Papers by Keyword: Zeolite

Abstract: This work aims to reveal the effects of zeolite on properties of fly ash based geopolymer under high temperature at 300 °C, 600 °C and 900 °C. The specimens were prepared by alkali activation of fly ash, which was partially replaced by two different types of zeolite at 10%, 20% and 30% by weight. The specimens were analyzed for the maximum compressive strength, weight loss percentage, XRD and SEM. The results highlighted that the percentage of weight loss increased with the ratio of zeolite replacement. The compressive strength of geopolymer with synthetic zeolite and natural zeolite at 7, 28, 60 days were similar. The high-temperature exposure resulted in the reduction in compressive strength in all proportions. At the same temperature, compressive strength of all specimens were not significantly different.

Abstract: The nitrification process inside the water treatment facilities is an environmental threat because it might cause unacceptable concentrations of nitrites in drinking water. Special data processing has been carried out in the course of daily monitoring of concentration levels for ammonium, nitrogen, nitrites, and nitrates in the Siverskyi Donets river at the water intake site, and downstream, in the water mass having passed through the facilities of the water treatment complex "Donets". Based on the above studies, a positive correlation was revealed (with a correlation coefficient of 0.64-0.93) between the activity of nitrification processes in the natural reservoir and the activity of nitrification inside the water treatment facilities. The environmental outcomes of the nitrification processes inside the water treatment facilities might be dangerous. Experimental studies have proven that the zeolite backfill of the rapid filters installed at the water treatment complex is the most favorable medium for immobilization of the nitrifying bacteria in comparison with other backfills of silica sand or anthracite coal, therefore it is quite suitable for the development of nitrification process. The studies have shown that nitrites do not accumulate in water after water treatment procedures, therefore, the rate of phase I nitrification inside these facilities does not exceed the rate of the second phase. To clean the filtering backfill of these microorganisms, a conventional technological wash is fairly enough.

Abstract: Effect of content of synthetic aluminosilicates in medium-density polyethylene on the fire hazard characteristics and mechanical properties of compositions is investigated. It has been shown that during decomposition of the filler with the release of water, its effectiveness depends not only on the endothermic effect of decomposition and the content of dehydration products, but also on the correspondence of temperature of the dehydration of the filler and the temperature of intensive decomposition of the polymer. Regardless of the type of fillers, an increase in their content in polymer composite material helps to reduce combustibility. It has been shown that compositions based on epoxy oligomers or medium-density polyethylene and synthetic zeolite have properties of self-extinguish and fairly high physical and mechanical characteristics. It is shown that epoxy polymer composite material with the content of inorganic fillers 40-70 wt.% can be used for sealing building structures and other products operating at elevated temperatures, as well as in a mode where the fire resistance and heat resistance of the sealing compound are decisive. A number of efficiency of flame-suppressing of fillers is presented. Formulations of compositions based on epoxy oligomers or medium-density polyethylene whith synthetic zeolite having an optimal ratio of fire hazard and mechanical properties and not having toxic or carcinogenic effects when heated are recommended.

Abstract: Ion removal is a long problem on natural freshwater resources. In order to modify the adsorption performance to remove ions from standard iron solution, natural zeolite and natural perlite were treated with deionized water (DI water) as D-zeolite and D-perlite. And, 1M sulphuric acid (H₂SO₄) was used to treat the adsorbent as H-zeolite and H-perlite. The capability of ion removal was preliminarily investigated from the reduction of iron in solution by X-ray fluorescence spectrometer. The result showed that treatment of adsorbents with DI water was more capability than 1M H₂SO₄ solution.

Abstract: Plastic pollution is an environmental problem that has not resolved until now. Pyrolysis is able to be a solution to reduce plastic waste. The use of catalysts will reduce heating temperatures, speed up processing time, and increase product yield. Natural zeolite has the potency as a catalyst in pyrolysis process due to its micropore structure, high acidity and thermal stability. The purpose of this research is to determine the effect of active zeolite catalyst on the polypropylene pyrolysis. The main process of this study is pyrolysis of polypropylene (PP) plastic waste without catalysts and with natural zeolite catalysts which were non-activated and activated. Natural zeolites were activated by HF, HCl and NH₄Cl. The well result of this research is represented by the yield, viscosity, calorific value, FTIR and GC-MS analysis. Based on the results of diffractogram analysis, natural zeolites catalyst in this study is included in modernite minerals crystalline. The ratio of Si/Al in zeolite before activation was 7.07 and the acidity was 0.697 g/mmol. After the activation process, the ratio of Si/Al and zeolite acidity increased by 62.181% and 43.84%. The use of active natural zeolite catalysts in pyrolysis PP could reduce the total reaction time by 57.14%. Pyrolysis products with active zeolite catalyst compared to without catalysts had clearer color and higher heating value, compared to pirolysis without catalyst. Based on function group analysis with FTIR, the mixture of hydrolyzed compounds containing successive functional groups are-C-H (alkanes), double bond of C=C, hydroxyl-OH group which can be determined as phenol (ArOH), alcohol (ROH), and carboxylic acid (RCOOH). The GC-MS analysis showed that pyrolysis products are composed of a mixture of alkanes, cycloalkanes, alkenes, carboxylic acids with aromatic rings, and ketones. The pyrolysis products without catalysts consist of 5-11 (C5-C11) carbon atoms, whereas the range of carbon atoms of pyrolysis products with active zeolite catalysts was 6-24 (C6-C24).

Abstract: A ceramic membrane has been produced from a natural zeolite. A series of samples has been sintered at range temperature from room temperaure to 900°C. The influence of the sintering temperature on the specific surface area, pore diameter, and surface roughness has been investigated. It has been found that a decrease for value of the specific surface area and average pore diameter from 300°C to 900°C was attributed to a change of the crystalline structure of tridimite from partially to fully crystallized samples. The fabricated membrane has been used successfully to evaluate the separation performance during the treatment of coconut sap. The membranes have a steady state flux from 0.12 to 0.22 mL/min.cm² at an applied pressure of 1 bar.

Abstract: Plastics materials have been an integral part in people’s daily life due to their high elasticity, formability and lightweight characteristics which are suitable for many products. However, exponentially growth of plastics waste leads to heavy environmental problems due to the plastics nature which is not easily degradable. One of solution to alleviate environmental problems due to plastics waste is to use pyrolysis method to burn plastics waste and convert them into lighter hydrocarbon which can be used as a source of energy. In this final project, the addition of zeolite catalyst in pyrolysis process of Polypropylene plastic waste has been studied in the terms of energy activation. Isoconversional Friedman and Flynn-Wall-Ozawa methods were used. The results may suggest that the role of zeolite as catalyst is pronounced only in the early stage of pyrolysis process. Keywords: plastics waste, Polypropylene, Zeolite, Friedman, Flynn-Wall-Ozawa

Abstract: Limited reserves of conventional fossil fuels have led people to come up with alternative fuels. Biodiesel is one of the alternative fuels that mostly produced nowadays. Glycerol as byproduct of biodiesel production can be converted to acrolein trough dehydration reaction. Acrolein is an important intermediate for the production of chemicals product and also used for agricultures. Application of various catalyst in glycerol dehydration to acrolein has been reported. Zeolite is a micro-porous, alumino-silicate mineral that can be used as catalyst for this reaction. Geothermal solid waste contains silica that can be used as zeolite catalyst raw material. In this research, zeolite catalyst was synthesized from geothermal solid waste in hydrothermal reactor at 150°C for 8 hours. The catalyst product was characterized by EDX and showed that the zeolite catalyst was analcime type. BET characterization showed that this catalyst has mesoporous surface area. Catalyst application on glycerol dehydration was occurred in fixed-bed stainless steel reactor. This process produced liquid product and analysed by FT-IR. The FT-IR result showed that the liquid product contains acrolein. The variation amount of catalyst in dehydration process affect to the glycerol conversion. The increasing of catalyst amount enhanced glycerol conversion.

Abstract: The synthesis of CaO/zeolite nanocomposite as a highly active and effective adsorbent for patchouli oil purification has been developed. This research aims to improve the quality of patchouli oil by synthesizing CaO/zeolite nanocomposites using a solid-state mixing method. The used mass ratios of zeolite:CaO were 0:100, 20:80, 40:60, 60:40, 80:20 and 100:0 (w/w), then nanocomposites with various zeolite-to-CaO ratios were then calcined at various temperature of 300°C, 400°C and 500°C. The zeolite, CaO and nanocomposites were characterized by using the Fourier-transform infrared (FTIR), X-ray fluorescence spectrometer (XRF) and surface area analyzer (SAA). The nanocomposites were then applied to patchouli oil and the assessment results of physical and chemical properties of patchouli oil were determined according to Indonesian National Standard (SNI) 06-2385-2006. After patchouli oil purification using ZECA nanocomposite, the acid number decreased from 5.42 to 0.39 mg KOH/g oil, the patchouli alcohol (PA) content increased from 33.08 to 34.27% and the Fe level decreased from 1.39 to 0.31 ppm.

Abstract: In remote areas, most roads still use pavements that are very sensitive to climate change, especially those using clay pavements with high plasticity. In addition to the issue of cost, the difficulty of obtaining a proper source of material is another problem that has led to soaring prices for materials. In this regard, a study was conducted using local materials, namely zeolite as a stabilizing material added with waterglass as activating agent. The research began with samples of laterite soil and natural zeolite for XRD test (microstructure testing), and then testing for laterite soil’s index properties and engineering properties, namely Unconfined Compressive Strength and CBR value. The purpose of the test is to determine the correlation between the Unconfined Compressive Strength (UCS) and the soil bearing capacity (CBR) caused by adding zeolite as stabilizer material and waterglass as activator with increasing curing time. Laterite soils contain a brownish red iron oxide. The stabilizing material zeolite contains a crystalline mineral of alumina silicate SiO₂. While waterglass composed of sodium meta silicate. Stabilization carried out by mixing 4%, 8%, 12%, 16%, and 20% of zeolite with addition of 2% waterglass, percentage was measured based on soil dry weight. Specimens were tested at curing time of 0, 7, 14, and 28 days. The test result shows increasing UCS and CBR values with increasing percentage of zeolite. At mix of 20% zeolite and 2% waterglass, the unconfined compressive strength reaches 23.54 kg/cm2 with CBR value 58% at 28 days of curing time.