scholarly journals Pilot production of steel slag masonry blocks

2018 ◽  
Vol 45 (7) ◽  
pp. 537-546 ◽  
Author(s):  
Mehrdad Mahoutian ◽  
Omar Chaallal ◽  
Yixin Shao
Keyword(s):  
Carbon Dioxide ◽  
Steel Slag ◽  
Strength Development ◽  
Carbon Uptake ◽  
X Ray Diffraction ◽  
Calcium Carbonates ◽  
Full Size ◽  
X Ray ◽  
Carbon Dioxide Utilization ◽  
Derivative Thermogravimetry

Masonry blocks are usually made of Portland cement and cured by steam. This study explores the possibility of making masonry blocks using steel slag as binder and carbon dioxide as curing activator. By carbonation activation of steel slag blocks, carbon dioxide can be permanently sequestered in steel slag as calcium carbonates, leading to stronger and more durable construction blocks. In this paper, carbonated steel slag paste was first evaluated by thermogravimetry, derivative thermogravimetry, X-ray diffraction, carbon uptake, strength development, and leaching tests. Based on the preliminary results, the full-size masonry blocks were fabricated using steel slag as the binder and granite as the aggregates. The physical properties and durability of full-size steel slag masonry blocks were then examined through their density, water absorption, moisture content, compressive strength, and fire resistance. An economic analysis was performed and a carbon dioxide utilization capacity was estimated. This study demonstrates that production of steel slag masonry blocks by carbonation is an economically feasible way to utilize carbon dioxide.

Nano-Folded Gold Electrocatalysts Enhance the Selectivity of Carbon Dioxide Reduction

2019 ◽  
Author(s):  
Kam Sang Kwok ◽  
Yuxuan Wang ◽  
Michael Cao ◽  
Hao Shen ◽  
Weinan Xu ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Mass Transport ◽  
Gold Film ◽  
X Ray Diffraction ◽  
Thin Gold Film ◽  
Faradaic Efficiency ◽  
X Ray ◽  
Transmission Electron ◽  
Carbon Monoxide Formation ◽  
Catalytic Interfaces

<p>The local structure and geometry of catalytic interfaces can influence the selectivity of chemical reactions. Here, using a pre-strained polymer, we uniaxially compress a thin gold film to form a nano-folded catalyst. We observe two kinds of folds and can tune the ratio of loose to tight folds by varying the extent of pre-strain in the polymer. We characterize the nano-folded catalysts using x-ray diffraction, scanning, and transmission electron microscopy. We observe grain reorientation and coarsening in the nano-folded gold catalysts. Electroreduction of carbon dioxide with these nano-folded catalysts reveals an enhancement of Faradaic efficiency for carbon monoxide formation by a factor of about four. This result suggests that electrolyte mass transport limitations and an increase of the local pH in the tight folds of the catalyst outweigh the effects of alterations in grain characteristics. Together, our studies demonstrate that nano-folded geometries can significantly alter grain characteristics, mass transport, and catalytic selectivity. </p>

scholarly journals Struvite Grown in Gel, Its Crystal Structure at 90 K and Thermoanalytical Study

Crystals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 89 ◽  
Author(s):  
Jolanta Prywer ◽  
Lesław Sieroń ◽  
Agnieszka Czylkowska
Keyword(s):  
Thermal Analysis ◽  
Sodium Metasilicate ◽  
X Ray Diffraction ◽  
Gel Growth ◽  
Growth Technique ◽  
Thermoanalytical Study ◽  
X Ray ◽  
Cell Parameters ◽  
Thermal Analysis Techniques ◽  
Derivative Thermogravimetry

In this article, we report the crystallization of struvite in sodium metasilicate gel by single diffusion gel growth technique. The obtained crystals have a very rich morphology displaying 18 faces. In this study, the habit and morphology of the obtained struvite crystals are analyzed. The crystals were examined and identified as pure struvite by single X-ray diffraction (XRD). The orthorhombic polar noncentrosymmetric space group Pmn21 was identified. The structure of the crystal was determined at a temperature of 90 K. Our research indicates a lack of polymorphism, resulting from the temperature lowering to 90 K, which has not been previously reported. The determined unit cell parameters are as follows a = 6.9650(2) Å, b = 6.1165(2) Å, c = 11.2056(3) Å. The structure of struvite is presented here with a residual factor R1 = 1.2% at 0.80 Å resolution. We also present thermoanalytical study of struvite using thermal analysis techniques such as thermogravimetry (TG), derivative thermogravimetry (DTG) and differential thermal analysis (DTA).

Adsorption of the harmful hormone ethinyl estradiol inside hydrophobic cavities of CTA+ intercalated montmorillonite

2016 ◽  
Vol 74 (3) ◽  
pp. 663-671 ◽  
Author(s):  
A. E. Burgos ◽  
Tatiana A. Ribeiro-Santos ◽  
Rochel M. Lago
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
High Efficiency ◽  
Interlayer Space ◽  
Ethinyl Estradiol ◽  
Significant Loss ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrophobic Cavity ◽  
Adsorption Capacities ◽  
Derivative Thermogravimetry

Hydrophobic cavities produced by cetyltrimethylammonium cation (CTA+) exchanged and trapped in the interlayer space of montmorillonite were used to remove the harmful hormone contaminant ethinyl estradiol (EE2) from water. X-ray diffraction, thermogravimetry/derivative thermogravimetry, elemental analysis (carbon, hydrogen, nitrogen), Fourier transform infrared, scanning electron microscopy/energy dispersive spectroscopy, Brunauer–Emmett–Teller and contact angle analyses showed that the intercalation of 9, 16 and 34 wt% CTA+ in the montmorillonite resulted in the d001 expansion from 1.37 to 1.58, 2.09 and 2.18 nm, respectively. EE2 adsorption experiments showed that the original clay montmorillonite does not remove EE2 from water whereas the intercalated composites showed high efficiency with adsorption capacities of 4.3, 8.8 and 7.3 mg g−1 for M9CTA+, M16CTA+ and M34CTA+, respectively. Moreover, experiments with montmorillonite simply impregnated with cetyltrimethylammonium bromide showed that the intercalation of CTA+ to form the hydrophobic cavity is very important for the adsorption properties. Simple solvent extraction can be used to remove the adsorbed EE2 without significant loss of CTA+, which allows the recovery and reuse of the adsorbent for at least five times.

Single Crystal X-ray Diffraction Studies of Carbon Dioxide and Fuel-Related Gases Adsorbed on the Small Pore Scandium Terephthalate Metal Organic Framework, Sc2(O2CC6H4CO2)3

Langmuir ◽  
2009 ◽  
Vol 25 (6) ◽  
pp. 3618-3626 ◽  
Author(s):  
Stuart R. Miller ◽  
Paul A. Wright ◽  
Thomas Devic ◽  
Christian Serre ◽  
Gérard Férey ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Single Crystal ◽  
Metal Organic Framework ◽  
X Ray Diffraction ◽  
X Ray ◽  
Small Pore ◽  
Metal Organic ◽  
Organic Framework

scholarly journals Thermal behaviour study of solid state compounds of manganese (II), zinc (II) and lead (II) with cinnamic acid

1998 ◽  
Vol 23 (0) ◽  
pp. 09-16
Author(s):  
Marco Aurélio da Silva CARVALHO FILHO ◽  
Massao IONASHIRO
Keyword(s):  
Thermal Stability ◽  
Aqueous Solution ◽  
Differential Scanning Calorimetry ◽  
Cinnamic Acid ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Manganese Zinc ◽  
Behaviour Study ◽  
Derivative Thermogravimetry

Compounds of cinnamic acid with manganese, zinc and lead have been prepared in aqueous solution. Thermogravimetry, derivative thermogravimetry (TG, DTG), differential scanning calorimetry (DSC), X-ray diffraction and complexometry have been used in the characterization as well as in the study of the thermal stability and interpretation concerning the thermal decomposition.

Evaluation of the formation and carbon dioxide capture by Li4SiO4 using in situ synchrotron powder X-ray diffraction studies

2018 ◽  
Vol 20 (41) ◽  
pp. 26570-26579 ◽  
Author(s):  
M. L. Grasso ◽  
M. V. Blanco ◽  
F. Cova ◽  
J. A. González ◽  
P. Arneodo Larochette ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Dioxide Capture ◽  
Shell Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Formation Pathway ◽  
Capture Capacity

The formation pathway of Li4SiO4 involves Li2SiO3 as an intermediate. Carbonation of Li4SiO4 under dynamical conditions retards the double shell formation, improving CO2 capture capacity.

Effect of Chemical Composition on the Properties of Reconstructed Steel Slag

2019 ◽  
Vol 944 ◽  
pp. 1163-1171
Author(s):  
Ying Xu ◽  
Qiao Ling Wang ◽  
Chen Guang Hu ◽  
Shan Shan Yang
Keyword(s):  
Compressive Strength ◽  
Steel Slag ◽  
Temperature Reconstruction ◽  
X Ray Diffraction ◽  
Technological Parameters ◽  
Iron And Steel ◽  
X Ray ◽  
Volume Stability ◽  
Cementitious Activity ◽  
Scanning Electron

The steel slag is not widely or extensively used because of its poor volume stability and low cementitious activity. In this paper, the solid waste fly ash, quicklime and slag discharged from iron and steel enterprises are used as conditioning components in the experiment. In order to improve the cementitious activity and volume stability of steel slag, the high temperature reconstruction experiment of steel slag was completed. The effects of C/S (2.50~3.14), S/A (4.5~17. 81) on the cementitious activity and volume stability of reconstructed steel slag were investigated by means of the tests of compressive strength, scanning electron microscope, X-ray diffraction, lithofacies test, stability test and so on. The results showed that the cementitious activity and volume stability of the reconstructed steel slag were improved in the higher C/S or lower S/A. The cementitious activity and volume stability of the reconstructed steel slag were improved with the increase of CaF2 content. By analyzing the cementitious activity and volume stability of the reconstructed steel slag, the optimum technological parameters are obtained as follows: C/S is 2.70 , S/A is 5.78, the content of CaF2 is 4%.

Carbon Dioxide Reforming of Methane over Ni/Mo/La2O3-SBA-15 Сatalyst

2012 ◽  
Vol 455-456 ◽  
pp. 960-965
Author(s):  
Jian Huang ◽  
T. Huang ◽  
A. Rongzhang ◽  
Wei Huang ◽  
Ren Xiong Ma
Keyword(s):  
Carbon Dioxide ◽  
Strong Interaction ◽  
Carbon Deposition ◽  
Catalytic Performance ◽  
Stability Test ◽  
X Ray Diffraction ◽  
Carbon Dioxide Reforming ◽  
X Ray ◽  
Long Term Stability

Carbon dioxide reforming of methane over Ni/Mo/ La2O3-SBA-15 was studied. The catalyst was characterized by N2 adsorption, X-ray diffraction, H2-TPR,CO2-TPD and TG-GTA analysis. The results indicated that the introduction of an appropriate amount of La2O3 exhibited a higher activity and stability. In the long term stability test, La2O3 impregnated Ni/Mo-SBA-15 gave the highest conversion and stable activity at 800°C for 250 h. The effect of La was suggested to be due to its lower tendency to carbon deposition. Characterization results showed a strong interaction between La and Mo or Ni which facilitated the improvement of catalytic performance.

Obtaining Heat-Resistant Materials with the Use of Silica Nanoparticles

2016 ◽  
Vol 683 ◽  
pp. 150-155
Author(s):  
Viktor A. Vlasov ◽  
Pavel V. Kosmachev ◽  
Nelli K. Skripnikova ◽  
Vladimir Otmahov ◽  
Konstantin Bezukhov
Keyword(s):  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Heat Resistant ◽  
Zirconium Silicate ◽  
Tomsk Region ◽  
Zirconium Compounds ◽  
White Clay ◽  
Mass Form ◽  
Derivative Thermogravimetry

Heat-resistant materials are commonly used in industry where technological processes require high temperatures. The research represents possibility to obtain Al2O3–SiO2–ZrO2 based composition from local raw like zirconium silicate of Tugansk deposit of Tomsk region and white clay of Kailinsk deposit of Kemerovo region in Russia. There is possible application in gunning-mass form for restoration industrial thermal units. X-ray Diffraction Analysis demonstrates that mullite and zirconium compounds are formed in samples content after firing. The infra-red spectrums of heat-resistant gunning masses samples have been described by Fourier Transform Infrared Spectroscopy method. The thermal analysis has been performed using Differential Scanning Calorimetry and Derivative Thermogravimetry.

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