Effect of Calcium Hydroxide and Water to Solid Ratio on Compressive Strength of Mordenite-Based Geopolymer and the Evaluation of its Thermal Transmission Property

Author(s):  
Mauricio H. Cornejo ◽  
Jan Elsen ◽  
Bolivar Togra ◽  
Haci Baykara ◽  
Guillermo Soriano ◽  
...  

Mordenite-rich tuff is one of most available zeolitic rocks all over the world. Because of this, the research of natural mordenite as a raw material of geopolymeric materials can provide an almost unlimited source of solid precursor for manufacturing such building materials. Despite efforts to shed light on the behaviour of mordenite-rich tuff during geopolymeric reaction, the performance of these novel materials is barely understood. The aim of this study is to explore the effect of the content of calcium hydroxide, CH, and water-to-solid ratio, W/S, as mixing parameters on compressive strength of mordenite-based geopolymers, MBG, and its thermal conductivity. As solid precursor was used mordenite-rich tuff and mixed with sodium hydroxide (NaOH) at 10M that kept constant during the experiment. Two experimental parameters were selected as independent variables i.e, the content of CH and water-to-solid ratio, and their levels, according to a central composite experimental design. All these designed mixes were characterized by using quantitative X-ray diffraction (QXRD), Fourier Transform Infrared spectroscopy (FTIR), Thermogravimetry and differential scanning calorimetry (TGA-DSC), scanning electron microscopy coupled with energy dispersed spectroscopy (SEM-EDS), in addition thermal conductivity tests were also run according to standard method ASTM C177 at 9, 24, 39°C. The overall results suggested that MBG can be used as building material, however its thermal conductivity was higher than that of commercial isolate building material. The experimental design analysis indicated that the optimum water-to-solid ratio was 0.35, but in the case of the content of CH, the optimum value was not observed on this experimental range because the compressive strength increased as the content of CH increased as well. The compressive strength of MBG was observed in the range between 8.7 and 11.3 MPa. On the other hand, QXRD and FTIR showed that mordenite reacted during the geopolymeric reaction, but instead quartz, also found in zeolitic tuff, acted as inert filler.

2012 ◽  
Vol 204-208 ◽  
pp. 4101-4104 ◽  
Author(s):  
Tzong Ruey Yang ◽  
Ta Peng Chang ◽  
Chun Tao Chen ◽  
Yuan Kai Lee ◽  
Bo Tsun Chen

In this paper, the metakaolin is used as the raw material with aluminosilicate compounds to produce the geopolymer. The effects of three levels of two major controlling factors, the degree of polymerization of the activating solution (weight ratio of SiO2 to Na2O) of 0.4, 0.7 and 1.0 and the weight ratio of liquid to solid (L/S) of 0.7, 0.85 and 1.00 on the engineering properties of geopolymer are investigated. The experimental results show that, at age of 28 days, the compressive strength increases from the lowest 37.33 MPa (SiO2/Na2O = 0.4 and L/S = 0.7) to the highest 71.21 MPa (SiO2/Na2O = 0.7 and L/S = 0.7). While, the thermal conductivity increases from the lowest 0.39 w/mk (SiO2/Na2O = 0.4 and L/S = 1.0) to the highest 0.761 w/mk (SiO2/Na2O = 1.0 and L/S = 0.7).


2021 ◽  
Vol 1047 ◽  
pp. 151-157
Author(s):  
Shoroog Alraddadi

The effect of fine black scoria on the mechanical properties and thermal conductivity of building materials was investigated in this study. Black scoria was used to replace cement in concrete with various percentages. Four concrete samples containing 0%, 10%, 20%, and 30% black scoria were prepared. Characterization black scoria was performed via X-ray powder diffraction, X-ray fluorescence, scanning electron microscopy, thermogravimetric analysis, and differential scanning calorimetry analysis. Then, the compressive strength of the samples was investigated after 14, 21, 28, and 91 days of curing at room temperature. Finally, the thermal conductivities of the samples were measured after 28 days. Based on the experimental results, the highest compressive strength among the samples was 45.3 MPa, obtained from the mixture containing 10% black scoria after 91 days of curing. It was also observed that the average thermal conductivity of the concrete samples decreased with an increase in the fine black scoria content from 1.8 to 0.193 W m−1 K−1. Thus, black scoria is an appropriate substitute for commercial admixtures in cement composites in thermally insulating building materials due to its low density, excellent compressive strength, and good heat insulation properties.


2019 ◽  
Vol 25 (4) ◽  
pp. 43-49
Author(s):  
LUCIAN PAUNESCU ◽  
MARIUS FLORIN DRAGOESCU ◽  
SORIN MIRCEA AXINTE ◽  
ANA CASANDRA SEBE

The paper presents an aluminum foam experimental technique using the microwave energy. The raw material was recycling aluminum waste processed by ecological melting and gas atomizing to obtain the fine powder required in the foaming process. The powder mixture was completed with dolomite as a foaming agent. The products had a fine and homogeneous porous structure (pore size between 0.4-0.9 mm). The density (1.17-1.19 g/cm3), the compressive strength (6.83-7.01 MPa) and the thermal conductivity (5.71-5.84 W/m·K) had values almost similar to the foams made by conventional methods.


2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Neslihan Doğan-Sağlamtimur ◽  
Adnan Güven ◽  
Ahmet Bilgil

Pumice, cements (CEM I- and CEM II-type), waste fly and bottom ashes (IFA, GBA, and BBA) supplied from international companies were used to produce lightweight building materials, and physical-mechanical properties of these materials were determined. Axial compressive strength (ACS) values were found above the standards of 4 and 8 MPa (Bims Concrete (BC) 40 and 80 kgf/cm2 class) for cemented (CEM I) pumice-based samples. On the contrary, the ACS values of the pumice-based cemented (CEM II) samples could not be reached to these standards. Best ACS results (compatible with BC80) from these cemented lightweight material samples produced with the ashes were found in 50% mixing ratio as 10.6, 13.2, and 20.5 MPa for BBA + CEM I, GBA + CEM II, and IFA + CEM I, respectively, and produced with pumice were found as 8.4 MPa (same value) for GBA + pumice + CEM II (in 25% mixing ratio), BBA + pumice + CEM I (in 100% mixing ratio), and pumice + IFA + CEM I (in 100% mixing ratio), respectively. According to the results, cemented ash-based lightweight building material produced with and without pumice could widely be used for constructive purposes. As a result of this study, an important input to the ecosystem has been provided using waste ashes, whose storage constitutes a problem.


Author(s):  
Viola Hospodarova ◽  
Nadezda Stevulova ◽  
Vojtech Vaclavik ◽  
Tomas Dvorsky ◽  
Jaroslav Briancin

Nowadays, construction sector is focusing in developing sustainable, green and eco-friendly building materials. Natural fibre is growingly being used in composite materials. This paper provides utilization of cellulose fibres as reinforcing agent into cement composites/plasters. Provided cellulosic fibres coming from various sources as bleached wood pulp and recycled waste paper fibres. Differences between cellulosic fibres are given by their physical characterization, chemical composition and SEM micrographs. Physical and mechanical properties of fibre-cement composites with fibre contents 0.2; 0.3and 0.5% by weight of filler and binder were investigated. Reference sample without fibres was also produced. The aim of this work is to investigate the effects of cellulose fibres on the final properties (density, water absorbability, coefficient of thermal conductivity and compressive strength) of the fibrecement plasters after 28 days of hardening. Testing of plasters with varying amount of cellulose fibres (0.2, 0.3 and 0.5 wt. %) has shown that the resulting physical and mechanical properties depend on the amount, the nature and structure of the used fibres. Linear dependences of compressive strength and thermal conductivity on density for plasters with cellulosic fibres adding were observed.


Proceedings ◽  
2019 ◽  
Vol 34 (1) ◽  
pp. 22
Author(s):  
Bouzit ◽  
Taha

The building sector is one of the largest energy consumers in the world, prompting scientific researchers to find solutions to the problem. The choice of appropriate building materials presents a considerable challenge for improving the thermal comfort of buildings. In this scenario, plaster-based insulating materials have more and more interests and new applications, such as insulating coatings developing the building envelope. Several works are being done to improve energy efficiency in the building sector through the study of building materials with insulation quality and energy savings. In this work, new composite materials, plaster-gypsum with mineral additives are produced and evaluated experimentally to obtain low-cost materials with improved thermo-physical and acoustic properties. The resulting composites are intended for use in building walls. Plaster-gypsum is presented as a high-performance thermal material, and mineral additives are of great importance because of their nature and are environmentally friendly. Measurements of thermal properties are carried and measurements of acoustic properties. The results show that it is possible to improve the thermal and acoustic performance of building material by using plaster as a base material and by incorporating thermal insulators. The thermal conductivity of plaster alone is greater than that of plaster with mineral additives, offer interesting thermal and acoustic performance. By varying the additives, the thermal conductivity changes. Finally, comparing the results, plaster with mineral additives is considered the best building material in this study


2019 ◽  
Vol 31 (5) ◽  
pp. 1045-1048
Author(s):  
Quang Thuong Tran ◽  
Loan Thi Thanh Vu ◽  
Tram Huyen Le ◽  
Ly Thi Phuong Giang ◽  
Toyonobu Usuki

The objective of this study was to evaluate the effects of extraction parameters (ethanol concentration, extraction ratio of solvent to raw material and extraction time) on the yield of spinosin from the seeds of Ziziphus mauritiana Lam. Box-Behnken factorial design was used in association with response surface methodology. The optimal extraction conditions were an ethanol concentration of 61 %, 40 (v/w) liquid-to-solid ratio, and 2.6 h extraction time with reflux. Spinosin was purified using Diaion HP20SS as an adsorbent. The maximum spinosin yield was 1.18 mg/g raw material. Present findings can be applied to future approaches for maximizing the extraction of spinosin from Z. mauritiana Lam. seeds.


2013 ◽  
Vol 853 ◽  
pp. 202-206 ◽  
Author(s):  
Tsung Yin Yang ◽  
Chuan Chi Chien

Zinc and aluminum powders were used as foaming agents and organosilane was innovatively used as a modifier to synthesize a foamed geopolymer. The produced foamed geopolymer with enhanced compressive strength and low thermal conductivity is an ideal material for fire protection, sound absorption and thermal insulation. The low thermal conductivity was achieved by increasing the porosity in the foamed geopolymer and the enhanced compressive strength was realized by adding the modifier. The pore numbers in the foamed geopolymer were greatly increased by releasing the hydrogen gas, which was produced from the chemical reaction of zinc and aluminum powders in a base solution. The modifier decreased the foaming reaction rate and generated homogeneously-distributed small pores in the foamed geopolymer with improved compressive strength.


2012 ◽  
Vol 512-515 ◽  
pp. 590-595 ◽  
Author(s):  
Ya Mei Lin ◽  
Cui Wei Li ◽  
Feng Kun Yang ◽  
Chang An Wang

Porous anorthite/mullite composite ceramics with different mullite content were fabricated by foam-gelcasting, using CaCO3, SiO2, α-Al2O3as raw material for anorthite phase and mullite powder for mullite phase. Effects of mullite powder content on bulk density, porosity, compressive strength and thermal conductivity of the porous composite ceramics were researched. It has been shown that mullite powder content has great effect on microstructure and properties of the porous anorthite⁄mullite composite ceramics. The open porosity of the prepared porous anorthite⁄mullite composite ceramics is in the range of 58.7 %~77.5 %, the compressive strength is between 4.2 and 30.9 MPa, and the thermal conductivity is in the range of 0.18 ~1.47 W⁄(m·K).


2016 ◽  
Vol 690 ◽  
pp. 109-113 ◽  
Author(s):  
Sutthima Sriprasertsuk ◽  
Phatthiya Suwannason ◽  
Wanna T. Saengchantara

This work investigated the recycling of fly ash waste and cullet as the raw materials for lightweight bodies produced by heat treatment and using sodium silicate as the binder. Borax was mixed with fly ash and cullet, and put into the block in dimension 10x10x2 cm3. The lightweight materials thus produced were then sintered at temperature of 800 °C. Density, compressive strength and thermal conductivity were determined. Borax showed a positive sintering effect on the porosity of lightweight material during the heat process. The compressive strength of lightweight material diminished with the reduction of density and thermal conductivity. Lightweight material manufactured with borax showed the lower density and thermal conductivity accompanied by the higher compressive strength. The test results indicated that using fly ash and cullet as the raw material with borax could obtain the lightweight material, thus enhancing the possibility of its reuse in a sustainable way.


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