Molar NaOH Research Articles

Development of Detailed Mix Design Methodology for Low Calcium Fly Ash Based Geopolymer Concrete Incorporating OPC and Crumb Rubber

This experimental study proposes a systematic mix-design procedure to develop rubberized geopolymer concrete (RGPC). The developed method is meant to identify the mix ratios for the production of high-strength, low-calcium fly ash-based geopolymer concrete, with OPC as a supplementary binder and crumb rubber as a partial replacement for the fine aggregates. The binder (80% fly ash + 20% OPC) content (350, 375, and 400 kg/m3), crumb rubber percentage (0, 5, 10, and 15%), and NaOH molarity (8, 10, and 12 M) are identified as key variables, with the focus on attaining the targeted compressive strength and workability under heat curing (60 °C). Thirty-six mix designs were tested for their compressive strength after 7 and 28 days, and their graphical relationship with the chosen variables is presented (CR-GPC graphs). A trial experiment with an example is performed to establish the validity of the developed mix-design procedure. It was found that the targeted compressive strength and slump of the rubberized GPC can be achieved with conviction.

Influence of Fe2O3, MgO and Molarity of NaOH Solution on the Mechanical Properties of Fly Ash-Based Geopolymers.

The use of waste from industrial activities is of particular importance for environmental protection. Fly ash has a high potential in the production of construction materials. In the present study, the use of fly ash in the production of geopolymer paste and the effect of Fe2O3, MgO and molarity of NaOH solution on the mechanical strength of geopolymer paste are presented. Samples resulting from the heat treatment of the geopolymer paste were subjected to mechanical tests and SEM, EDS and XRD analyses. Samples were obtained using 6 molar and 8 molar NaOH solution with and without the addition of Fe2O3 and MgO. Samples obtained using a 6 molar NaOH solution where Fe2O3 and MgO were added had higher mechanical strengths compared to the other samples.

Using Artificial Neural Networks for the Prediction of the Compressive Strength of Geopolymer Fly Ash

Geopolymers are promising cement replacement materials as their use results in a considerable reduction of CO2 emissions. Geopolymer Fly ash (GF) is a widely used geopolymer due to its low cost and waste management achievement. The compressive strength of GF depends on variables such as curing time, curing temperature, NaOH molarity, the ratio of sodium silicate to sodium hydroxide, the ratio of fly ash to alkaline solution, etc. Artificial Neural Networks are employed to predict the strength of GF due to their accurate prediction capability as well as saving time and cost of experimental work. The obtained Root Mean Square Error (RMSE) and correction coefficient (R2) values were 4.47 and 0.972 respectively. The results illustrate the ability of the ANN model to be used as an efficient tool in predicting the compressive strength and determining the optimal values of GF parameters. The maximum strength of GF was observed for 2 hours curing time at 100°C, molarity of 10, fly ash to alkaline solution ratio of 3, and sodium silicate to sodium hydroxide ratio of 1.

An Investigation on the Synthesis of Alkali Activated Materials from Thermally Modified Clays

The sustainability and economic competitiveness of alkali activation technology greatly depends on expanding the raw materials database with locally available resources. Therefore, a notable trend has been witnessed toward the exploitation of common clays as alternatives to well-established solid aluminosilicate precursors due to their availability and wide geographical distribution. However, common clays are complex and dedicated research is needed to tailor synthesis procedures and mix designs for different clay resources. This paper describes the outcomes of a study conducted to investigate the influence of several synthesis parameters (solid-to-liquid ratio, NaOH molarity, Si availability, and curing conditions) on the properties of alkali activated binders produced from different thermally modified clays. Optimal synthesis conditions for benchmark metakaolin systems have been identified and binders were produced with progressive dosages of metakaolin replacement by common local clays. Fundamental physical and mechanical properties such as apparent density, open porosity, water absorption, and compressive strength were examined at different curing ages, and X-ray diffraction (XRD) was used to provide complementary mineralogical insights. By combining the effects of the parameters studied, mortar specimens were produced with the developed binders, reaching compressive strength values exceeding 28.2 ± 0.1 MPa, a bulk density as low as 1.78 ± 0.0 g/cm3, and open porosity and water absorption values lower than 15% and 8%, respectively. These properties are comparable to those of conventional hydraulic products, which presents them as interesting candidates for construction. Ultimately, this work aims to contribute with valuable insights toward the valorization of a large group of unexploited clay precursors by demonstrating the feasibility of producing technologically competitive alkali activated materials with little or no use of the prime precursors, thus adding to the extant knowledge and contributing to future scientific and industrial developments in this field.

Performance on Fly Ash Based Geopolymer Concrete with 8, 10 & 12 Molar Naoh Activator Using M40 Grade of Concrete

Abstract: Ordinary Worldwide, Portland cement is a vital building component. A source of carbon dioxide emissions alongside deforestation and the use of fossil fuels is the cement making business. The atmosphere is polluted by greenhouse gases like CO2, which contribute to global warming. CO2 makes up roughly 65% of the greenhouse gases that cause global warming. Around 7% of the planet's total greenhouse gas emissions come from the cement industry. Alternative binders for the manufacturing of concrete are required to overcome the environmental impacts associated with Portland cement. In this work, a geopolymer based on fly ash from Vijayawada with a low calcium content (Class F) was utilised. A thermal power plant was used to create geopolymer concrete. Flyash activation employed an alkaline solution made of sodium silicate and sodium hydroxide solutions. The ratio of alkaline solution to fly ash was adjusted to 0.45. The sodium hydroxide solution's concentration was kept at 8M, 10M, and 12M. (Molars). As ambient curing, different curing conditions for geopolymer concrete were used. At different ages, including 7 and 28 days, the geopolymer concrete's compressive strength and split tensile strength were evaluated. According to the test results, the strength of geopolymer concrete increases along with the alkaline solution to fly ash ratio.

KARAKTERISASI SIFAT FISIKOKIMIA SABUN CUCI PADAT BERBASIS LERAK (Sapindus rarak DC)

Lerak (Sapindus rarak DC.) is one of the fruits with a main active compound called saponin. Saponins function as natural surfactants with foaming and emulsifying properties. Lerak in Indonesia is widely used as a traditional detergent. Using lerak essence as a detergent, batik washing can be done well without fading colors and is more environmentally friendly. Lerak essence can be applied as an additional component in preparing solid laundry soap. Adding lerak essence is to replace the anionic surfactant Sodium Lauryl Sulfate (SLS). Therefore, the risk of pollution can be lowered, as well as keep batik cloth from easily fading out. This study was conducted using Randomized Block Design (RBD) with two factors, including the concentration of lerak essence (10%, 7.5%, and 5%) and NaOH molecules (0.5 mol and 0.375 mol). This study aimed to analyze the effect of variation in lerak essence concentration and NaOH molecular on the physicochemical properties of solid laundry soap. The results showed that the higher the concentration of lerak essence and NaOH molecules, the more it reduces the water content in solid laundry soap. Concentrations of 10% lerak essence and 0.5 mol NaOH molecules have the highest value for foam stability and the lowest value for moisture content. Among the tensile strength, pH, brightness level and yellowness level, the highest value was in the concentration of 7.5% lerak essence and 0.5 mol NaOH molecules. Treatments of the variation of lerak essence concentrations significantly affect pH, while the treatment of NaOH molecular variation significantly affects pH, tensile strength, foam stability, brightness level (L*) and yellowness level (b*).

Canola Meal as Raw Material for the Development of Bio-Adhesive for Medium Density Fiberboards (MDFs) and Particleboards Production.

In the context of natural resource scarcity, environmental challenges and human health concerns, the development of alternative solutions becomes crucial to sustainable development. Sustainable and renewable protein-containing materials such as soy or canola have proved to have wood bonding properties comparable to those of synthetic binders. In addition, the availability of canola meal offers a great possibility for the development of bio-adhesives for the wood-based panel industry. Furthermore, direct utilization of canola meal helps to avoid expensive and low-yield protein isolation processes. Using three different solvent solutions (water and 1 mol and 2 mol sodium hydroxide), canola-based bio-adhesives were prepared and used for the production of medium-density fiberboards (with 10 mm thickness and 800 kg/m3 target density) and three-layer particleboards (with 15 mm thickness and 640 kg/m3 target density). The produced boards were tested for their mechanical properties and dimensional stability according to European norms. With the MDFs’ bending strength values above 40 N/mm2 and internal bonding strength greater than 0.5 N/mm2, the results show that there is indeed a possibility to achieve good mechanical properties using canola meal as a binder. The use of NaOH solutions as denaturants, as well as the addition of colasol, helped improve the bonding properties of the boards by 35.49% and 64.52% for 1 mol and 2 mol NaOH solutions, respectively. The obtained results show that the developed canola-based bio-adhesive can compete with conventional ones. However, despite the good mechanical properties of the produced boards, their poor dimensional stability due to the low water resistance of natural proteins suggests further improvement for industrial application.

Photocatalytic degradation of organic pollutants by Ag2O/AgSiOx

Silver silicate (AgSiOx) is a visible-driven photocatalyst. However, the efficiency of single component photocatalysts can be improved by coupling with other compounds. In this work, AgSiOx was coupled with different amounts of Ag2O using a co-precipitation method. Ratios of Ag2O:AgSiOx were controlled by varying the concentrations of Na2SiO3.9H2O and NaOH. All prepared products were characterized by X-ray diffractometry, transmission electron microscopy, X-ray photoelectron spectroscopy, surface analysis, and UV–vis diffuse reflectance spectroscopy. Under visible light irradiation, the Ag2O/AgSiOx composite could degrade rhodamine B, reactive orange, and bisphenol A solutions. The Ag2O/AgSiOx exhibited greater photocatalytic activity than AgSiOx and Ag2O because this composite improved visible light absorption and inhibited charge recombination. The Ag2O/AgSiOx prepared from 0.012 mol NaOH exhibited the highest photocatalytic activity. Photocatalytic degradation of all pollutant models to low mass species was studied by electrospray ionization mass spectrometry and the cytotoxicity of pollutant model solutions before and after photocatalytic processes was evaluated on L929 mouse fibroblast cells using the MTT assay.

Physico-mechanical and durability properties of new eco-material based on blast furnace slag activated by Moroccan diatomite gel.

Natural diatomite, an amorphous siliceous rock, was used as a source of silica for the synthesis of a silicate gel to replace commercial sodium silicate gel in the synthesis of geopolymers from blast furnace slag at room temperature. Nine diatomite gels were synthesized by varying the diatomite content in the gel by 0, 10, and 15% and the NaOH molarity by 6M, 8M, and 10M. The chemico-mineralogical and microstructural characterization results of the elaborated geopolymers showed that the blast furnace slag activation by diatomite gel under optimal conditions (8M NaOH molarity and 10% diatomite) leads to a good dissolution and polycondensation of the precursor by forming amorphous gels of C-A-S-H type, as well as the mineral phase hydrotalcite, which are the same geopolymerization products detected in the case of the use of conventional silicate gel, and consequently, the obtaining of a geopolymer with interesting physical-mechanical characteristics: compressive strength of 42MPa, density of 1. 61g/cm3, ultrasonic pulse velocity of 3855m/s. Thus, this new approach used in this work proved to be successful in reducing the cost and environmental impact of geopolymers.

HPASC – OPCC bi-surface shear strength prediction model using deep learning

ABSTRACT This research focused on high-performance alkali-activated slag concrete (HPASC) as an overlay material on ordinary Portland cement concrete (OPCC). HPASC specimens were designed with different NaOH molarity, silica fume (SF) content, steel fiber content, age of repair material, and proportion of grooved surface area to the gross area. The results indicated that the steel fibers in HPASC improved the compressive strength and increased the BSS strength. The convolutional neural network (CNN) and multilayered perceptron (MLP) were used to determine a comprehensive model for simulating the effect of each parameter on the BSS shear strength. The simulation results suggest that the CNN, as compared to MLP, can more accurately predict experimental data due to the less MSE and higher R-factor. According to the conducted simulations, HPASC mixed with 2% fibers, 12 molars NaOH solution, 20% SF content, and 30% grooved surface was the most suitable mixture for repair and rehabilitation.

Experimental Study on the Mechanical Properties and Microstructure of Metakaolin-Based Geopolymer Modified Clay.

Clay is found in some countries all over the world. It usually has low compressive strength and cannot be used as a bearing material for subgrade soil. In this paper, the influence of basicity on a metakaolin-based polymer binder to improve clay was studied. The effects of the molar concentration of the alkali activator, different concentration of the metakaolin-based geopolymer and curing time on unconfined compressive strength were studied. The alkali activator-to-ash ratio was maintained at 0.7. The percentage of metakaolin added to the soil relative to metakaolin and soil mixture was 6%, 8%, 10% and 12%. The sodium hydroxide concentrations are 2M, 4M, 6M and 8M. Unconfined compressive strength (UCS) was tested on days 3, 7, 14 and 28, respectively. Compared with original clay, the results show that the unconfined compressive strength increases with the increase in metakaolin content and molar concentration of NaOH. The maximum compressive strength of the sample with NaOH concentration of 8M and percentage of 12% was 4109 kN on the 28th day, which is about 112% higher than that of the original clay. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results showed that the cementing compound covered the clay particles due to the reaction of the geopolymer with the clay, resulting in the formation of adhesive particles. The main purpose of this study is to verify the effectiveness and stability of metakaolin-based geopolymer binder polymerization under normal temperature and a strong alkali environment. The results can provide parameters for the application and promotion of metakaolin-based geopolymers in soil improvement engineering.

The effect of alkaline activators and sand ratio on the physico-mechanical properties of blast furnace slag based mortars

Alkali activation of blast furnace slag with sodium silicate (SS) and sodium hydroxide (NaOH) or potassium hydroxide (KOH) has been extensively studied, however a comprehensive and comparative study between NaOH and KOH activated blast furnace slag without SS is limited, especially in terms of drying shrinkage. Therefore, the present study focused on the effect of using NaOH or KOH as sole alkaline activators to produce alkali-activated slag mortars (AASMs) and to comparatively evaluate their effects on the rheological properties, setting time, drying shrinkage, compressive strength and microstructural properties. Furthermore, statistical analysis was performed to establish relationship between selected parameters. The results showed that using KOH as the sole activator provided advantages such as enhanced fluidity and compressive strength and NaOH provided benefits such as reduced setting time, water absorption and drying shrinkage. In addition, the increase in the molarity of either alkaline solution decreased the yield stress and plastic viscosity of the paste. The X-ray diffraction analysis revealed major peaks of calcium silicate hydrate, calcium aluminosilicate hydrate, and hydrotalcite as reaction products in both NaOH and KOH activated mixes. The higher molarity of NaOH or KOH solution led to a decrease in the total porosity of the paste mixes but increased macro-pores as identified by mercury intrusion porosimetry analysis. The use of higher amount of sand reduced the permeable pore volume and the drying shrinkage of the mortar samples. The development of capillary pore volume and the drying shrinkage were well correlated irrespective of the alkaline activator types and sand ratio. Statistically significant relationships were found to predict compressive strength and drying shrinkage of AASM depending on mix design parameters and curing time.

Characterization of class C and F fly ashes based geopolymers incorporating silica fume

Geopolymers have been proposed as an alternative to ordinary concrete with their appropriate mechanical performances and eco-friendly impacts. In current study investigated the interaction between the class C and F fly ashes on the properties of silica fume incorporated geopolymers. For that purpose, the concentration of the alkali activator were determined according to compressive and flexural strengths. Then, the geopolymers prepared with different fly ash/silica fume ratios at specified alkali activator concentration. Mechanical, physical, chemical and microstructural properties of these geopolymers were evaluated by FT-IR, XRD, TGA, and SEM-EDX. The mechanical properties of geopolymers were enhanced remarkably by NaOH molarity and it was detected that the compressive strength and flexural strength values reached the highest (21.13 ± 1.11 MPa and 6.61 ± 0.56 MPa, respectively) at 10 M. Results were compared according to the fly ash type and the fly ash/silica fume ratios of the geopolymers. Due to the high water demand of silica fume, prominent cracks were seen in the geopolymers including 100% silica fume. Besides, inadequate mechanical properties were obtained when 100% fly ash was used. Consequently, it was clearly revealed that the properties of geopolymers obtained with only fly ash or silica fume were improved by the use of both. Finally, higher mechanical properties (σC: 31.91 ± 1.90 MPa, σF: 8.34 ± 0.23 MPa) and less cracks in the bodies were obtained with class F fly ash (75% wt.).

A statistical models to predict strength development of eight molarity geopolymer concrete

Geopolymer concrete has emerged as a viable alternative to traditional concrete. Geopolymer is amorphous to semi-crystalline materials synthesized from materials generally containing SiO2 and Al2O3 compounds as a source of aluminosilicates. This study aims to develop and validate statistical models to predict the strength development of Geopolymer concrete with 8 molarity of NaOH using data from current experimental work as well as experimental data gathered from local and international literature with different R ratios; SiO2/Al2O3. The present experimental study used binary and ternary systems of source materials, Fly ash FA, Ground Granulated Blast-furnace Slag GGBS, and Metakaolin MK, to achieve different percentages of R ratios ranging from 1.42 to 3.6. Seven Geopolymer concrete mixes with varied R ratios were used in the current experimental portion of the inquiry. Compressive, splitting, and flexural strengths were the characteristics determined. Based on the findings of the trials, it was found that the R ratio has a considerable impact on the mechanical performance of the final product. Results showed that; the compressive strength, splitting tensile strength, and flexural strength at the highest value of R ratio of 3.6 used increased by 362%, 272%, and 333%, respectively, compared with those strengths at the lower R ratio of 2.01 used. Linear and non-linear regression analyses were performed by the Statistical Package for the Social Sciences (SPSS) software version 25 to generate the developed models. The statistical models indicated that the R ratio could reasonably estimate the geopolymer's strength with a statistical correlation coefficient of 0.86, 0.93, and 0.86 for compressive, splitting, and flexural strengths.

Variasi Molaritas Naoh Dan Alkali Aktivator Beton Geopolimer

Cement as a building material for concrete produces CO2 which can damage the earth's atmosphere. Therefore, environmentally friendly geopolymer concrete is the choice. The main ingredients for making this concrete are pozzolanic materials which are rich in Silica (SiO3) and Alumina (Al2O3) as a substitute for cement and alkali activator in the form of Sodium Hydroxide (NaOH) and (Na2SiO3) as binders.This study aims to determine the variation of the mixture for the highest compressive strength. The ratio of fly ash type F and alkali activator is 74%:26%. The molarity of NaOH used was 10M, 12M, 14M, the ratio of Na2SiO3 and NaOH was 2.5:1; 3.0:1; 3.5:1. The test object is cylindrical size 15cm x 30cm and the compressive strength test is 28 days old.The test results with the ratio of NaOH and Na2SiO3 2.5:1 at 10M, 12M, 14M NaOH are 25.81 Mpa, 27.00 MPa, 28.98 MPa. While the compressive characteristics are 24.32 Mpa, 24.67 Mpa, 26.58 Mpa. The test results show that the ratio of molarity and alkali activator greatly affects the compressive strength and workability of geopolymer concrete. High molarity will produce high compressive strength. Meanwhile, the higher the alkali activator ratio, the lower the compressive strength produced.Â

Enhancing class F fly ash geopolymer concrete performance using lime and steam curing

BackgroundProducing fly ash geopolymer concrete (FGPC) which can be cured by air, water, or steam instead of thermal curing without decreasing its mechanical properties will facilitate using FGPC in cast-in situ applications and precast concrete industry. Furthermore, it will decrease the consumed energy in FGPC production. This research attempts to achieve this goal by investigating the efficacy of supplementing class F FGPC with lime while using different curing processes to generate lime-fly ash geopolymer concrete (L-FGPC) that could be a feasible alternative to ordinary FGPC.MethodsThe studied variables included lime content, molarity of sodium hydroxide (NaOH), additional water content, curing type, and moisture of aggregates. The comparative criteria were setting times of fresh concrete, mechanical properties of hardened concrete, and voids ratio. SEM and X-ray diffraction tests were used to validate test results.ConclusionsSteam curing generated the best mechanical properties of L-FGPC. Using 2% lime content with steam-cured L-FGPC yielded proper setting times and the best mechanical properties. Microstructure tests revealed compact microstructure and decreased voids ratio upon using 2% lime content in L-FGPC. Increasing molarity of NaOH, decreasing additional water content, and decreasing moisture of aggregates enhanced L-FGPC’s mechanical properties.

Comparative Study on Strength Characteristics of Fly Ash Based Geopolymer Concrete with 8, 10 & 12 Molar Naoh Activator

Ordinary Portland cement is a major construction material worldwide. Cement manufacturing industry is one of the carbon dioxides emitting sources besides deforestation and burning of fossil fuels. The global warming is caused by the emission of greenhouse gases, such as CO2, to the atmosphere. Among the greenhouse gases, CO2 contributes about 65% of global warming. The cement sector accounts for around 7% of worldwide greenhouse gas emissions of the earth’s atmosphere. In order to address environmental effects associated with Portland cement, Alternative binders for concrete production are needed. Low-calcium (Class F) fly ash-based geopolymer from Vijayawada was used in this study. Geopolymer concrete was made with the help of a thermal power plant. The combination of sodium silicate solution and sodium hydroxide solution was used as alkaline solution for fly ash activation. Alkaline solution to fly ash ratio was varied as 0.45. The concentration of sodium hydroxide solution was maintained as 8M, 10M & 12M (Molars). The curing condition of geopolymer concrete was varied as ambient curing. The compressive strength, Split Tensile Strength of the geopolymer concrete was tested at various ages such as 7 and 28days. From the test results it was found that as the alkaline solution to fly ash ratio increases, the strength of geopolymer concrete also increases.

Assessment of Artificial Intelligence Strategies to Estimate the Strength of Geopolymer Composites and Influence of Input Parameters.

Geopolymers might be the superlative alternative to conventional cement because it is produced from aluminosilicate-rich waste sources to eliminate the issues associated with its manufacture and use. Geopolymer composites (GPCs) are gaining popularity, and their research is expanding. However, casting, curing, and testing specimens requires significant effort, price, and time. For research to be efficient, it is essential to apply novel approaches to the said objective. In this study, compressive strength (CS) of GPCs was anticipated using machine learning (ML) approaches, i.e., one single method (support vector machine (SVM)) and two ensembled algorithms (gradient boosting (GB) and extreme gradient boosting (XGB)). All models’ validity and comparability were tested using the coefficient of determination (R2), statistical tests, and k-fold analysis. In addition, a model-independent post hoc approach known as SHapley Additive exPlanations (SHAP) was employed to investigate the impact of input factors on the CS of GPCs. In predicting the CS of GPCs, it was observed that ensembled ML strategies performed better than the single ML technique. The R2 for the SVM, GB, and XGB models were 0.98, 0.97, and 0.93, respectively. The lowered error values of the models, including mean absolute and root mean square errors, further verified the enhanced precision of the ensembled ML approaches. The SHAP analysis revealed a stronger positive correlation between GGBS and GPC′s CS. The effects of NaOH molarity, NaOH, and Na2SiO3 were also observed as more positive. Fly ash and gravel size: 10/20 mm have both beneficial and negative impacts on the GPC′s CS. Raising the concentration of these ingredients enhances the CS, whereas increasing the concentration of GPC reduces it. Gravel size: 4/10 mm has less favorable and more negative effects. ML techniques will benefit the construction sector by offering rapid and cost-efficient solutions for assessing material characteristics.

Enhanced bio-methane and bio-hydrogen production using banana plant waste and sewage sludge through anaerobic co-digestion

The yield of bio-methane and bio-hydrogen was enhanced by co-digesting banana plant waste (BPW) and sewage sludge (SS). In stage 1, acclimatisation of the inoculum SS is performed in a continuous stirred tank reactor (CSTR), and its various parameters are analyzed daily. In stage 2, six different BPW to SS ratios is optimized and incubated in manual methane potential test setup (MMPTS) for 40 days. The highest bio-methane and bio-hydrogen yields were observed from R4 (60% BPW and 40% SS). In stage 3, the best-achieved ratio of BPW and SS are then treated with different doses of NaOH as an alkaline pre-treatment. The highest bio-methane was achieved from dose 2 (0.75 mol NaOH) as 620.8 NmL/day. The study shows that the co-digestion of the BWP with SS has promising potential for enhanced bio-methane and bio-hydrogen production.

One Shot of the Hydrothermal Route for the Synthesis of Zeolite LTA Using Kaolin

The zeolite LTA (Z-LTA) was successfully produced from the synthesis of kaolin and well-crystallized using a hydrothermal method. The main purpose of the synthesis Z-LTA from kaolin was to illustrate the transformation Z-LTA with different molarity of alkaline solution and crystallization time. The kaolin was heated in the furnace for 4 h at 500, 600, 700, and 800 °C, resulting in a metakaolinization process that transformed it into an amorphous state. The Z-LTA mixture was obtained by dissolving metakaolin in a sodium hydroxide (NaOH) solution without adding other silica or alumina sources. Before going through the hydrothermal synthesis process, the solution mixture was aged for 24 h. The crystal morphology and degree crystallinity (%) of Z-LTA were evaluated using the various molarity (M) of sodium hydroxide (NaOH) and crystallization time (h). The degree crystallinity of the Z-LTA increases from 62.83 to 86.8% when the molarity of NaOH is increased from 0.5 to 1 M but does not increase when the molarity of NaOH is increased to 1 M and 2 M (80.77% and 67.78%), respectively. The degree crystallinity (%) Z-LTA based on molarity proceeded with the various crystallization time (h) factors. 1 M NaOH with 9 h give highest degree crystallinity (88.45%) compared to other time, 12 h (86.16%), 16 h (87.11%), 24 h (86.80%) and 30 h (86.59%) respectively. The crystal morphology structure with Na, Al, O, and Si was seen in SEM images of the Z-LTA at a 1 M NaOH, 9 h crystallization time (Z-LTA, 1 M 9 h). The particle size of (Z-LTA, 1 M 9 h) is smaller, 0.329 µm, than kaolin, 0.497 µm. Under low alkali conditions and crystallization time, the hydrothermal process successfully generates high crystallinity from natural kaolin. As a result, low-grade Malaysian kaolin can be successfully transformed into Z-LTA using the traditional hydrothermal process when the composition parameters are carefully controlled. The hydrothermal synthesis from natural kaolin was the most cost-effective and efficient method, with comparable product quality to zeolite synthesized with conventional raw materials.