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The paper outlines the principles of the directional drilling method with the use of hydraulic fracturing, demonstrating the impact of drilling cuttings and coal combustion waste on the environment. It presents the results of physical and chemical analysis of drilling cuttings from the Vostochno-Chumakovskoye oil field and boiler slag from the OGK-2-Novocherkassk SDPP Branch. In addition, the potential use of boiler slag in the synthesis of aluminosilicate proppants is investigated. [ABSTRACT FROM AUTHOR]

The escalating emissions of CO2 exacerbate global warming. Carbon capture offers a potential avenue to attenuate CO2 emissions, but the high cost of adsorbents acts as a barrier to the development of carbon capture technologies. Simultaneously, the continual increase in coal combustion leads to a rise in fly ash production, yet its valorization remains relatively low. Utilizing fly ash for synthesizing fly ash-based aluminosilicate materials and their application in carbon capture technologies present a dual solution by valorizing industrial solid waste and reducing carbon emissions. The preprocessing steps prior to synthesizing fly ash-based aluminosilicate materials were outlined and the research on synthesis of fly ash-based zeolites, Li4SiO4 adsorbents, and SiO2 mesoporous materials and their synthesis were systematically discussed, and the kinetics of CO2 adsorption on fly ash-based aluminosilicate materials were summarized. Physical and chemical preprocessing steps before preparing fly ash-based aluminosilicate materials optimize the materials' pore structure and surface chemical properties. Strategies such as amine functionalization or metal ion doping enable control over the material structure and CO2 capture performance. Discrepancies in the kinetics of CO2 capture on fly ash-based aluminosilicate materials arise from variations in reaction products and capture conditions. In-depth theoretical research and promoting large-scale engineering applications hold significant promise in guiding the development of carbon capture technologies. [ABSTRACT FROM AUTHOR]

The increase in the cement industry's production, especially the production of Ordinary Portland Cement (OPC), increases the amount of CO2 released into the atmosphere, one of the main greenhouse gases responsible for global warming, with harmful effects on the environment and human health. Against this background, geopolymer concrete is a new type of inorganic polymer material that has attracted the attention of researchers in the building area, due to recycling waste by-products to replace OPC and reducing greenhouse gas (CO2) emissions during its manufacture. It also exhibits better mechanical, thermal, chemical, and electrical properties than OPC-based concrete. In the same environmental context, this material has also attracted the attention of researchers in the wastewater treatment area, because of its specific surface area and the capability of adsorption, photodegradation, and encapsulation of organic and inorganic pollutants. The principal focus of this paper is to provide an in-depth overview of the works that have been undertaken to explore geopolymer-type materials. The paper will attempt to develop a comprehensive database, based on the last research works published between 2010 and 2023 with about 247 references, which explains the elaboration, characterization, and application of these materials in several fields. Therefore, it is estimated that geopolymer composites are promising future candidates for recycling industrial solid waste, the partial or total replacement of OPCs in the construction industry, and the development of adsorbents and catalysts for wastewater treatment.

Fourier-transform infrared (FTIR) spectroscopy is a fast and simple technique for functional group identification. This work provides a review and insight into the application and interpretation of FTIR spectroscopy for cementitious binders that comprise ordinary Portland cement, alkaline-activated binders, geopolymers, and material characterization for civil engineering material applications. This technique can be used to identify different compounds and a moiety of bond vibrations in inorganic molecules such as Si-O, -OH, H-O-H (water), C-O (carbonate or carbonation), aluminosilicate (Si-O-T, where T is Al or Si), and S-O (sulfate or gypsum) found in hydrated cement, alkaline binders, and geopolymers. The prominent bands include those representing carbonation (CO32− 1390–1475 cm−1), calcium carbonate (871, 1792–2516 cm−1), hydroxylation and water molecules (1607, 3400–3650 cm−1), strength skeletal framework compositions or Al-Si substitutions, silicate organization (C-A-S-H, N-A-S-H, or C-S-H (950–1055 cm−1), and sulfate (600–680, 1080–1100 cm−1). Some of the factors that could affect the spectra bands include elemental displacement due to changes in molar mass, activated temperature, pH, activator concentration, w/b ratio, Ca/Si ratio, Si/Al ratio, and the silica modulus (SiO2/Na2O) of the activators used in the binder synthesis. The method could be used for destructive and non-destructive testing on paste sample by using transmission and attenuated total reflectance methods, respectively. [ABSTRACT FROM AUTHOR]

Fourier-transform infrared (FTIR) spectroscopy is a fast and simple technique for functional group identification. This work provides a review and insight into the application and interpretation of FTIR spectroscopy for cementitious binders that comprise ordinary Portland cement, alkaline-activated binders, geopolymers, and material characterization for civil engineering material applications. This technique can be used to identify different compounds and a moiety of bond vibrations in inorganic molecules such as Si-O, -OH, H-O-H (water), C-O (carbonate or carbonation), aluminosilicate (Si-O-T, where T is Al or Si), and S-O (sulfate or gypsum) found in hydrated cement, alkaline binders, and geopolymers. The prominent bands include those representing carbonation (CO32− 1390–1475 cm−1), calcium carbonate (871, 1792–2516 cm−1), hydroxylation and water molecules (1607, 3400–3650 cm−1), strength skeletal framework compositions or Al-Si substitutions, silicate organization (C-A-S-H, N-A-S-H, or C-S-H (950–1055 cm−1), and sulfate (600–680, 1080–1100 cm−1). Some of the factors that could affect the spectra bands include elemental displacement due to changes in molar mass, activated temperature, pH, activator concentration, w/b ratio, Ca/Si ratio, Si/Al ratio, and the silica modulus (SiO2/Na2O) of the activators used in the binder synthesis. The method could be used for destructive and non-destructive testing on paste sample by using transmission and attenuated total reflectance methods, respectively.

Research has been conducted on the use of fly ash from TPP in masses based on a fireclay filler and a clay binder for the production of ceramic aluminosilicate materials for various purposes. It was found that the properties of ceramic materials depend on the clay binder:ash ratio. The regions with higher concentrations of ash in the charge and the firing temperature of samples that establish the properties of the final product are determined, which makes it possible to obtain materials with an apparent density of 1.06 – 1.47 g/cm3 and a compressive strength of 4 – 23 MPa. [ABSTRACT FROM AUTHOR]

In this study, the effects of silica fume on setting time, mortar flow and compressive strength properties of fly ash based flowable geopolymer mortar had been studied. The aluminosilicate binder of 70% fly ash and 30% GGBFS with 2 M of sodium silicate solution (Na2SiO3) is considered as control mix. In the aluminosilicate binder, fly ash had been partially replaced with silica fume (0–30%). The test results indicate that the increase in silica fume up to 20% had shown increment in the geopolymer properties, due to the fine particle size and large surface area of the silica fume. The percentage of silica fume increases beyond 20% decrease in geopolymer properties but, still the mixes shown higher properties than control mix. Later, to improvise the fresh and strength properties, the mix containing 50% fly ash, 30% GGBFS and 20% silica fume is considered as aluminosilicate binder and examined with varying molarity of sodium silicate solution in the region of 1.5 < M < 2. However, the test results are significantly improved with decreasing the molarity of sodium silicate solution. The optimum level of 1.75 M of sodium silicate solution is considered in terms of setting time, mortar flow and compressive strength properties. [ABSTRACT FROM AUTHOR]

In this paper, details and results of experimental and predictive studies carried out to determine the mechanical properties of Aluminosilicate materials like Ground Granulated Blast furnace Slag (GGBS) and Fly Ash (FA) based geopolymer concrete specimens are presented and discussed. The major parameters considered in the experimental study are the percentages of GGBS and Fly ash and the percentage of manufactured sand (m-sand) used to replace conventional river sand used in the production of geopolymer concrete. Sodium hydroxide and sodium silicate solutions were used as the activator in the production of geopolymer concrete. The mechanical properties of the geopolymer concrete determined were the compressive strength, split-tensile strength and flexural strength. The test results showed that the mechanical properties of geopolymer concrete improved with increase in the percentage use of GGBS. Also, it was observed from the test results that increase in the percentage use of m-sand increased the mechanical properties of the geopolymer concrete up to an optimum dosage beyond which reduction in the mechanical properties was observed. The predicted mechanical properties of the geopolymer concrete using Artificial Neural Network (ANN) was found to be in good agreement with the test results. [ABSTRACT FROM AUTHOR]

In this study, the influences of factors and their levels on flowable geopolymer concrete had been examined using Taguchi method. The factors like molarity of sodium silicate (Na2SiO3) solution, percentage of coarse aggregate (CA %), Solution to binder (S/B) ratio and percentage of superplasticizer and each factor varies with three levels as 1.5 M, 1.75 M, 2 M; 40%, 50%, 60%; 0.5, 0.55, 0.6; 0%, 1%, 2% was considered. A total of 9 mixes has been considered as per Taguchi method (L9). It can be observed from the test results that, among the nine Taguchi mixes, the mix T4 is containing 1.75 M of Na2SiO3 solution; 60% of coarse aggregate; solution to binder ratio of 0.6; superplasticizer of 2% had achieved highest slump flow of 650 mm; compressive strength of 29.8 MPa at 28 days and other side the mix T5 is containing 1.75 M of Na2SiO3 solution; 50% of coarse aggregate; solution to binder ratio of 0.5; superplasticizer of 0% had achieved slump flow of 340 mm; compressive strength 47.9 MPa at 28 days. The molarity of the solution is same in the both mixes as 1.75 M. It can be seen that; the mixes are highly influenced by the solution to binder ratio and superplasticizer. Increase in solution to binder ratio and superplasticizer results in increase in slump flow and decrease in strength properties. Therefore, Taguchi analysis is carried out to understand the influences of factors and their levels using Minitab17 software. The optimum level of each factor had been considered in terms of flow and strength properties. Hence, the optimum mix T10 proposed by Taguchi is 1.75 M of sodium silicate solution, 50% of coarse aggregate, S/B ratio of 0.55 and superplasticizer dosage of 1% had achieved 575 mm flow and compressive strength of 52.81 MPa. However, the mix T10 had achieved 11.38% less flow as compared to mix T4 and increase in compressive strength of 10% as compared to T5. Therefore, the comparative study had been carried out between T4, T5 and T10 to determine the optimum mix. [ABSTRACT FROM AUTHOR]

This study analyses the influence of particle size on the dissolution behaviour of three Jordanian raw materials. Kaolin, volcanic tuff and silica sand samples were dissolved in sodium hydroxide solution 10 M at 25 °C, and shaken for 168 h. To better understand the dissolution process, the alkaline solution was renewed after the desired time in order to know the degree of Al-Si raw material removed to the dissolution. The concentrations of leached Al and Si was used to evaluate the dissolution behaviour of the studied raw materials. The three raw materials have higher extent of leaching of Si 4+ and Al 3+ with decreasing the particle size. [ABSTRACT FROM AUTHOR]

Aluminosilicate materials were obtained by sol-gel method, using different Al2O3 and SiO2 precursors in order to prepare sols based on water and organic solvents. As SiO2 precursors, Aerosil 200ι and tetraethoxysilane TEOS: Si(OC2H5)4 were applied, while DisperalTM and aluminium secondary butoxide ATSB: Al(OC4H9)3 were used for Al2O3 ones. Bulk samples were obtained by heating gels at 500 °C, 850 °C and at 1150 °C in air, while thin films were synthesized on carbon, steel and alundum (representing porous ceramics) substrates by the dip coating method. Thin films were annealed in air (steel and alundum) and in argon (carbon) at different temperatures, depending on the substrate type. The samples were synthesized as gels and coatings of the composition corresponding the that of 3Al2O3γ2SiO2 mullite because of the specific valuable properties of this material. The structure of the annealed bulk samples and coatings was studied by FT-IR spectroscopy and XRD method (in standard and GID configurations). Additionally, the electron microscopy (SEM) together with EDS microanalysis were applied to describe the morphology and the chemical composition of thin films. The analysis of FT-IR spectra and X-ray diffraction patterns of bulk samples revealed the presence of -Al2O3 and γ-Al2O3 phases, together with the small amount of SiO2 in the particulate samples. This observation was confirmed by the bands due to vibrations of Al-O bonds occurring in -Al2O3 and δ-Al2O3 structures, in the range of 400 to 900 cm-1. The same phases (γ-Al2O3 and γ-Al2O) were observed in the deposited coatings, but the presence of particulate ones strongly depended on the type of Al2O3 and SiO2 precursor and on the heat treatment temperature. All thin films contained considerable amounts of amorphous phase. [ABSTRACT FROM AUTHOR]

The electrical characterizations of nanoporous zeolite and transport mechanisms were studied for the first time in a wide operating temperature range (28–800 K) and electric field strength (60–200 kV/cm) at room temperature. The influence of temperature, electric field and cell types on the dc conductivity was described. The resistivity decreased from 2.34 × 10 10 to 2.17 × 10 8 Ω m whiles the temperature increased from 28 to 800 K which is associated with the ionic mobility. The existence of water in the channels and pores is the decisive parameter in the ionic transport and it depends strongly on the electric field. When a high voltage was applied to gas discharge gap and porous structure, ionization phenomena increased. In this stage, electronic conduction also contributed to zeolite dc conduction. Therefore, the ionic and electronic transport mechanisms and their interactions are essential in enhancing applications in microdischarge devices with nanoporous zeolite cathodes. [ABSTRACT FROM AUTHOR]

This paper describes a study of the stability of hydrogen peroxide in the presence of different aluminosilicate materials, in connection with an investigation of carboxylic acid perhydrolysis. During the reaction, aluminosilicate materials such as H-β zeolites, mesoporous material H-MCM-41 and alumina initiate the decomposition of hydrogen peroxide. The reason of the spontaneous decomposition of H2O2 is related to the partial dealumination of these zeolites. However, in the case of experiments carried out with H-ZSM-5 zeolite catalysts, a slight catalytic effect on the perhydrolysis and no spontaneous decomposition of hydrogen peroxide were noticed. The use of cation exchange resins as catalysts is more kinetically beneficial than H-ZSM-5 zeolite catalysts. [ABSTRACT FROM AUTHOR]