Microanalytical studies (X-ray photoelectron spectrometry) of surface hydration reactions of cement compounds

1983 ◽  
Vol 310 (1511) ◽  
pp. 85-92 ◽  
Keyword(s):  
Blast Furnace ◽  
Chemical Composition ◽  
Kinetic Energy ◽  
Blast Furnace Slag ◽  
X Rays ◽  
Hydration Time ◽  
X Ray ◽  
Tentative Interpretation ◽  
Furnace Slag ◽  
Cement Compounds

X-ray photoelectron spectrometry (X.p.s.) measures the kinetic energy of electrons photoejected from a solid surface by soft X-rays. The kinetic energy of the photoelectrons can be related to the binding energy that these electrons had originally in the solid. X.p.s. is a rather new technique for studying cements. It has been used recently in the surface analysis of C 3 S, C 2 S, C 3 A and blast-furnace slag grains during their hydration. Changes in chemical composition have been found as soon as the surface comes into contact with water, shown by a change in the shape, position an intensity of characteristic peaks like Ca 2p , Si 2p , O l8 and a reduction of characteristic ratios Ca/Si or Al/Si. A tentative interpretation of X.p.s. kinetic curves as a function of hydration time is presented.

Adsorption of Phosphate from Aqueous Solution with Blast Furnace Slag Activated by Hydrated Lime as Sorbent

2009 ◽  
Vol 620-622 ◽  
pp. 643-646
Author(s):  
Lin Bo Li ◽  
Jun Zhu ◽  
Qi Wang ◽  
Jun Yang
Keyword(s):  
Aqueous Solution ◽  
Blast Furnace ◽  
Chemical Composition ◽  
Blast Furnace Slag ◽  
Orthogonal Experiment ◽  
Weight Ratio ◽  
Absorption Spectrometry ◽  
Hydrated Lime ◽  
Hydration Time ◽  
Furnace Slag

This paper describes a method of removing phosphate (P) from aqueous solution by sorbent prepared with amorphous blast furnace slag (BFS) and hydrated lime. An orthogonal experiment was carried out to investigate the factors of hydration time, slurrying temperature and the weight ratio of blast furnace slag /hydrated lime and water/solid on the reactivity of the sorbent. Chemical composition of BFS was analyzed by atomic absorption spectrometry, microstructure and phase analysis of samples were conducted by SEM and XRD. It is found that all sorbents prepared show higher P adsorption capacity than single blast furnace slag.

Modeling of Alteration Behavior on Blended Cementitious Materials

2011 ◽  
Author(s):  
Hitoshi Owada ◽  
Tomoko Ishii ◽  
Mayumi Takazawa ◽  
Hiroyasu Kato ◽  
Hiroyuki Sakamoto ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Fly Ash ◽  
Chemical Composition ◽  
Mineral Composition ◽  
Blast Furnace Slag ◽  
Fine Powder ◽  
Cementitious Materials ◽  
Leaching Tests ◽  
Measured Concentration ◽  
Furnace Slag

A “realistic alteration model” is needed for various cementitious materials. Hypothetical settings of mineral composition calculated based on the chemical composition of cement, such as Atkins’s model, have been used to estimate the alteration of cementitious material. However, model estimates for the concentration of certain elements such as Al and S in leachate have been different from experimental values. In a previous study, we created settings for a mineralogical alteration model by taking the initial chemical composition of cementitious materials from analysis results in experiments and applying their ratios to certain hydrated cement minerals, then added settings for secondary generated minerals in order to account for Ca leaching. This study of alteration estimates for ordinary portland cement (OPC) in groundwater showed that the change in Al and S concentrations in simulated leachate approached values for actual leachate[1]. In the present study, we develop an appropriate mineral alteration model for blended cementitious materials and conduct batch-type leaching experiments that use crushed samples of blast furnace slag cement (BFSC), silica cement (SC), and fly ash cement (FAC). The cement blends in these experiments used OPC blended with blast furnace slag of 70 wt.%, silica cement consisting of an amorphous silica fine powder of 20 wt.%, and fly ash of 30 wt.%. De-ionized water was used as the leaching solution. The solid-liquid ratios in the leaching tests were varied in order to simulate the alteration process of cement hydrates. The compositions of leachate and minerals obtained from leaching tests were compared with those obtained from models using hypothetical settings of mineral composition. We also consider an alteration model that corresponds to the diversity of these materials. As a result of applying the conventional OPC model to blended cementitious materials, the estimated Al concentration in the aqueous solution was significantly different from the measured concentration. We therefore propose an improved model that takes better account of Al behavior by using a more reliable initial mineral model for Al concentration in the solution.

scholarly journals PROPERTIES OF CONCRETE USING BLAST-FURNACE SLAG CEMENT TYPE A WITH MODIFIED CHEMICAL COMPOSITION

2010 ◽  
Vol 64 (1) ◽  
pp. 244-250 ◽  
Author(s):  
Shingo MIYAZAWA ◽  
Takashi YOKOMURO ◽  
Hiromi FUJIWARA ◽  
Kiyoshi KOIBUCHI
Keyword(s):  
Blast Furnace ◽  
Chemical Composition ◽  
Blast Furnace Slag ◽  
Type A ◽  
Cement Type ◽  
Slag Cement ◽  
Furnace Slag

scholarly journals The Effects of Temperature on the Hydrothermal Synthesis of Hydroxyapatite-Zeolite Using Blast Furnace Slag

Materials ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2131 ◽  
Author(s):  
G.U. Ryu ◽  
G.M. Kim ◽  
Hammad R. Khalid ◽  
H.K. Lee
Keyword(s):  
Blast Furnace ◽  
Hydrothermal Synthesis ◽  
Blast Furnace Slag ◽  
Raw Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Type Zeolite ◽  
Effects Of Temperature ◽  
Furnace Slag

Blast furnace slag, an industrial by-product, is emerging as a potential raw material to synthesize hydroxyapatite and zeolite. In this study, the effects of temperature on the hydrothermal synthesis of hydroxyapatite-zeolite from blast furnace slag were investigated. Specimens were synthesized at different temperatures (room temperature, 50, 90, 120, or 150 °C). The synthesized specimens were analyzed qualitatively and quantitatively via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), BET/BJH, and scanning electron microscopy/energy dispersive using X-ray analysis (SEM/EDX). It was found that the hydroxyapatite phase was synthesized at all the reaction temperatures, while faujasite type zeolite appeared in the specimens synthesized at 90 and 120 °C. Moreover, faujasite was replaced by hydroxysodalite in the specimens synthesized at 150 °C. Additionally, the crystals of the hydroxyapatite tended to become larger and total crystallinity increased as the reaction temperature increased.

Development and Characterization of Cementing Composites with Blast Furnace Slag Replacement

2014 ◽  
Vol 976 ◽  
pp. 246-250
Author(s):  
Reyna Sánchez-Ramírez ◽  
Manuela Diaz-Cruz ◽  
Sebastían Díaz de La Torre ◽  
Enrique Rocha-Rangel
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Bending Strength ◽  
Isothermal Calorimetry ◽  
Oil Wells ◽  
X Ray Diffraction ◽  
Hydration Kinetics ◽  
X Ray ◽  
Furnace Slag

In this work, they were produced and characterized cementing composites made with blast furnace slag replacement, for their use in the construction of oil wells. To this, slurries were prepared with a replacement of 20 and 30% slag, as well as a slurry with 100 % slag and a slurry with 100% H-cement were prepared. Starting materials were characterized by chemical analysis, X-ray diffraction and Fourier Transformed Infra Red. Slurries also were activated with sodium silicate in order to study theirs hydration kinetics, driving by isothermal calorimetry. These studies were complemented by the preparation of specimens of 4 X 4 X 16 cm to which they determine its compressive and bending strength during 2 and 28 days of curing. From the results it can be concluded that it was obtained a product that can be effectively used in the construction of oil wells.

Investigation of Gamma Radiation Shielding of Concrete Containing Blast Furnace Slag Waste via Experimental and Calculation Methods

2018 ◽  
Vol 765 ◽  
pp. 329-334 ◽  
Author(s):  
Pranpriya Phutthanet ◽  
Pithiwat Tiantong ◽  
Phongthorn Julphunthong ◽  
Panuwat Joyklad ◽  
Li Jie Wang ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Chemical Composition ◽  
Attenuation Coefficient ◽  
Blast Furnace Slag ◽  
Radiation Shielding ◽  
Linear Attenuation Coefficient ◽  
Fine Aggregate ◽  
Study Results ◽  
Shielding Properties ◽  
Furnace Slag

This study aims to evaluate gamma-ray shielding characteristics of concrete produced from blast furnace slag. The chemical and physical properties of the aggregates including the chemical composition and specific gravity were investigated to evaluate their radiation shielding properties. The samples were prepared with a cement content of 400 kg/m3, a water to cement ratio of 0.4, and fine aggregate of 43% and coarse aggregate ratio of 57%. Blast furnace slag was replaced with sand at 25%, 50%, 75% and 100% by volume to improve the shielding properties. The compressive strengths at 3, 7 and 28 days and the unit weight of the prepared samples were determined. The linear attenuation coefficient was measured and calculated at photon energies of 0.662 MeV, 1.17 MeV and 1.33 MeV. The WinXCom program was employed to calculate the attenuation coefficient from the chemical composition of samples and the results were compared to the measured results. The study results suggest that the use of blast furnace slag is effectively in improving the compressive strength and shielding properties of concrete. The increase of blast furnace slag caused an increase in the linear attenuation from 0.190 cm-1 to 0.210 cm-1 at 0.662 MeV.

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