Now showing 1 - 10 of 33
  • Publication
    Correlation Study on the Effect of Sintering Mechanism with the Properties of Geopolymer-Based Ceramic
    Nepheline geopolymer-based ceramics are emerging as a promising alternative to traditional ceramics due to their eco-friendly production and sustainable nature. Therefore, this study aims to comprehensively investigate the relationship between mechanical behaviour and sintering mechanisms in the production of kaolin geopolymer-based nepheline ceramics. Sodium hydroxide and sodium silicate were mixed to act as the alkaline activator to facilitate the geopolymerization process. The experimental analysis involved varying the sintering temperature within the range of 200°C to 1200°C. The findings from the correlation study highlight that the flexural strength and densification process is in linear relation with R2 of 0.9369, whilst the water absorption and volumetric shrinkage exhibited an inversely linear relationship with the R2 value of 0.8733. The maximum flexural strength of 78.92 MPa and density of 2.56 g/cm3 were achieved when sintered at 1200°C. Meanwhile, the water absorption decreases with the increase of volumetric shrinkage, which might relate to the densification process of the geopolymer-based nepheline ceramic. The outcome of this research contributes a deeper understanding of the interplay between mechanical behaviour and sintering mechanism, enabling the design of superior sintered materials.
  • Publication
    Phase analysis of different liquid ratio on Metakaolin/Dolomite geopolymer
    ( 2021)
    Ahmad Syauqi Sauffi
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    ; ;
    Masdiyana Ibrahim
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    ;
    Fakhryna Ahmad Zaidi
    Geopolymer is widely studied nowadays in various scope of studies. Some of the ongoing studies are the study of the various materials towards the geopolymer strength produced. Meanwhile, some of the studies focus on the mixing of the geopolymer itself. This paper discussed the phase analysis of metakaolin/dolomite geopolymer for different solid to the liquid ratio which was, 0.4, 0.6, 0.8, and 1.0, and the properties that affected the geopolymer based on the phases. The constant parameters in this study were the percentage of metakaolin and dolomite used. The metakaolin used was 80% meanwhile dolomite usage was 20%. Besides that, the molarity of NaOH used is 10M and the alkaline activator ratio used is 2.0. All the samples were tested at 28 days of curing. The results show that the 0.8 solid to the liquid ratio used gave better properties compare to other solid to liquid ratio. The phases analyzed were quartz, sillimanite, mullite, and faujasite. The 0.8 S/L ratio shows the better properties compared to others by the test of phase analysis, compressive strength morphology analysis, and functional group analysis.
  • Publication
    Effect of the sintering mechanism on the crystallization kinetics of Geopolymer-Based ceramics
    ( 2023)
    Nur Bahijah Mustapa
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    ; ; ;
    Andrei Victor Sandu
    ;
    Ovidiu Nemes
    ;
    Petrica Vizureanu
    ;
    Christina W. Kartikowati
    ;
    Puput Risdanareni
    This research aims to study the effects of the sintering mechanism on the crystallization kinetics when the geopolymer is sintered at different temperatures: 200 °C, 400 °C, 600 °C, 800 °C, 1000 °C, and 1200 °C for a 3 h soaking time with a heating rate of 5 °C/min. The geopolymer is made up of kaolin and sodium silicate as the precursor and an alkali activator, respectively. Characterization of the nepheline produced was carried out using XRF to observe the chemical composition of the geopolymer ceramics. The microstructures and the phase characterization were determined by using SEM and XRD, respectively. The SEM micrograph showed the microstructural development of the geopolymer ceramics as well as identifying reacted/unreacted regions, porosity, and cracks. The maximum flexural strength of 78.92 MPa was achieved by geopolymer sintered at 1200 °C while the minimum was at 200 °C; 7.18 MPa. The result indicates that the flexural strength increased alongside the increment in the sintering temperature of the geopolymer ceramics. This result is supported by the data from the SEM micrograph, where at the temperature of 1000 °C, the matrix structure of geopolymer-based ceramics starts to become dense with the appearance of pores.
  • Publication
    Production of fly ash-based geopolymer bricks through geopolymerization process
    Utilization of fly ash as a raw material for geopolymer brick production seems to be a logical solution that allows for the conservation of natural resources, abates further pollution and preserves the environment. Fly ash-based geopolymer have been studied by several researchers worldwide for several decades due to their excellent mechanical properties. Geopolymer is a type of amorphous alumino-silicate material which can be synthesized by polycondensation reaction of geopolymeric materials, and alkali solutions. This study has been conducted to produce fly ash-based geopolymer bricks by means of pressure forming without firing procedure and low energy consumptions. The experiments were conducted on fly ash-based geopolymer bricks by varying the ratio of fly ash-to-sand (1:2 - 1:5, by mass of ratio), curing time (1 - 24 hours) and curing temperature (room temperature - 80°C). Compressive strength, water absorption, dimensional test and density analysis was set as the mechanical properties to be tested on the fly ash-based geopolymer bricks. The compression test and water absorption test were measured at 1, 3, 7, 28 and 60 days. Results of the investigation indicated that there was decrease in compressive strength when the ratio of fly ash-to-sand increase. However, the strength was increased with increase in curing time and curing temperature. Compressive strength up to 20.3 MPa was obtained with curing at 70 °C for a period of 24 hours at 60 days of ageing. The density of geopolymer bricks ranged between 1800 Kg/m3 to 1950 Kg/m3. The microstructural properties of fly ash-based geopolymer bricks were investigated by using XRD and SEM analysis.
  • Publication
    Kaolin-based geopolymer as a heavy metal removal: Short review
    ( 2023)
    Ikmal Hakem AZIZ
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    Nurul Ain MAZLAN
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    ;
    Noor Fifinatasha SHAHEDAN
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    Ratna EDIATI
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    ;
    Hamzah FANSURI
    Adsorption procedure have been studies and found to be an effective, easy, and low-cost approach for removing heavy metals from aqueous solution when compared to other methods and technologies. Porous geopolymer will be made by combining aluminosilicate mineral with an alkaline activation solution to be utilized as an adsorbent. This review focuses on the current development in heavy metal removal material. This work also summarize the crucial factors (such as solid-to-liquid ratio, foaming agent ratio, sintering temperatures, and adsorbent dosage) influenced the properties (pore formation, microstructure, chemical bonding, and phase analysis) of kaolin-based geopolymer were highlighted. This review manifests the remarkable potential of kaolin-based geopolymer in high-added value applications.
  • Publication
    The effect of different ratio bottom ash and fly ash geopolymer brick on mechanical properties for non-loading application
    This paper studies the finding of strength and water absorption of geopolymer bricks using bottom ash and fly ash as a geopolymer raw material for non-loading application with minimum strength. The study has been conducted to produce bottom ash and fly ash geopolymer bricks by varying the ratio of fly ash-to-bottom ash, solid-to-liquid and sodium silicate (Na2SiO3)-to-sodium hydroxide (NaOH) in the mixing process. The compressive strength range between 3.8-4.5 MPa was obtained due to the minimum strength of non-loading application with 70°C curing temperature within 24 hours at 7 days of ageing. The optimum ratio selected of bottom ash-to-fly ash, solid-to-liquid and Na2SiO3-to-NaOH are 1:2, 2.0 and 4.0 respectively. The water absorption result is closely related to the amount of bottom ash used in the mix design.
  • Publication
    Geopolymer Ceramic as Piezoelectric Materials: A Review
    ( 2020-07-09)
    Ahmad R.
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    ; ; ;
    Victor Sandhu A.
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    ;
    Waried Wazien Ahmad Zailani
    Diverse application for geopolymer so called inorganic polymer have been expanded as potential to continue growing at a realistic rate where the properties, processing tolerance and economical are comparable with the existing materials. An aluminosilicate inorganic polymer can be produced at low temperature under highly alkali conditions from a solid aluminosilicate and an alkali silicate solution. The conversion of amorphous to semi-crystalline behaviour of geopolymer into crystalline phases upon heating make the method be an alternate way in producing ceramic materials. For another application related to high temperature packaging and enclosure of electronical devices, piezoelectric behavior turn out to be important properties to the geopolymer ceramic materials. This paper summarize the review on the important research findings on the basic geopolymer systems, current knowledge of geopolymer ceramic, and outline potential piezoelectric effect on ceramic materials.
  • Publication
    Effect of Solid-To-Liquids and Na2SiO3-To-NaOH Ratio on Metakaolin Membrane Geopolymers
    ( 2022-01-01)
    Masdiyana Ibrahim
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    ; ;
    Sauffi A.S.
    ;
    Vizureanu P.
    Geopolymer is synthesized by polycondensation of SiO4 and AlO4 aluminosilicate complexes, tetrahedral frames linked with shared sialate oxygen. This paper studies the effect of the solids-to-fluids (S/L) and Na2SiO3/NaOH proportions on the preparing of metakaolin inorganic membrane geopolymer. By consolidating a mixture of metakaolin with sodium hydroxide, sodium silicate and foaming agent, the geopolymer membrane was made in required shape about 1 cm and cured at 80°C for 24 hours. After the curing process, the properties of the samples were tested on days 7. Sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) solution were utilized as an alkaline activator with a NaOH fixation fixed at 10 M. The geopolymer inorganic membrane tests were set up with various S/L proportions (0.8, 1.0, 1.2 and 1.4) and Na2SiO3/NaOH proportions (0.5, 1.0, 1.5, 2.0 and 2.5). Aluminium (Al) powder as a foaming agent was used to create bubbles in porous structure and provide details on the development of membrane geopolymers. This metakaolin membrane, based on the geopolymer, was synthesized by a suspension that depends on the fast cementing mechanism of high-temperature slurries. Porous geopolymeric circles provided a homogeneous composition and quantitative distribution of pores. The water absorption, density, impact toughness testing and microstructure analyses were studied. However, considering the promising results, an adjustment in the mix design of the metakaolin inorganic membrane geopolymer mixtures could increase their mechanical properties without negatively affecting the mechanical properties and porosity, making these sustainable materials a suitable alternative to traditional porous cement concrete.
  • Publication
    A Review of Geopolymer Based Metakaolin Membrane as an Effective Adsorbent for Waste Water Treatment.
    ( 2020-07-09)
    Ibrahim M.
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    ; ;
    Syauqi Sauffi A.
    Geopolymer-based products help eco-accommodating sources of materials such as metakaolin, slag or fly ash. This review explores the blend configuration to generate geopolymer-based metakaolin membrane metakaolin and to evaluate the impact of a range of geopolymer-based metakaolin sintering temperatures at a temperature of 50 °C, 60 °C, 70 °C and 80 °C. As the quick development of a modern culture contributes to a large increase in interest in water, adsorption is taken closer to examined waste water extraction of the adsorption and repulsion of a metakaolin membrane geopolymer. Membrane waste water treatment is chosen to explore simple and inorganic membrane preparation techniques that have long help lives and low production costs. Reviews for geopolymer-based metakaolin membrane were therefore synthesized via a suspension that depends on the quick solidification method of high temperature suspension geopolymer slurries that were used as an adsorbent for treating waste water. Porous geopolymeric spheres have developed a homogenous structure with the aid of electron microscopy and Brunauer Emmett Teller (BET) investigations.Since permeable materials are regularly adsorbents, this examination has analyzed the adsorption by membrane geopolymers of heavy metals. This finding will advance the formation of improved wastewater treatment systems and along these lines give an elective answer for ecological harm brought about by substantial metal contaminations. Along these lines, molar (SiO2/Na2O) ratio of metakaolin and sodium silicate are fundamental in assembling a sort of geopolymer-based inorganic membrane which does not require a high temperature sintering process. Adsorption and dismissal consolidated can be utilized for wastewater auxiliary electrical plating forms not exclusively to proficiently wipe out center and low groupings of overwhelming metals in wastewater yet in addition to wipe out little sub-atomic contaminants in wastewater.
  • Publication
    Synthesis of metakaolin based alkali activated materials as an adsorbent at different Na2SiO3/NaOH ratios and exposing temperatures for Cu2+ Removal
    ( 2023)
    Masdiyana Ibrahim
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    ; ;
    Marcin Nabialek
    ;
    Ramadhansyah Putra Jaya
    ;
    Monthian Setkit
    ;
    ;
    Bartłomiej Jeż
    Water contamination is a major issue due to industrial releases of hazardous heavy metals. Copper ions are among the most dangerous heavy metals owing to their carcinogenicity and harmful effects on the environment and human health. Adsorption of copper ions using alkali activated materials synthesized through the polycondensation reaction of an alkali source and aluminosilicates is the most promising technique, and has a high adsorption capability owing to a large surface area and pore volume. This research focuses on the effect of the alkaline activator ratio, which is a sodium silicate to sodium hydroxide ratio. Various exposing temperatures on metakaolin based alkali activated materials on a surface structure with excellent functional properties can be used as adsorbent materials for the removal of copper ions. A variety of mix designs were created with varying sodium silicate to sodium hydroxide ratios, with a fixed sodium hydroxide molarity, metakaolin to alkali activator ratio, hydrogen peroxide, and surfactant content of 10 M, 0.8, 1.00 wt%, and 3.0 wt%, respectively. Most wastewater adsorbents need high sintering temperatures, requiring an energy-intensive and time-consuming manufacturing process. In this way, metakaolin-based alkali activated materials are adsorbent and may be produced easily by solidifying the sample at 60 °C without using much energy. The specific surface area, water absorption, microstructure, phase analysis, functional group analysis, and adsorption capability of copper ions by metakaolin based alkali activated materials as adsorbents were evaluated. The water absorption test on the samples revealed that the sodium silicate to sodium hydroxide 0.5 ratio had the highest water absorption percentage of 36.24%, superior pore size distribution, and homogeneous porosity at 60 °C, with a surface area of 24.6076 m2/g and the highest copper ion uptake of 63.726 mg/g with 95.59% copper ion removal efficiency at adsorption condition of pH = 5, a dosage of 0.15 g, 100 mg/L of the initial copper solution, the temperature of 25 °C, and contact time of 60 min. It is concluded that self-supported metakaolin based alkali activated material adsorbents synthesized at low temperatures effectively remove copper ions in aqueous solutions, making them an excellent alternative for wastewater treatment applications.