorroded core. The corrosion products formed in each acid solution were identified. In concretes with composite, ecologic cements the corrosion noticed on the cement pastes can be avoided. For that purpose during the preparation of the concretes there have to be achieved a high compactness and, consequently, a high impermeability. The binder matrix of the concrete is therefore, performing from the point of view of the resistance against the acid corrosion.

scholarly journals Characteristics and Design of Inong Balee Fort Binding Mortar For Restoration Purposes

Elkawnie ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 302
Author(s):  
Muttaqin Hasan ◽  
Teuku Budi Aulia ◽  
Fido Yurnalis
Keyword(s):  
Compressive Strength ◽  
Chemical Composition ◽  
Diffraction Pattern ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Indonesian Government ◽  
Powder Samples

Abstract: Inong Balee Fort is one of the Islamic Kingdom of Aceh heritage built in 1599 by Admiral Malahayati but several parts of the fortress wall have currently been damaged and the stone removed. Indonesian Government plans to restore the fort and this makes it necessary to examine the characteristics of the fortress mortar with a focus on the chemical composition and mineralogical elements. Therefore, mortar powder samples obtained from the fort walls were tested through X-Ray Diffraction (XRD) and the results showed the main composition of mortar is CaCO3 and SiO2 from a mixture of lime and sand while the others are P2O5, MgCO3, and Al2O3. Meanwhile, two mortar mixtures including 1 lime: 2 sand and 1 cement: 2 lime: 3 sand were designed for restoration purposes and they were both found by the XRD analysis results to have a diffraction pattern similar to Inong Balee Fort mortar. However, mortar with 1 lime: 2 sand has a very low compressive strength subsequently it does not meet the specifications of the SNI 6882:2014 and ASTM C270-19a while mortar with 1 cement: 2 lime: 3 sand has a compressive strength that meets the specifications. Therefore, a mortar with 1 cement: 2 lime: 3 sand is recommended to be used for the restoration of Inong Balee Fort.Abstrak: Benteng Inong Balee merupakan salah satu peninggalan Kerajaan Islam Aceh yang dibangun pada tahun 1599 oleh Laksamana Malahayati. Saat ini banyak bagian dinding pasangan batu benteng tersebut sudah rusak dan batunya sudah terlepas dari ikatan mortar. Pemerintah Republik Indonesia berencana melakukan restorasi benteng tersebut. Oleh karena itu perlu diteliti karakteristik mortar pengikat dari pasangan batu benteng tersebut, berupa kandungan senyawa kimia dan mineralnya. Metode yang digunakan untuk karakterisasi adalah dengan melakukan pengujian X-Ray Diffraction (XRD) terhadap bubuk sampel mortar yang diambil dari dinding benteng. Hasil pengujian menunjukkan bahwa komposisi utama mortar pengikatnya adalah CaCO3 dan SiO2 yang menunjukkan bahwa mortar tersebut terbuat dari campuran kapur dan pasir. Disamping itu juga terdapat kandungan senyawa P2O5, MgCO3 dan Al2O3. Selanjutnya untuk keperluan restorasi didesain 2 campuran mortar, yaitu mortar dengan campuran 1 kapur : 2 pasir dan mortar dengan campuran 1 semen : 2 kapur : 3 pasir. Hasil analisis XRD menunjukkan bahwa kedua campuran tersebut mempunyai pola diffraksi yang mirip dengan Benteng Inong Balee. Akan tetapi mortar dengan campuran 1 kapur : 2 pasir mempunyai kuat tekan yang sangat rendah sehingga tidak memenuhi spesifikasi Standar SNI 6882:2014 dan ASTM C270-19a, sedangkan mortar dengan campuran 1 semen : 2 kapur : 3 pasir mempunyai kuat tekan yang memenuhi spesifikasi Standar SNI 6882:2014 dan ASTM C270-19a, sehingga mortar ini disarankan digunakan untuk keperluan restorasi Benteng Inong Balee.

scholarly journals Research on fabricartion of non-calcined geopolymer ceramics from kaolin Tung Ba, Vi Xuyen, Ha Giang

2019 ◽  
Vol 41 (4) ◽  
pp. 388-402
Author(s):  
Tran Thi Lan ◽  
Nguyen Anh Duong ◽  
Phan Luu Anh ◽  
Tran Thi Man
Keyword(s):  
Compressive Strength ◽  
Chemical Composition ◽  
Water Absorption ◽  
Heating Time ◽  
Kaolin Clay ◽  
Mineral Component ◽  
Optimal Parameters ◽  
X Ray Diffraction ◽  
X Ray

The mineral component of kaolin clay in Tung Ba commune analyzed by X-ray diffraction is composed mainly of kaolinite (24–27%), illite (26–30%) and quartz (40–44%). Chemical composition (wt%) of Tung Ba kaolin determined by X-ray fluorescence (XRF) shows SiO2 at 59.92–64.98, Al2O3: 18.95–20.82, Fe2O3: 2.28–3.95, SO3: 2.47–4.66, CaO: 0.12–0.36, MgO: 1.72–2.13 and TiO2 at 0.75–1,08. To fabricate geopolymer ceramic, kaolin clay was transformed into metakaolin with the optimal parameters of calcination: the temperature at 750°C and heating time of 120 min. Obtained metakaolin is mixed with mixtures of NaOH/Na2SiO3 (40%wt) with ratios of 0.2, 0.25, 0.33, 0.5 and NaOH molarities are 10M, 12M, 14M. Testing geopolymer ceramics after 28 days had a compressive strength of 40–196 KG/cm2, water absorption of 15.25–17.98% and density of 1.54–1.69 g/cm3, totally satisfied the Vietnamese standard for construction bricks and ceramics.

scholarly journals Physical properties and hydration evolution of dispersant containing calcium aluminate cement compositions for endodontic applications

Cerâmica ◽  
2014 ◽  
Vol 60 (355) ◽  
pp. 366-370 ◽  
Author(s):  
A. P. Luz ◽  
V. C. Pandolfelli
Keyword(s):  
Compressive Strength ◽  
Physical Properties ◽  
Calcium Aluminate ◽  
Dimensional Change ◽  
Calcium Aluminate Cement ◽  
X Ray Diffraction ◽  
Cement Pastes ◽  
X Ray ◽  
Polymeric Dispersant ◽  
Aluminate Cement

The purpose of this study was to evaluate the physical properties and hydration evolution of calcium aluminate cement (CAC) compositions containing an advanced dispersant. The compressive strength, dimensional change, apparent porosity and quantitative X ray diffraction analysis (XRD) of the cement pastes were carried out over 1-15 days of curing (with the samples immersed in distilled water) at 37 ºC. The addition of a polymeric dispersant to the selected CAC (Secar 71) resulted in higher, but suitable expansion of the cement samples, and improved uniaxial compressive strength reaching values in the range of 73-87 MPa after 15 days. Quantitative XRD results also showed that C3AH6 and Al(OH)3 were the main phases detected during the cement hydration process, but CAH10 and C2AH8 were also found due to the higher water availability in the curing environment. According to the attained results, it could be concluded that the dispersant containing calcium aluminate cement compositions have the potential to be used as endodontic materials.

In situ x-ray diffraction investigation on early stages of oxidation at 900 °C of γ-TiAl dipped in a phosphoric acid solution

2009 ◽  
Vol 106 (10) ◽  
pp. 103502 ◽  
Author(s):  
S. Y. Brou ◽  
P. O. Renault ◽  
C. Huvier ◽  
J. L. Grosseau-Poussard ◽  
G. Bonnet
Keyword(s):  
Phosphoric Acid ◽  
Acid Solution ◽  
Phosphoric Acid Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Early Stages

scholarly journals Influence of the reaction time during the treatment of bacterial cellulose with sulfuric acid solution

2019 ◽  
Vol 9 (5) ◽  
pp. 4301-4304 ◽  
Keyword(s):  
Sulfuric Acid ◽  
Reaction Time ◽  
Acid Solution ◽  
Bacterial Cellulose ◽  
Sulfuric Acid Solution ◽  
Crystallinity Index ◽  
Acid Solutions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sulfuric Acid Solutions

Biomaterials are one of the most important parts of the medical device industry. Being used frequently in the development of Scaffolds for the tecidual regeneration. Bacterial cellulose is a biomaterial widely used in tissue regeneration. Due to its high content of hydrogen bonds, its crystallinity is high and its solubility is low, which makes its use difficult. Studies carried out with anteriority showed the modification suffered by bacterial cellulose treated with sulfuric acid solutions. The objective of this work was to study the influence of reaction time on crystallinity in the treatment of bacterial cellulose with sulfuric acid solution. Bacterial cellulose was modified by acid hydrolysis with sulfuric acid solutions of 48 or 64% for 60, 120 and 240 min. In all cases, the hydrolysed cellulose was washed with distilled water until pH 7, subsequently the cellulose was washed with ethanol and dried in an oven at 37 ° C until a constant mass. The samples obtained were characterized by X-ray diffraction and the crystallinity index, the apparent crystallite size, the crystallite inner chains and the Z-discriminant function were determined. The results showed that the reaction time has a statistically significant influence on the crystallinity of bacterial cellulose.

Properties of Mortar with Recycled-Cement

2012 ◽  
Vol 193-194 ◽  
pp. 397-401
Author(s):  
Hong Zheng Lu ◽  
Hong Mei Ai ◽  
Fang Yan ◽  
Li Dong Han
Keyword(s):  
Mechanical Property ◽  
Compressive Strength ◽  
Chemical Composition ◽  
Cement Mortar ◽  
Cement Clinker ◽  
Strength Development ◽  
X Ray Diffraction ◽  
X Ray ◽  
Strength Grade ◽  
Waste Concrete

Waste concrete as the main object of the study, was proved to be capable of producing recycled-cement. The chemical composition of recycled-cement was analyzed by X-ray diffraction and compared with industrial clinker from Onoda Company. The result of comparison showed that the minerals in recycled-cement were almost the same as the industrial clinker, except a little MgO and CA. The amount of four main minerals in cement clinker was reasonable. The mechanical property of mortar produced with recycled-cement was measured. The results showed that the compressive strength of recycled-cement mortar can reach the standard of mortar with P.O 32.5. The excess MgO and the strength grade of waste concrete we used in the research were identified as the restriction of the strength development of recycled-cement.

Infrared spectroscopic study of the YPO4-YCrO4 system

1985 ◽  
Vol 50 (10) ◽  
pp. 2139-2145
Author(s):  
Alexander Muck ◽  
Eva Šantavá ◽  
Bohumil Hájek
Keyword(s):  
Spectroscopic Study ◽  
Infrared Spectra ◽  
Point Of View ◽  
Mixed Crystals ◽  
Crystal Symmetry ◽  
Infrared Spectroscopic Study ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared Spectroscopic ◽  
Diffraction Patterns

The infrared spectra and powder X-ray diffraction patterns of polycrystalline YPO4-YCrO4 samples are studied from the point of view of their crystal symmetry. Mixed crystals of the D4h19 symmetry are formed over the region of 0-30 mol.% YPO4 in YCrO4. The Td → D2d → D2 or C2v(GS eff) correlation is appropriate for both PO43- and CrO43- anions.

scholarly journals ZnOTe Compounds Grown by DC-Magnetron Co-Sputtering

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 570
Author(s):  
Olga Sánchez ◽  
Manuel Hernández-Vélez
Keyword(s):  
Molar Fraction ◽  
Variable Parameter ◽  
Point Of View ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sample Series ◽  
Solid Phases ◽  
The One ◽  
High Bulk ◽  
Substrate Sample

ZnOTe compounds were grown by DC magnetron cosputtering from pure Tellurium (Te) and Zinc (Zn) cathodes in O2/Ar atmosphere. The applied power on the Zn target was constant equal to 100 W, while the one applied on the Te target took two values, i.e., 5 W and 10 W. Thus, two sample series were obtained in which the variable parameter was the distance from the Te targets to the substrate. Sample compositions were determined by Rutherford Backscattering Spectroscopy (RBS) experiments. Structural analysis was done using X-Ray diffraction (XRD) spectrometry and the growth of the hexagonal w-ZnO phase was identified in the XRD spectra. RBS results showed high bulk homogeneity of the samples forming ZnOTe alloys, with variable Te molar fraction (MF) ranging from 0.48–0.6% and from 1.9–3.1% for the sample series obtained at 5 W and 10 W, respectively. The results reflect great differences between the two sample series, particularly from the structural and optical point of view. These experiments point to the possibility of Te doping ZnO with the permanence of intrinsic defects, as well as the possibility of the formation of other Te solid phases when its content increases. The results and appreciable variations in the band gap transitions were detected from Photoluminescence (PL) measurements.

Effect of P2O5 on the Properties of Alite-Calcium Strontium Sulphoaluminate Cement

2011 ◽  
Vol 306-307 ◽  
pp. 961-965
Author(s):  
Chao Nan Yin ◽  
Ling Chao Lu ◽  
Shou De Wang
Keyword(s):  
Compressive Strength ◽  
Electron Microscope ◽  
Heat Evolution ◽  
Petrographic Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sulphoaluminate Cement ◽  
Suitable Amount ◽  
Acceleration Period ◽  
Scanning Electron

The influence of P2O5on the properties of alite-calcium strontium sulphoaluminate cement was researched by means of X-ray diffraction, scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) and petrographic analysis. The results show that the optimal content of P2O5is 0.3% and the compressive strength of the cement at 1, 3, 28d are 27.0, 59.1, 110.9MPa when the calcining temperature is 1350°C. P2O5mainly exists in the belite and a suitable amount of P2O5can promote the formation of C1.5Sr2.5A3and alite. When the content of P2O5is higher than 0.3%, the formation of C1.5Sr2.5A3and alite can be hindered. P2O5can enhance the hydration heat evolution rate in the acceleration period and the hydrate heat of cement containing P2O5increases slightly.

scholarly journals Mineralogical stabilization of Ternesite in Belite Sulfo-Aluminate Clinker elaborated from limestone, shale and phosphogypsum

2018 ◽  
Vol 149 ◽  
pp. 01073
Author(s):  
K. Ben Addi ◽  
A. Diouri ◽  
N. Khachani ◽  
A. Boukhari
Keyword(s):  
Infrared Spectroscopy ◽  
Phosphoric Acid ◽  
Portland Cement ◽  
Stability Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Stability

This paper investigates the mineralogical evolution of sulfoaluminate clinker elaborated from moroccan prime materials limestone, shale and phosphogypsum as a byproduct from phosphoric acid factories. The advantage of the production of this type of clinker is related to the low clinkerisation temperature which is known around 1250°C, and to less consumption quantity of limestone thus enabling less CO2 emissions during the decarbonation process compared to that of Portland cement. In this study we determine the stability conditions of belite sulfoaluminate clinker containing belite (C2S) ye’elimite (C4A3$) and ternesite (C5S2$). The hydration compounds of this clinker are also investigated. The monitoring of the synthesized and hydrated phases is performed by X-Ray Diffraction and Infrared spectroscopy. The results show the formation of ternesite at 800°C and the stabilization of clinker containing y’elminite, belite and ternesite at temperatures between 1100 and 1250°C.

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