Effect of the Alkali-Activation on the Mechanical Property of Geopolymer Composite

2014 ◽  
Vol 804 ◽  
pp. 15-18
Author(s):  
Yeong Geum Son ◽  
Woo Keun Lee

In this work, pastes were prepared from slag and MSWI bottom ash by geopolymer technique. And its physical property was evaluated with mixing ratio of sodium silicate and potassium silicate. The amounts of leaching products, such as silica, alumina and calcium ions were changed for mixing ratio of raw materials. The compressive strength was increased with the increment of leaching amount of silica, alumina and calcium ions.

2009 ◽  
Vol 620-622 ◽  
pp. 631-634
Author(s):  
Woo Keun Lee ◽  
Eun Zoo Park ◽  
Ji Hyeon Lee ◽  
Yeong Seok Yoo

In this work, inorganic paste was made from melting slag (MS) of MSWI ash and MSWI bottom ash (MBA) by geopolymer technique. Heavy metals such as Pb and Cu are highly contained in MBA. In the view of environmental protection and resource conservation, recycling of MSWI ash is desirable. MS and MBA were mixed to make inorganic paste. Compressive strength was measured to evaluate the characteristics of inorganic paste after the period of 1, 3 and 7day. Compressive strength of almost 90 MPa was obtained at the mixing ratio of MS : MBA = 9 : 1. And the crystalloid and crystal structure was analyzed by FTIR and XRD. Korea Standard leaching Test (KSLT) is also used to evaluate the environmental safety of inorganic paste. The leached concentration of Pb and Cu were 0.44 ppm and 0.15 ppm, respectively. According to this result, heavy metals were safety immobilized and stabilized.


2019 ◽  
Vol 828 ◽  
pp. 14-17
Author(s):  
Malgorzata Ulewicz ◽  
Jakub Jura

The preliminary results of utilization of fly and bottom ash from combustion of biomass for the produce of cement mortars has been presented. Currently, this waste are deposited in industrial waste landfills. The chemical composition of waste materials was determined using X-ray fluorescence (spectrometer ARL Advant 'XP). ). In the studies sand was replaced by mix of fly and bottom ash from the combustion of biomass in an amount of 10-30% by weight of cement CEM I 42.5 R (Cemex). The obtained cement mortar concrete were subjected to microscopic examination (LEO Electron Microscopy Ltd.) and their compressive strength (PN-EN-196-1), frost resistance (PN-EN 1015-11 and PN-B -04500 ) and absorbability (PN-85/B-04500) were identified. The obtained results showed, the replacement of the cement by mix ashes from combustion of biomass reduce consumption of raw materials and will have a good influence on the environment.


2015 ◽  
Vol 660 ◽  
pp. 3-8
Author(s):  
Laila Mardiah Deraman ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Liew Yun Ming ◽  
Kamarudin Hussin ◽  
Zarina Yahya

Geopolymerization are chemical reaction between raw material and alkaline activator where a rapid change of some partial armorphous, specific structure into a compact cemented framework. It was treated with an alkali silicate solution at 45 – 80 °C whereas it’s formed from reaction of mineral clays or aluminosilicate-bearing industrial waste. The previous study about geopolymer has been done for many years due to the physical and chemical properties which is suitable to use in the construction industry. A Geopolymer material that was containing most Silica (Si) and Aluminium (Al) is such as fly ash, bottom ash, metakaolin and ground granulate blast slag (GGBS). Bottom ash is produced from coal fired thermal power plant and has a physical characteristic similar as sand or gravel sand that makes it ideal for industrial application like a green concrete. The different performance of geopolymer is according to the different content of silica, alumina and calcium. To obtain the best geopolymer material, parameter of raw materials content, the types and ratio of alkaline activators also the curing method will affect the high result of compressive strength. This paper will summarize a previous researchers work about the alkali-activated binder in geopolymer raw materials to become green product.


2021 ◽  
Vol 36 (2) ◽  
pp. 182-191
Author(s):  
Ljiljana Kljajevic ◽  
Miljana Mirkovic ◽  
Sabina Dolenec ◽  
Katarina Ster ◽  
Mustafa Hadzalic ◽  
...  

The potential re-use of red mud in the building and construction industry has been the subject of research of many scientists. The presented research is a contribution to the potential solution of this environmental issue through the synthesis of potential construction materials based on red mud. A promising way of recycling these secondary raw materials is the synthesis of alkali-activated binders or alkali activated materials. Alkali-activated materials or inorganic binders based on red mud are a new class of materials obtained by activation of inorganic precursors mainly constituted by silica, alumina and low content of calcium oxide. Since red mud contains radioactive elements like 226Ra and 232Th, this may be a problem for its further utilization. The content of naturally occurring radionuclides in manufactured material products with potential application in the building and construction industry is important from the standpoint of radiation protection. Gamma radiation of the primordial radionuclides, 40K and members of the uranium and thorium series, increases the external gamma dose rate. However, more and more precedence is being given to limiting the radiological dose originating from building materials on the population these days. The aim of this research was to investigate the possible influence of alkali activation-polymerization processes on the natural radioactivity of alkali activated materials synthesized by red mud (BOKSIT a. d. Milici, Zvornik, Bosnia and Herzegovina) and their structural properties. This research confirmed that during the polymerization process the natural radioactivity was reduced, and that the process of alkali activation of raw materials has an influence on natural radioactivity of synthesized materials.


2011 ◽  
Vol 250-253 ◽  
pp. 849-852
Author(s):  
Wei Xin Hu

A new environment-friendly wall material- the unfired brick is produced by using clay, carbide slag, fly ash and cement as the main raw materials,and certain amount of chemical excitator. The primary mixing ratio is designed on the basis of its mechanical properties and durability. When adopting water curing under normal temperature and atmosphere pressure,the compressive strength,flexural strength and frost resistance of the unfired brick are measured. The results reveal that the optimum mixing ratio for unfired brick is: Carbide slag 30%,fly ash 30%,cement 25% and clay 15%. For the unfired brick formed by vibration with the optimum mixing ratio,the min. compressive strength of each brick is more than 10 MPa, the overall properties meet the requirement as specified in standard JC 239—2001“Fly Ash Brick”.


Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 197
Author(s):  
Jozef Vlček ◽  
Michaela Topinková ◽  
Miroslava Klárová ◽  
Petra Maierová ◽  
Hana Ovčačíková ◽  
...  

Metakaolin (MK) prepared by the calcination of kaolin at 550 °C and fly ash (FA) from the combustion of black coal in a granulating boiler were used to prepare unfired ceramic bonding systems via the alkali activation process. A long-term stability of the mechanical properties of the prepared samples similar to the unfired ceramic systems was observed. The optimal metakaolin and fly ash ratio, the type of the activator (NaOH or water glass) and its concentration were evaluated after the hydration in: a) laboratory conditions; b) hydration box; and c) under the hydrothermal activation. Raw materials and the samples prepared by alkali activation process were characterized by XRD, XRF, TG/DTA, and FTIR methods. The mechanical properties of the prepared samples were tested using a compressive strength test after 2, 28 and 56 days of hydration. The compressive strengths of 16 and 24 MPa after 28 days of hydration were reached for FA samples activated with water glass. The alkali activation of MK was successful in the NaOH solution of the molar concentration above 5 M. The compressive strength values of metakaolin, activated hydrothermally and hydrated at laboratory conditions, reached 11.2 and 5.5 MPa, respectively, for 5 M activator of NaOH.


2013 ◽  
Vol 9 (3) ◽  
pp. 138
Author(s):  
Umi Fathanah ◽  
Sofyana Sofyana

The need of wood as one of raw materials in furniture industry keeps increasing. One of efforts to reduce wood consumption is to develop research by creating composite design from material that contains sellulose to be particle board. Particle board is one of material alternatives that can be wood substitute. The objective of this research is to investigate the effect of natural-adhesive-mixture composition (acacia bark and gambier) with oil-palm-empty bunch toward mechanical property of particle board. Characterization of particle board was carried out by undertaking mechanical property testing (tensile strength and compressive strength) under wet and dry conditions. Composition variations of adhesive and oil-palm-empty bunch were 30:70; 40:60; 50:50; 60:40; 70:30. Making process of particle board is carried out by mixing oil-palm-empty bunch and adhesive with addition of 2% para-formaldehyde and water as much of 10%. Furthermore, the mixture is compressed by using Hot Press at temperature of 150oC and pressure of 10 kg/cm2 for 15 minutes. The research result indicates that the higher the adhesive composition (either adhesives of acacia bark or gambier), particle board resulted is better. In dry condition,  values of the tensile strength of particle boards  that have acacia bark adhesive and gambier adhesive have range of 84.2 - 104 Kgf/cm2 and 83.4 - 81.5 kg/cm2, respectively. Whereas, values of compressive strength of particle boards that have adhesives of acacia bark and gambier are in the range of 6.8 - 10.5 kg/cm2  and 6.3 - 9.3 kg/cm2, respectively. The values of tensile strength and compressive strength are obtained on compositions  of adhesive: oil-palm-empty bunch ≥ 40:60, and they have fulfilled satandard of SNI 03-2105-1996. The values of tensile strength and compressive strength of particle board in wet condition, either adhesives of acacia bark or gambier, have not fulfilled standard of SNI 03-2105-1996.Keywords: empty-bunch-oil palm, acacia bark, gambier, particle board, tensile strength


Detritus ◽  
2019 ◽  
Vol Volume 08 - December 2019 (0) ◽  
pp. 1 ◽  
Author(s):  
Patricia Rabelo Monich ◽  
Fulden Dogrul ◽  
Hugo Lucas ◽  
Bernd Friedrich ◽  
Enrico Bernardo

2014 ◽  
Vol 625 ◽  
pp. 46-49 ◽  
Author(s):  
Rosniza Hanim Abdul Rahim ◽  
Khairun Azizi Azizli ◽  
Zakaria Man ◽  
Tia Rahmiati ◽  
Lukman Ismail

Geopolymer is produced from the alkali activation of materials rich in Si and Al with addition of silicate solution in order to improve the mechanical property. Limited research has been done with the absence of silicate solution in the geopolymerization process by varying solid/liquid ratio and on how it works for that condition on mechanical and physical properties. This paper presents an investigation on the mechanical and physical properties of fly ash based geopolymer by varying solid to liquid ratio using sodium hydroxide as the only activator. In addition, the strength development also been investigated. The samples were prepared using 50mm x 50mm x 50mm mould and cured at an elevated temperature (60oC). It can be observed that the optimum compressive strength and density were obtained at solid/ liquid ratio of 4. In addition, the compressive strength of fly ash based geopolymer for all the solid to liquid ratio increased until 14 days and started to decrease later.


2019 ◽  
Vol 9 (23) ◽  
pp. 5091 ◽  
Author(s):  
Yongzhen Cheng ◽  
Yun Dong ◽  
Jiakang Diao ◽  
Guoying Zhang ◽  
Chao Chen ◽  
...  

This research provides a strategy for partially replacing cement with municipal solid waste incineration (MSWI) bottom ash (BA) to improve the performance of concrete against sulphate attack. Mortar strength tests were performed firstly to evaluate the hydration activity of the ground BA. Concrete specimens were cured in standard conditions and immersed in a solution that contained 10% sodium sulfate. Then, the compressive strength of these specimens was measured to investigate the mechanical properties and durability of the concrete. Next, the capillary porosity of the concrete was determined from the volume fractions of water lost in specimens. Finally, the transport of the sulphate solution in concrete was analyzed using capillary rise, crystallization rate, and solution absorption tests. The results indicated that BA had a certain hydration activity. The equivalent replacement of cement by BA decreased the compressive strength of the specimens but increased the durability of the concrete. There was an excellent correlation between capillary rise height, sulfate solution absorption amount, crystallization rate, and coarse capillary porosity. The addition of BA can decrease the coarse capillary porosity and further slow the capillary transport and crystallization of sulfate solution in concrete. Overall, the replacement of cement with BA can improve the durability of concrete and actualize the utilization of MSWI residues as a resource.


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