scholarly journals Calcined Low-grade Clays as Sources for Zeolite Containing Material

2020 ◽  
Author(s):  
Nailia R. Rakhimova ◽  
Ravil Rakhimov ◽  
Vladimir Morozov ◽  
Aleksey Eskin
Keyword(s):  
Raw Material ◽  
Main Reaction ◽  
Alkali Activation ◽  
Chemical Compositions ◽  
Low Grade ◽  
Material Base ◽  
Reaction Products ◽  
The Sustainable Development ◽  
Technical Requirements ◽  
Alkali Activated

The continuous development and expansion of a raw material base in response to increasing environmental and technical requirements for most consumable commodities are crucial for the sustainable development of resource- and energy-intensive materials and technologies. As the sources for alkali-activated cements and zeolites, recent studies have reported the suitability of applying calcined clays with various chemical compositions, percentages, and constituent clay minerals and secondary minerals. In this article, the results of a feasibility study on the alkali activation of low-grade clays with 7.26 % montmorillonite/chlorite and 23.14 % kaolinite/montmorillonite minerals are reported. The 6M NaOH activation of clays thermally treated at 700 °C results in the formation of a hardened paste with a compressive strength of up to 5 MPa, with an N-(A)-S-H binder gel and zeolite Na2Al2Si2.5O9∙6.2H2O being the main reaction products.

scholarly journals Mechanical Properties of Alkali Activated Material Based on Red Clay and Silica Gel Precursor

2021 ◽  
Vol 25 (1) ◽  
pp. 931-943
Author(s):  
Girts Bumanis ◽  
Danute Vaiciukyniene
Keyword(s):  
Silica Gel ◽  
Raw Materials ◽  
Raw Material ◽  
Alkali Activation ◽  
Production Plant ◽  
X Ray Diffraction ◽  
Red Clay ◽  
Significant Strength ◽  
Naoh Solution ◽  
Alkali Activated

Abstract The search for alternative alumosilicates source for production of alkali activated materials (AAM) is intensively researched. Wide spread of natural materials such as clays and waste materials are one of potential alternatives. In this research AAM was made from local waste brick made of red clay and calcined low-carbonate illite clay precursor and its properties evaluated. Waste silica gel containing amorphous silica from fertilizer production plant was proposed as additional raw material. 6 M and 7 M NaOH alkali activation solutions were used to obtain AAM. Raw materials were characterized by X-ray diffraction, laser particle size analyser, DTA/TG. Raw illite clay was calcined at a temperature of 700 to 800 °C. Waste brick was ground similar as raw clay and powder was obtained. Replacement of red clay with silica gel from 2–50 wt.% in mixture composition was evaluated. Results indicate that the most effective activator was 6 M NaOH solution and AAM with strength up to 13 MPa was obtained. Ground brick had the highest strength results and compressive strength of AAM reached 25 MPa. Silica gel in small quantities had little effect of AAM strength while significant strength reduction was observed with the increase silica gel content. The efflorescence was observed for samples with silica gel.

scholarly journals Mechanism of Alkali-Activated Copper-Nickel Slag Material

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Tingting Zhang ◽  
Haoliang Jin ◽  
Lijie Guo ◽  
Wenchen Li ◽  
Junan Han ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Testing Machine ◽  
Raw Material ◽  
Hydration Reaction ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
Copper Nickel ◽  
Activating Agent ◽  
Cementing Material ◽  
Alkali Activated

A copper-nickel slag-based alkali-activated cementing material (CNSCM) for backfilling was prepared using copper-nickel slag as a raw material and sodium silicate (SS) as an activating agent. The effects of SS content (6%, 8%, and 10%) and curing humidity on the compressive strength of CNSCM were investigated using an electronic universal testing machine. Types of hydration products and microstructures were analyzed by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The results indicated that by increasing the SS content, the compressive strength of the CNSCM exhibited an increasing trend, followed by a decreasing trend. The optimal content was 8%. Humidity was identified as another factor affecting compressive strength, which reached 17 MPa after curing for 28 d under standard conditions. A decrease in humidity could improve the compressive strength of the material. The main hydration reaction products of the CNSCM were C-S-H gel, Fe (OH)2 or Fe (OH)3 gel, and CaCO3.

scholarly journals Fe-modified activated carbon obtained from biomass as a catalyst for α-pinene autoxidation

2021 ◽  
Vol 23 (2) ◽  
pp. 73-80
Author(s):  
Adrianna Kamińska ◽  
Nikola Maciejewska ◽  
Piotr Miądlicki ◽  
Karolina Kiełbasa ◽  
Joanna Sreńscek-Nazzal ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Orange Peel ◽  
Raw Material ◽  
Main Reaction ◽  
Reaction Products ◽  
Modified Activated Carbon ◽  
X Ray ◽  
Alpha Pinene ◽  
Instrumental Methods ◽  
First Time

Abstract The presented work describes the autoxidation of alpha-pinene for the first time using a catalyst based on activated carbon from biomass with introduced Fe. The raw material for the preparation of the carbon material was waste orange peel, which was activated with a KOH solution. The following instrumental methods characterized the obtained catalyst (Fe/O_AC):N2 adsorption at 77 K, XRD, UV, SEM, TEM, X-ray microanalysis, and catalytic studies. It was shown that the Fe/O_AC catalyst was very active in the autoxidation of alpha-pinene. The main reaction products were: alpha-pinene oxide, verbenone, verbenol, and campholenic aldehyde.

scholarly journals Use of Ceramic Sanitaryware as an Alternative for the Development of New Sustainable Binders

2015 ◽  
Vol 668 ◽  
pp. 172-180 ◽  
Author(s):  
Lucía Reig ◽  
M.V. Borrachero ◽  
J.M. Monzó ◽  
Holmer Savastano ◽  
Mauro M. Tashima ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Sanitary Ware ◽  
Pozzolanic Activity ◽  
Raw Material ◽  
Alkali Activation ◽  
X Ray ◽  
Amorphous Phases ◽  
Ceramic Sanitary Ware ◽  
Alkali Activated

Large amounts of ceramic sanitary-ware waste are generated in both the production process and construction and demolition practices. This waste contains amorphous phases that may react with the Portlandite that originates during Portland cement hydration or with an alkali solution, leading to a low CO2-binding material. This study investigated the pozzolanic activity of ceramic sanitary-ware waste, together with its potential to form new binders by alkali activation. For this purpose, raw material was characterized by X-ray diffraction, X-ray fluorescence, particle size distribution, thermogravimetry (TGA) and scanning electron microscopy (SEM). Percentages of ceramic waste of 15 wt.% and 25 wt.%, to replace Portland cement, were used to assess the pozzolanic behavior of this material, and samples were cured at 20oC for different curing times. Alkali-activated samples, in which Ca (OH)2 was used as a source of calcium, and NaOH and sodium silicate solutions were utilized as activators, were cured for 7 days at 65oC. The microstructural evolution of the developed binders was assessed in pastes by SEM and TGA analyses, and mortars were used to evaluate the compressive strength behavior. While some strength gain was observed due to pozzolanic activity, compressive strength values within the 14-36 MPa range were obtained in the alkali-activated mortars in accordance with the activator concentration and the percentage of Ca (OH)2 addition.

scholarly journals Recovery of used acetic acid via sulfuric acid

2021 ◽  
Vol 104 (4) ◽  
pp. 149-162
Author(s):  
Y.B. Raiymbekov ◽  
◽  
U. Besterekov ◽  
P.A. Abdurazova ◽  
U.B. Nazarbek ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Raw Material ◽  
Coefficient Of Determination ◽  
Low Grade ◽  
Acetate Solution ◽  
Material Base ◽  
Technological Parameters ◽  
X Ray ◽  
Acid Method

Kazakhstan has a huge phosphate raw material base, where the basis is made up of micro-grained phosphate ores of the Karatau basin. The depletion of reserves of high-quality commercial ores leads to the search for new methods of using the enrichment and sorting of low-grade technogenic ores, one of which is phosphate-siliceous slates. The presented study was carried out in two stages: at the first stage, phosphate-siliceous shales were enriched by the acetic acid method, regime technological parameters, kinetic and thermodynamic regularities of the process were determined. At the second stage of the research a method for recycling used acetic acid during the enrichment of low-grade phosphate-siliceous slates is proposed. In this case, sulfuric acid was chosen as the regenerating agent of acetic acid. The reliability of the performed studies was proved by the use of modern complex research methods: scanning electron microscopy, Energy Dispersive X-Ray and X-Ray difraction analyses. To determine the course of a particular reaction, a thermodynamic analysis was performed using modern HSC 6.0 software. The kinetic data are determined by calculation. The obtained experimental data were subjected to statistical analysis (Chaddock scale, standard deviation, coefficient of determination). The mechanism of interaction of an acetate solution with sulfuric acid is illustratively described. In conclusion, the sulfuric acid method is suitable for the regeneration of applied acetic acid. In this case, a by-product is formed in the form of calcium sulfate. This product can be used as a building binder (confirmed by the protocol of the “National Center of Expertise” of the Republic of Kazakhstan).

Man-Made Waste as a Raw Material Base for the Production of Modern Construction Composites

2019 ◽  
Vol 23 (7) ◽  
pp. 31-35
Author(s):  
M.S. Saydumov ◽  
S.-A.Y. Murtazaev ◽  
A.Kh. Alaskhanov ◽  
I.S. Dagin ◽  
M.R. Nakhayev
Keyword(s):  
Building Materials ◽  
Materials Science ◽  
Raw Materials ◽  
Construction Materials ◽  
Raw Material ◽  
Chemical Compositions ◽  
Material Base ◽  
Secondary Products ◽  
Natural Sand ◽  
Technogenic Raw Materials

The results of tests of secondary construction materials derived from man-made materials are presented. The granulometric and chemical compositions of secondary products from technogenic raw materials are investigated. The analysis of local natural and man-made raw materials base of the Chechen Republic. The possibilities of using local natural raw materials (crushed stone from gravel, natural sand, gravel, gypsum, cement, etc.) in the technology of building composite materials are shown. The suitability and efficiency of the use of technogenic raw materials in concrete and mortar technology, justified by the complex economic and environmental effect of its use in the practice of building materials science, have been experimentally proved. It has been established that with the introduction of advanced innovations in the field of concrete science it is possible to produce competitive products that are not inferior to foreign analogues.

scholarly journals Effect of Ca(OH)2 Addition on the Engineering Properties of Sodium Sulfate Activated Slag

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4266
Author(s):  
Xiaodi Dai ◽  
Serdar Aydın ◽  
Mert Yücel Yardımcı ◽  
Karel Lesage ◽  
Geert De Schutter
Keyword(s):  
Sodium Sulfate ◽  
Setting Time ◽  
Engineering Properties ◽  
Main Reaction ◽  
Phase Identification ◽  
Reaction Products ◽  
Alkali Activated Slag ◽  
Setting Times ◽  
Activated Slag ◽  
Alkali Activated

Alkali-activated slag is considered as a sustainable construction material due to its environmentally friendly nature. To further promote the sustainable nature of alkali-activated slag, a sodium sulfate activator is suggested to be used since it can be obtained naturally and generates lower greenhouse gas emissions. However, the mixtures activated by sodium sulfate exhibit low early strength and very long setting times. This study investigates the effects of calcium hydroxide (Ca(OH)2) addition on some engineering properties such as rheology, setting time, mechanical properties, porosity, and microstructure of sodium sulfate activated ground granulated blast furnace slag (GGBFS). Furthermore, the changes of chemical groups in reaction products and phase identification have been evaluated by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction. Test results showed that Ca(OH)2 addition can substantially increase the reaction rate and the compressive strength at early ages. In addition, the very long setting times of the sodium sulfate-activated mixtures were shortened by the addition of Ca(OH)2. SEM analysis confirmed that the incorporation of excessive amounts of Ca(OH)2 could lead to a less well-packed microstructure although the reaction degree of GGBFS remained the same at later ages as compared to the sodium sulfate mixture. It was also revealed that in case of the Ca(OH)2 addition into sodium sulfate activator, the main reaction products are chain-structured C-A-S-H gels and ettringite.

scholarly journals Performance Evaluation of Cement-Stabilized Oil Shale Semicoke as Base or Subbase Course Construction Material

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Guojin Tan ◽  
Zhiqing Zhu ◽  
Yafeng Gong ◽  
Chenglin Shi ◽  
Ziyu Liu
Keyword(s):  
Oil Shale ◽  
Resilient Modulus ◽  
Construction Material ◽  
Economic Benefits ◽  
Raw Material ◽  
Low Grade ◽  
Paper Test ◽  
Road Base ◽  
Technical Requirements ◽  
Course Material

Oil shale semicoke is a hazardous byproduct in oil shale retorting process. In Jilin province, China, abundant oil shale resources are mainly used for retorting shale oil accompanying with a large number of oil shale semicoke slags, which will generally cause environmental pollution and disposal problems. If oil shale semicoke can be utilized as a road base or subbase course construction material, it will be a great help to the disposal of a long-term accumulated oil shale semicoke in landfill sites. Moreover, the resource treatment of oil shale semicoke in road project construction could obtain positive social and economic benefits. Subsequently, we conducted a series of laboratory tests to study the practicability of cement-stabilized oil shale semicoke as a road base or subbase course construction material, including the raw material test, modified compaction test, unconfined compressive strength (UCS) test, splitting tensile strength (STS) test, compressive resilient modulus (CRM) test, and freezing-thawing test. In this paper, test results were compared with the technical requirements of Chinese road base construction specification, preliminarily confirming that cement-stabilized oil shale semicoke can be used as a subbase course material of a highway or a base course material of a low-grade highway.

TEM/AEM characterization of fine-grained clay minerals in very-low-grade rocks: Evaluation of contamination by empa involving celadonite family minerals

1996 ◽  
Vol 54 ◽  
pp. 694-695
Author(s):  
Gejing Li ◽  
D. R. Peacor ◽  
D. S. Coombs ◽  
Y. Kawachi
Keyword(s):  
Electron Microscopy ◽  
Volcanic Rocks ◽  
Analytical Electron Microscopy ◽  
Metamorphic Rocks ◽  
New Mineral ◽  
Chemical Compositions ◽  
Low Grade ◽  
Fine Grained ◽  
Depth Analysis ◽  
Mineral Aggregates

Recent advances in transmission electron microscopy (TEM) and analytical electron microscopy (AEM) have led to many new insights into the structural and chemical characteristics of very finegrained, optically homogeneous mineral aggregates in sedimentary and very low-grade metamorphic rocks. Chemical compositions obtained by electron microprobe analysis (EMPA) on such materials have been shown by TEM/AEM to result from beam overlap on contaminant phases on a scale below resolution of EMPA, which in turn can lead to errors in interpretation and determination of formation conditions. Here we present an in-depth analysis of the relation between AEM and EMPA data, which leads also to the definition of new mineral phases, and demonstrate the resolution power of AEM relative to EMPA in investigations of very fine-grained mineral aggregates in sedimentary and very low-grade metamorphic rocks.Celadonite, having end-member composition KMgFe3+Si4O10(OH)2, and with minor substitution of Fe2+ for Mg and Al for Fe3+ on octahedral sites, is a fine-grained mica widespread in volcanic rocks and volcaniclastic sediments which have undergone low-temperature alteration in the oceanic crust and in burial metamorphic sequences.

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