Influence of the mineralogical composition, specific surface area and strains — Crystallite size of alite on the compressive mechanical strength of portland mortars. II. Clinkers of high tricalcium aluminate contents

The influence of glycine, glycerine, ethylene glycol and citric acid fuel and their ratio to NO3- on formation and dispersity of Bi2WO6 nanoparticles prepared by combustion synthesis has been studied. The pure crystalline Bi2WO6 with specific surface area 24,8 m2/g and crystallite size of 28 nm was obtained by using glycerine as fuel at its ratio to NO3- of 0,67. The photocatalytic activity of the prepared Bi2WO6 in degradation of methylene blue depended on its specific surface area of samples and solution pH.

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Mineralogical study of clays from Dobrodo, Serbia, for use in ceramics

Clay Minerals ◽

10.1180/clm.2019.49 ◽

2019 ◽

Vol 54 (4) ◽

pp. 369-377 ◽

Cited By ~ 1

Author(s):

Maja Milošević ◽

Predrag Dabić ◽

Sabina Kovač ◽

Lazar Kaluđerović ◽

Mihovil Logar

Keyword(s):

Specific Surface ◽

Cation Exchange ◽

Surface Area ◽

Specific Surface Area ◽

Cation Exchange Capacity ◽

Mineralogical Composition ◽

Exchange Capacity ◽

Mineralogical Characterization ◽

Mineralogical Study

AbstractThis study focuses on the mineralogical characterization of four raw clay samples from Dobrodo deposit, Serbia. Several analytical methods were applied to determine the chemical and mineralogical composition, morphology and physical properties (colour, plasticity, specific surface area, particle size and cation-exchange capacity) of the clay samples. Kaolinite, smectite and illite are the predominant phases in all of the samples studied that contain between 60.2 and 87.1 wt.% of clay. Quartz, feldspars, paragonite and Ti- and Fe-bearing phases were also identified. The relatively high SiO2/Al2O3 mass ratio indicates abundant quartz. The cation-exchange capacity of the samples varied between low and moderately charged clay minerals (12–52 mmol 100 g–1) with specific surface area values ranging from 94 to 410 m2 g–1. The plasticity index values (11–23%) suggest low to moderate plasticity. Preliminary results show that most of the raw clay from Dobrodo deposit might be suitable for use in ceramic applications.

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Zeolite Synthesis from Brazilian Coal Fly Ash for Removal of Zn2+ and Cd2+ from Water

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.356-360.1900 ◽

2011 ◽

Vol 356-360 ◽

pp. 1900-1908 ◽

Cited By ~ 3

Author(s):

Juliana De Carvalho Izidoro ◽

Denise Alves Fungaro ◽

Shao Bin Wang

Keyword(s):

Fly Ash ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Metal Ion ◽

Raw Materials ◽

Coal Fly Ash ◽

Mineralogical Composition ◽

Batch Process ◽

Metal Ion Removal

A Brazilian fly ash sample (CM1) was used to synthesize zeolites by hydrothermal treatment. Products and raw materials were characterized in terms of real density (Helium Pycnometry), specific surface area (BET method), morphological analysis (SEM), chemical composition (XRF) and mineralogical composition (XRD). The zeolites (ZM1) from fly ash were used for metal ion removal from water. Results indicated that hydroxy-sodalite zeolite could be synthesized from fly ash sample. The zeolite presented higher specific surface area and lower SiO2/Al2O3ratio than the ash precursor. The adsorption showed that cadmium is more preferentially adsorbed on ZM1 than zinc. The adsorption equilibrium time for both Zn2+and Cd2+was 20 hours in a batch process. The adsorption isotherms were better fitted by the Langmuir model and the highest percentages of removal using ZM1 were obtained at pH 6 and 5 and doses of 15 and 18 g L-1for Zn2+and Cd2+, respectively. Thermodynamic studies indicated that adsorption of Zn2+and Cd2+by ZM1 was a spontaneous, endothermic process and presented an increase of disorder at the interface solid/solution.

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Changes in Particle Size and Crystallinity in Ground Nickel Powder

Materials Science Forum ◽

10.4028/www.scientific.net/msf.587-588.468 ◽

2008 ◽

Vol 587-588 ◽

pp. 468-472

Author(s):

J.M. González ◽

José A. Rodríguez ◽

Enrique J. Herrera

Keyword(s):

Particle Size ◽

Specific Surface ◽

Crystallite Size ◽

Surface Area ◽

Specific Surface Area ◽

Nickel Powder ◽

Milling Time ◽

High Energy ◽

Published Data ◽

Average Particle

Nickel powder was dry-milled using a high-energy disc-oscillating mill. The average particle size increases and the specific surface area diminishes with milling time. Crystallite size decreases and microstrains increase, under the same conditions, as shown by X-ray analysis. At 120 min milling time, the crystallite size has a value of 17 nm, i.e., a nanostructured powder, with a perturbed lattice, is obtained. The above results have been compared with published data about the effects of milling on a ceramic powder. There is, in both cases, a general agreement concerning the changes produced in crystallite size. Nevertheless, opposite results are reached regarding particle size and specific surface area.

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Mineralogy, chemistry, and physical properties interrelationships of some sensitive clays from Eastern Canada

Canadian Geotechnical Journal ◽

10.1139/t84-055 ◽

1984 ◽

Vol 21 (3) ◽

pp. 530-540 ◽

Cited By ~ 75

Author(s):

Jacques Locat ◽

Guy Lefebvre ◽

Gérard Ballivy

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Clay Fraction ◽

Internal Standard ◽

Mineralogical Composition ◽

Index Properties ◽

X Ray Diffraction ◽

Eastern Canada ◽

Quantitative Mineralogy

This paper describes the use of quantitative mineralogy and specific surface area in interpreting the index properties of clayey soils from nine sites in Eastern Canada. Samples representative of the Tyrrell, Laflamme, Champlain, and Goldthwait marine seas and Lac Barlow–Ojibway have been studied.Quantitative X-ray diffraction analyses may be satisfactorily obtained using potassium metaperiodate (Foscal-Mella 1976) as an internal standard in these soils. Determination of contained amorphous matter requires extraction procedures less brutal than those employed in the Ségalen method.Correlations between Atterberg limits and specific surface area are believed to be more useful than those between specific surface area and the grain size or clay fraction. Increases in plasticity and specific surface area are related to increases in the amount of contained phyllosilicates and amorphous matter.The mineralogical composition of the soils studied is dominated, even in the clay fraction, by felsic minerals (plagioclase, quartz, microcline, and hornblende). Samples close to the Canadian Shield contain relatively more felsic minerals than those away from it. Key words: mineralogy, index properties, sensitive clays, physicochemistry.

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The Influence of Dry Hydrated Limes on the Fresh and Hardened Properties of Architectural Injection Grout

Materials ◽

10.3390/ma14195585 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5585

Author(s):

Andreja Padovnik ◽

Violeta Bokan-Bosiljkov

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Mineralogical Composition ◽

Hydrated Lime ◽

Water Retention Capacity ◽

Retention Capacity ◽

Limestone Filler ◽

Hardened Properties ◽

Mechanical Strengths

Dry hydrated lime is an air binder often used in architectural injection grouts. This study compared the influences of three commercially available dry hydrated limes on the injection grouts’ workability and mechanical properties. The main differences between the limes were in their chemical and mineralogical composition and Blaine specific surface area. The grouts were composed of dry hydrated lime, finely ground limestone filler, water, and super plasticiser. Subsequent results obtained revealed that the Blaine specific surface area is not directly related to the fresh grout properties. Grain size distribution and shape of lime particles and their aggregates in the water suspension are key parameters influencing the following fresh grout properties: fluidity, injectability, the mixture’s stability, and water retention capacity. However, the lime injection grouts’ mechanical strengths were higher in relation to an increase in the content of portlandite and the Blaine specific surface area of the dry hydrate.

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