Papers by Keyword: Zeolite

Abstract: This investigation was carried out in a lab setting with the aid of a filter set. This study aimed to lower the level of clean water contamination and assess the filter media's performance in Fitu Village, Ternate City, using physical and chemical criteria. Temperature, turbidity, total dissolved solids (TDS), and odour are physical parameters. While pH, Mn (manganese), and Fe (iron) are the chemical parameters. Sand-activated carbon made of silica and zeolite is the filter medium. One hundred eighty litres of water from a resident's well make up the sample. The physical characteristics, namely the TDS of 1250 mg/L, the turbidity of 27 NTU, and the temperature of 25 °C, show the outcomes of investigating healthy water as raw water in the Kelurahan Fitu. Fe concentration was 1.3 mg/L, Mn concentration was 0.6 mg/L, and pH was 9. Water is passed via silica sand, zeolite, and activated carbon filters before entering the filter after further inspection. According to the results, the TDS has dropped to 897 mg/L, the turbidity has changed to 24, and the temperature is 24 °C. The filtered water meets the chemical standards for Fe concentration with only 0.91 mg/L of Fe, 0.45 mg/L of Mn, and a pH of 7.9. According to the study's findings, inhabitants of Fitu Village in Ternate City can efficiently reduce pollutants and metal levels in their healthy water by employing a filtering system that uses silica sand filter media, zeolite, and activated carbon.

Abstract: Water resources are crucial in any region's overall natural resource complex. This research focuses on addressing these pollution issues through water treatment processes. The primary objective of this study was to examine the adsorption of phosphates using both natural and synthetic adsorbents, particularly aluminosilicates. Under static and dynamic conditions, the research assessed the sorption characteristics of natural zeolite, specifically clinoptilolite obtained from the Sokyrnytsia mineral deposits. Results indicated that the adsorption of phosphates is more effective in acidic environments. It was observed that clinoptilolite exhibits a higher adsorption capacity for unsubstituted phosphates, which diminishes when alkali metal ions replace orthophosphoric acid. Additionally, the study highlighted the significant influence of pH levels on the sorption properties of clinoptilolite, especially about P₂O₅. The kinetic coefficients of the adsorption process were determined using experimental data and theoretical frameworks. Furthermore, mathematical modelling was employed to describe the adsorption dynamics of the active components by granular sorbents, effectively capturing the transient nature of diffusive-kinetic processes in complex, multicomponent systems. This research deepens our understanding of phosphate adsorption mechanisms. It provides valuable insights into optimising water treatment strategies using natural adsorbents, which could play a critical role in mitigating the effects of water pollution in the region. Zeolites derived from fly ash produced by the Dobrotvir thermal power plant have been synthesised and modified to enhance their properties. This study focuses on the characteristics of these zeolites, with a particular emphasis on thermogravimetric analysis, to understand their stability and performance under varying conditions. The adsorption capabilities of the natural zeolite were tested against common pollutants found in wastewater from meat-processing plants, specifically targeting ammonium and phosphate contaminants. Experimental data allowed for determining equilibrium adsorption capacities and corresponding isotherms were constructed at a standard temperature of 20°C. The results indicate that zeolite adsorbs phosphates more effectively than ammonia nitrogen. Further analysis revealed that clinoptilolite's adsorption capacity is higher when interacting with single-component systems but decreases when it simultaneously adsorbs two different substances from the solution. This decrease suggests competitive adsorption dynamics when multiple contaminants are present. Given the finite availability of natural zeolite resources, this research highlights the importance of synthesising synthetic zeolites as a sustainable alternative.

Abstract: This research project focuses on the experimental investigation of using zeolite as a partial replacement for cement in M25 grade concrete. Zeolite, a naturally occurring mineral with pozzolanic properties, has gained attention as a sustainable alternative to cement in concrete production. The study aims to assess the effects of incorporating zeolite on the properties of M25 concrete, such as compressive strength, durability, and workability. Through a series of laboratory tests and analysis, the project intends to evaluate the feasibility and effectiveness of utilizing zeolite in reducing cement content while maintaining the required performance standards of M25 concrete. The findings of this research could contribute to promoting eco-friendly practices in the construction industry by reducing the environmental impact of cement production.

Abstract: The limitations of river water resources and river sand have driven the development of concrete that uses sea sand and seawater as alternative raw materials. The use of concrete with sea sand and seawater has been the focus of previous research to enhance the properties and strength of the concrete. In this study, natural zeolite powder, which is a natural material containing high silica (SiO₂) and alumina (Al₂O₃), was utilized. The finely ground zeolite powder was added to the concrete mix with three variations: 5%, 7.5%, and 10% from weight of cement. The main objective of this research is to evaluate the mechanical properties of concrete using sea sand and seawater at the age of 14 and 56 days, comparing it with concrete using river sand and river water. Test results show a significant increase in compressive strength of concrete with the addition of zeolite powder, especially at the 7.5% concentration, compared to zeolite-free concrete. Although a decrease in compressive strength occurred at 56 days compared to 14 days, this decrease did not exceed the compressive strength value of zeolite-free concrete. Additionally, in the split tensile strength test of concrete, the results show positive development, with an increase in the split tensile strength value at 56 days, especially at the zeolite concentrations of 7.5% and 10%, compared to 14 days. This indicates that the addition of zeolite can enhance the concrete's ability to resist tensile forces, making it suitable for structures requiring high tensile strength.

Abstract: Clay minerals possess substantial potential for developing innovative functional materials, particularly in the context of environmental protection. This study focuses on the adsorbent zeolite-clay and bentonite-clay, shaped into honeycomb monoliths to efficiently remove Fe²⁺ ions from water. The process involved physically activating powdered zeolite-clay and bentonite-clay through calcination at 600°C. The activated materials were then mixed with distilled water and molded into monolithic shapes through extrusion with stainless steel molds, resulting in cylindrical structures measuring 1.8 cm in diameter and 2 cm in height, featuring 40 perforations. Mechanical characterization aimed to evaluate structural strength and assess pressure drop during operation, revealing superior mechanical strength in bentonite-clay compared to zeolite-clay. The monolithic form exhibited lower pressure drop during operation compared to pellet adsorbents. In terms of adsorption performance, a batch reactor assessed efficiency, isotherm, and kinetics with 2 and 4 ppm Fe2+ ion solutions over a 240-minute period. The zeolite-clay monolith demonstrated the highest capacity, achieving a removal efficiency of up to 65%. Maximal adsorption capacities for bentonite-clay and zeolite-clay were 0.209 and 0.289 mg/g, respectively, with corresponding Langmuir adsorption equilibrium constants (KL) of 0.187 and 0.181 L/g by the Langmuir isotherm model. Kinetic analysis favored the pseudo-first-order non-linear model, indicating rates for zeolite-clay and bentonite-clay adsorbents at 2 and 4 ppm Fe²⁺ ion concentrations of 0.0043, 0.0030, 0.0039, and 0.0038 min^-1. This study signifies a significant advancement in solid adsorbents, optimizing the adsorption process for broader applications.

Abstract: The article presents the results of studies of the chemical stability of solidified radioactive waste with alkali cement through long-term leaching. Efficiency of application of alkaline slag Portland cement type LCEM IV as a matrix for reliable chemical and physical binding of caesium ions in the compound for long-term burial we confirmed. Modification of alkaline cement by additions of magnetite from 5 to 8.3% and zeolite in the amount from 4.2 to 5% promotes additional sorption of caesium ions in solidification products of alkaline matrix at maximum content of radioactive waste up to 17.5%. It they noted that the maximum values of sorption capacity of compounds (from 42000 to 68000 ml/g) we observed on the 14th day of the leaching process. They are characteristic for compounds containing magnetite from 5 to 8.3%, zeolite - from 4.2 to 7.5% and radioactive waste from 10 to 15%. It is shown that on the first day of leaching the highest rate (8.35E-02 g/сm²day) is characterised by compositions containing magnetite from 5 to 8.3%, zeolite from 4.2 to 5% and radioactive waste from 15 to 17.5%. At 56 days of the test, the leaching rate decreases exponentially to values of 3.45E-05 to 9.62E-06 g/сm²day. Characteristic of compounds, magnetite and zeolite up to 5% and radioactive waste 17.5%.

Abstract: Zeolites being used as builders in detergents are synthesized from expensive chemicals with a cumbersome production process. In this study, zeolite was synthesized from cheaper and readily available kaolin for possible use in detergent production. Kaolin from two sources namely Ajebo, Ogun State and Darazo, Bauchi State, Nigeria was used as starting materials while wet beneficiation followed by acid leaching was used to purify the kaolin and hydrothermal process was used to synthesize the zeolite. The chemical analysis confirms the presence of silica and alumina which are the precursors materials for zeolite synthesis. An increase in the amounts of the desired silica and alumina for both kaolin accompanied by a reduction in the amounts of the undesired oxides present in the kaolin as impurities are clear indications that the acid leaching was successful. The zeolites synthesized from both kaolin shows better water adsorption capacity and ion exchange capacity compared to those reported for zeolite synthesized from pure chemicals, this ability makes zeolite more suitable for the production of detergent. These results are indications that zeolites synthesized from kaolin can serve as a possible replacement for the more expensive zeolite synthesized from chemicals used as builders in detergent production.

Abstract: A modified natural zeolite will be used as a catalyst in the isomerization process of glucose to fructose. It is modified by inserting Fe into its pores with the impregnation method so that the active site of the catalyst is formed as part of the isomerization process. This study aimed to make a catalyst from Fe-impregnated natural zeolite and determine its catalytic performance under various pH, temperature, and isomerization time conditions. The zeolite was activated using 6M H₂SO₄ and 0.5M KMnO₄. The zeolite impregnation process was carried out using 1% (%w/v) FeCl₃.6H₂O solution with a ratio of (1:8) and continued with calcination at 500°C for 4 hours. The Fe-zeolite catalyst was characterized to determine the degree of crystallinity and crystal form, functional groups of its constituent compounds, and surface area. The isomerization process was carried out as a substrate of 10% glucose solution and 1 g of Fe-zeolite catalyst at various temperatures of 40, 50, and 60°C; pH 5, 7, and 9; a sampling time of every 15 minutes for 1 hour. The best fructose yield from the isomerization process was at a reaction temperature of 60°C, pH 5, and 45 min with a yield of 0.837%. It concluded that the Fe-Zeolite catalyst did not give a significant effect on the glucose isomerization process. It is expected that other researchers conduct similar research with different types of metal impregnated to give better results on the glucose isomerization process.

Abstract: Artificial barriers are being considered for the burial disposal of low-level radioactive waste in Japan. The artificial barrier consists of i) a low permeable layer made of bentonite materials that suppresses migration of nuclides due to advection, and ii) a low diffusion layer that uses cementitious materials that suppresses migration of nuclides due to diffusion. In addition, as methods of disposing of radioactive waste generated by the accident at the Fukushima Daiichi Nuclear Power Station, controlled disposal and isolation-type disposal are being considered. We thought that it would be effective to add adsorption performance to the performance of suppressing migration of such radioactive substances. In this study, we designed and experimented on the adsorption performance of mortar mixed with various zeolites, which had never been examined. As evaluation methods, i) fluidity, ii) strength, iii) low diffusivity, and iv) distribution coefficient of cesium and iodine were obtained. Based on the results, we reexamined the composition and conducted experiments to examine the applicability to high-adsorption artificial barriers. As a result, it was confirmed that the mass transfer resistance tends to be low due to the zeolite being porous. It was also shown that the strength of mortar mixed with zeolite depends on the cement matrix. As a result of this research, the distribution coefficient of cesium in cementitious materials using zeolite with a high cation exchange capacity designed in this research is higher than that of cementitious materials for low-level radioactive waste disposal facilities currently in operation 1,500 times was obtained. On the other hand, we were able to discover the possibility of examining construction on a full-scale regarding fluidity and compressive strength. As a future task, it was found that it is necessary to investigate a more practical artificial barrier by increasing the strength and densification of the cement paste.

Abstract: Wastes from various industrial processes are used in the construction industry in the production of cement composites, for example as a replacement for part of the cement. In addition to contributing to promoting circularity and reducing the carbon footprint, several waste materials have properties that promote improved durability of the resulting composites due to their pozzolanic properties. This paper deals with testing of the pozzolanic activity of selected wastes from local manufacturing processes such as slag, zeolite, microsilica and fly ash using the thermal analysis method (TG/DSC). The highest pozzolanic activity after 2 days was observed for blast furnace slag, however, after 56 days it was recorded for fly ash and ladle slag. Blas furnace slag and microsilica showed very similar pozzolanic activities evaluated by a comparable amount of unreacted calcium oxide of about 35%.