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EN
Chromium is the main constituent of the tanning salts used by tanneries for processing skins into leather, and considered as a pollutant in the effluents that this industry discharge. The present study aimed to evaluate the removal of chromium and other pollutants in effluents from the tanning industry applying the natural zeolite Neonite. Neonite is a commercially available zeolite, which was acquired from NEONITE S.A. Neonite was characterized through FTIR and XRD, identifying clinoptilolite as its main component. Treatment was applied to the samples of real effluents from the tanning stage or chromium bath (CB) and a composite effluent (CE), an experimental design was carried out for each effluent. The designs correspond to 32 factorial designs, the variables tested were the Neonite dosage (NE) measured in g/L, stirring time (StT) expressed in minutes and the pH of the sample, and the response variable was the residual chromium content (RCC). Statistical analysis was performed through R-software version 4.2.3 and included Box-Cox transformation and ANOVA to determine the main effects and the behavior of the response variable in relation to the applied model and its optimization by response surface. In CB, a removal above 95% was obtained for RCC, with optimization values at 32 g/L of NE and pH 7. In the CE, a removal of more than 98% was obtained for RCC and values higher than 60% for BOD, COD, TSS and Fats, being the optimal conditions 4.73 g/L of NE and 12.17 minutes of StT. These results demonstrate that the application of Neonite for the removal of chromium and other pollutants from tanning industry effluents has a great potential.
PL
Przedstawiono wyniki badań selektywnego uwodornienia acetylenu w obecności katalizatorów zawierających pallad jako fazę aktywną. Jako nośniki zastosowano porowate matryce Al₂O₃ oraz mieszaniny Al₂O₃ i zeolitu Beta. W pracy zbadano także wpływ prekursora palladu, czyli kompleksów chlorkowych i azotanowych(III) palladu(II) na właściwości katalityczne otrzymanych materiałów. Badania katalityczne przeprowadzono w skali laboratoryjnej w reaktorze odzwierciedlającym proces przemysłowy. Najwyższą aktywność i selektywność katalizatora uzyskano w obecności katalizatora otrzymanego w wyniku adsorpcji kompleksów azotanowych(III) palladu(II) na nośniku Al₂O₃.
EN
Pd catalysts were obtained by impregnating chloride or nitrate(III) complexes of Pd(II) on Al₂O₃ or zeolite Beta or Al₂O₃ and zeolite Beta mixt. as supports. In a laboratory installation simulating an industrial process, catalytic tests were carried out in the reaction of selective hydrogenation of acetylene at a concn. of 4% vol. in ethylene. The highest activity and selectivity were achieved in the presence of a catalyst obtained by adsorption of Pd nitrate(III) complexes on an Al₂O₃ support.
PL
Porównano zależności przyczepność-poślizg oraz mechanizmy zniszczenia dla betonu z dodatkami zeolitu i metakaolinitu w obecności prętów GFRP, BFRP i stalowych. Przyczepność prętów GFRP do betonu z dodatkiem metakaolinitu była o 50% większa niż do betonu zwykłego, natomiast przyczepność do betonu z zeolitem podobna. W przypadku prętów BFRP stwierdzono wzrost przyczepności o 7% dla betonu z metakaolinitem. Pręty BFRP miały większą przyczepność w stosunku do zbrojenia stalowego. Zmiana przyczepności prętów GFRP i BFRP była stopniowa, a poślizg był kilkukrotnie większy niż prętów stalowych.
EN
Bond stress-slip relationship and failure mechanisms for concrete with additions of zeolite and metakaolin in the presence of GFRP, BFRP and steel bars were compared. The bond strength of GFRP bars to concrete with the addition of metakaolin was 50% higher than to ordinary concrete, while the bond strength to concrete with zeolite was similar. In the case of BFRP bars, an increase in bond strength by 7% was found for concrete with metakaolin. BFRP bars had greater bond strength to steel reinforcement. The change in the bond stress of the GFRP and BFRP bars was gradual and the slip was several times greater than that of the steel bars.
4
Content available remote Wpływ metakaolinitu i zeolitu na przyczepność prętów BFRP i GFRP do betonu
PL
Celem przeprowadzonych badań jest ustalenie, w jaki sposób obecność metakaolinitu i zeolitu wpływa na przyczepność prętów zbrojeniowych do betonu oraz na jego wybrane właściwości mechaniczne. Próbki do badań przygotowano zgodnie z obowiązującą procedurą testu belkowego wg [1]. Otrzymane wyniki pozwoliły na analizę porównawczą próbek referencyjnych oraz zawierających metakaolinit i zeolit. Badania wykazały, że wprowadzenie do betonu aktywnego dodatku pucolanowego w postaci metakaolinitu i zeolitu powoduje zwiększenie wartości naprężeń przyczepności o ok. 20% w przypadku prętów szklanych GFRP i 15% bazaltowych BFRP, przede wszystkim w fazie zniszczenia.
EN
The aim of the conducted research is to determine how the presence of metakaolinite and zeolite affects the adhesion of reinforcing bars to concrete and selected mechanical properties. Test samples were prepared in accordance with the applicable beam test procedure according to [1]. The obtained results allowed for a comparative analysis of the reference samples and those with metakaolinite and zeolite. The research showed that the introduction of an active pozzolanic additive in the form of metakaolinite and zeolite into concrete leads to an improvement in adhesion stress values of approximately 20% for GFRP glass bars and 15% for BFRP basalt bars, especially during the failure phase.
5
Content available remote Zeolites as catalysts: a review of the recent developments
EN
The article presents the latest solutions (period 2015-2023) regarding zeolites and zeolitic materials used as catalysts for chemical reactions. The use of zeolites, among others, was presented and discussed for the purification of gases and sewage, as a raw material for the production of cement, as a component of dressings for hard-to-heal wounds, for blood purification, for the purpose of controlled release of drugs, as molecular sieves, or for the protection of monuments. The use of zeolites as catalysts and the trends in their use for this purpose are discussed with particular emphasis.
EN
This paper provides an overview of the adsorption of petroleum products, focusing on various aspects such as adsorbent types, mechanisms of adsorption, factors influencing efficiency, kinetics, equilibrium, practical applications, and environmental implications. It explores the properties and characteristics of adsorbents, including activated carbon, zeolites, clay minerals, silica gel, and others, highlighting their interaction with petroleum products. The article delves into the theories and mechanisms governing the adsorption process, discussing physical and chemical adsorption as well as the role of forces like van der Waals, hydrogen bonding, and electrostatic interactions. The results of experimental investigations were conducted to evaluate the adsorption capacities of various adsorbents for petroleum products. The adsorption performance, kinetics, and equilibrium behavior of different adsorbents were analyzed, providing insights into their effectiveness in removing petroleum contaminants from aqueous solutions. The adsorption kinetics and equilibrium studies were explored through mathematical models like Langmuir and Freundlich isotherms. The practical applications of adsorption in the petroleum industry were discussed, including removing pollutants from wastewater, gas and diesel purification, and desulfurization. The environmental implications of adsorption technology in mitigating oil spills and reducing petroleum-related pollution were addressed. The conclusion emphasizes the significance of these studies in enhancing understanding, developing efficient solutions, and addressing environmental challenges associated with the petroleum industry. Ongoing research in this field aims to further improve adsorption processes for a more effective and sustainable approach.
EN
Metals pollution is often found in the immediate or neighboring areas of industrial or agricultural activities. This situation may significantly affect the environment, such as water, soil, and air pollution. Electrokinetic (EK) treatment is known to have higher efficiency for metals contaminated soil. However, the use of EK treatment is not widely as expected. This study employs EK treatment with different permeable reactive barriers and flushing solutions to remove Cd and Pb from agricultural soil. Soil pH, temperature, water content, electroosmotic flow, electric current, and metal concentration are calculated as responses to the EK treatment. Results showed that the EK treatments were effectively removed the metals from the contaminated soil. On the fifth day of the treatment, EK, which used activated carbon as PRB and citric acid as the chelating agent, removed a significant amount of Cd from the soil. Besides, the treatment using zeolite as PRB and citric agent as chelate can remove more than 90% of Pb after the sixth day of treatment. These results showed that PRB and chelating agents could effectively remove the metals from the contaminated soils.
PL
W pracy badano zaprawy naprawcze ze sztucznymi i naturalnymi dodatkami pucolanowymi do renowacji obiektów zabytkowych. Do zapraw wapiennych wprowadzono sztuczną pucolanę - popiół lotny wapienny klasy C oraz pucolanę naturalną w postaci zeolitu. Do przygotowania zapraw wykorzystano dwa różne rodzaje kruszyw: naturalny piasek rzeczny i cegłę łamaną. Łącznie wyprodukowano 18 zapraw, z czego dwie były zaprawami odniesienia. W pierwszej grupie zapraw badano popiół lotny będący główną pucolaną, w zaprawach z obu rodzajami kruszywa przy 20%, 40% i 60% zastąpieniu wapna popiołem. W drugiej serii zapraw jako zamiennika wapna zastosowano popiół lotny i zeolit w różnych proporcjach. W zaprawie odniesienia zastosowano samo wapno powietrzne. Po 28, 56 i 90 dniach dojrzewania zapraw oznaczono właściwości mechaniczne, fizyczne i skład fazowy. Porównując zaprawy z dodatkiem pucolany z zaprawami odniesienia, zauważono, że pucolany zapewniają znaczną poprawę właściwości fizycznych i mechanicznych zapraw naprawczych. O ile zaobserwowano znaczną poprawę właściwości fizycznych zapraw, w których jako jedyną pucolanę zastosowano popiół lotny, to właściwości mechaniczne były lepsze w zaprawach z zeolitem.
EN
In this study, repair mortars with artificial and natural pozzolan additives were produced for the restoration of historical buildings. Class C fly ash, an artificial pozzolan and zeolite the natural pozzolan, were substituted into these lime-based mortars. Two different aggregate types were used in the preparation of the mortars: natural river sand and crushed brick. A total of 18 batches of mortars were produced, two of which were reference batches. In the first group of batches, fly ash, which is the major pozzolan, was tested in both aggregate groups in 20%, 40%, and 60% ratios of lime substitution. In the second group of batches, fly ash and zeolite were used in different proportions as lime substitution. In the reference series, air lime was used alone. At the end of the 28, 56, and 90 days curing period, mechanical, physical properties, and phase composition of the mortars were determined. When the pozzolan-added mortars were compared with the reference mortars, it was observed that pozzolans provided significant improvements in the physical and mechanical properties of the repair mortars. While significant improvements were observed in the physical properties of the mortars where fly ash was used as the only pozzolan, mechanical properties were better in the mortars with zeolite.
EN
Zeolite has been successfully synthesized from clay and rice husk ash in the form of powder by using the hydrothermal method with variations in chemical compositions of alkaline solution and the amount of rice husk ash. The clay raw material was obtained from the Sidrap area of South Sulawesi and rice husk ash is obtained from the burning pile of rice husks. Sidrap clay and rice husk ash were activated using an alkaline solution of NaOH and varied rice husk ash and the addition of AlCl3. The addition of AlCl3, an alkaline solution of NaOH and H2O was used in the amount of 25.5 grams and variations of rice husk ash were 2.5 grams and 6.5 grams. Meanwhile, without the addition of AlCl3, an alkaline solution of NaOH and H2O was used for 20.5 grams and variations of rice husk ash from 2.5 grams and 6.5 grams. Then the mixture was then put into an autoclave with a temperature of 100°C for 3 hours. The basic material used in the manufacture of zeolite is carried out by X-ray Fluorescence (XRF) characterization to determine the constituent elements of basic material, which showed the content of SiO2 was 45.80 wt% in the clay and 93.40% in the rice husk ash. The crystalline structure of the zeolite formed was characterized by X-Ray Diffraction (XRD). It was found the resulting zeolite were identified as Zeolite-Y, Hydrosodalite, and ZSM-5. The microstructure properties of the resulting zeolite were determined by using Scanning Electron Microscopy (SEM).
EN
Effectiveness of selected chemical admixtures and mineral additives to mitigate alkali-silica reaction was compared based on reactive gravel aggregate. Lithium compounds in the form of nitrate and lithium polysilicate were used as chemical admixtures. Natural pozzolans containing zeolite were used as mineral additive. Efficiency of the additive was enhanced by modification with ammonium ions. Linear changes of mortars with crushed gravel aggregates were studied with the accelerated and long-term methods. Additionally, scanning electron microscopy was used for microstructural observations. It was demonstrated that at elevated temperatures the application of lithium compounds provided better protection. Under conditions similar to those in the field, 20-30% of natural pozzolans proved to be more effective in inhibiting the expansion. Regardless of the method of protection applied, the presence of alkali-silica reaction products was detected in the microstructure of the mortars.
PL
Na przykładzie reaktywnego kruszywa żwirowego porównano efektywność ograniczenia reakcji alkalia-kruszywo przy pomocy wybranych domieszek chemicznych i dodatków mineralnych. Jako domieszki chemiczne zastosowano związki litu w postaci azotanu i polikrzemianu litu. W przypadku dodatków mineralnych zastosowano naturalną pucolanę, zawierającą zeolit, której efektywność zwiększano poprzez modyfikację jonami amonowymi. Wykonano badania zmian liniowych zapraw z rozdrobnionym kruszywem żwirowym metodą przyspieszoną i długoterminową. Dodatkowo wykonano obserwacje mikrostruktury z wykorzystaniem elektronowego mikroskopu skaningowego. Wykazano, że w warunkach podwyższonej temperatury lepsze zabezpieczenie uzyskano po zastosowaniu związków litu. W warunkach zbliżonych do eksploatacyjnych zastosowanie 20-30% pucolany naturalnej skuteczniej hamowało ekspansję zapraw z kruszywem reaktywnym. Niezależnie od sposobu zabezpieczenia, w mikrostrukturze zapraw wykryto obecność produktów reakcji alkalia-krzemionka.
PL
W artykule zaprezentowano wyniki badań niskociśnieniowej adsorpcji gazowej błękitu pruskiego z użyciem N2 jako adsorbatu w celu określenia parametrów strukturalnych oraz CO2 w celu określenia parametrów sorpcyjnych. Zgodnie z danymi literaturowymi błękit pruski pod względem adsorpcji kationów porównywany jest do zeolitów, a jego struktura krystaliczna do MOFów. Z uwagi na ten fakt przeprowadzono badania porównawcze, wyznaczając parametry strukturalne zeolitu SN oraz MOFa MIL-140. Powierzchnia właściwa modelu adsorpcji wielowarstwowej BET dla błękitu pruskiego dla zoptymalizowanej temperatury odgazowania osiągnęła wartość 85,02 m2/g, przy całkowitej pojemności sorpcyjnej BET 19,53 cm3/g, co pozwoliło na uszeregowanie go jako sorbentu pomiędzy zeolitem a MOFem. Otrzymane wyniki porównano także z pracami innych autorów.
EN
This paper presents the results of a low-pressure gas adsorption study of Prussian blue using N2 as adsorbate to determine structural parameters and CO2 to determine sorption parameters. According to the literature, Prussian blue is compared to zeolites in terms of cation adsorption, and its crystal structure to MOFs. In view of this fact, a comparative study was carried out, determining the structural parameters of zeolite SN and MOF MIL-140. The specific surface area of the BET multilayer adsorption model for Prussian blue for the optimized degassing temperature reached 85.02 m2, with a total sorption capacity (BET) of 19.53 cm3/g, which allowed it to be ranked as a sorbent between zeolite and MOF. The obtained results were also compared with the works of other authors.
EN
The production wastewater contains phenol from the Non-Destructive Testing (NDT) unit because it uses solvents; meanwhile, the manganese originates from the metal material washing process. On the basis of laboratory test results, the wastewater originating from the NDT unit of Y Industry, resulted in a phenol level of 2.33 mg/L, exceeding the quality standard of 0.5 mg/L and manganese level of 14.13 mg/L that exceeded the quality standard of 2 mg/L, based on the Regulation of the Minister of the Environment Number 5 of 2014 concerning Wastewater Quality Standards. This research used the pretest-posttest experimental research design without control. The sample in this study was wastewater from the NDT unit of the Y Industry. The average phenol level after passing through the adsorbent media at a thickness of 40 cm, 60 cm, and 80 cm resulted in 0.99 mg/L with 63% reduction, 0.60 mg/L with 77% reduction, and 0,28 mg/L with 89% reduction, respectively. The average manganese level after passing through the adsorbent media at a thickness of 40 cm, 60 cm, and 80 cm resulted in 0.10 mg/L with 61% reduction, 0.06 mg/L with 76% reduction, and 0,05 mg/L with 80% reduction, respectively. The most effective thickness variation in reducing the phenol and manganese levels of NDT wastewater is 80 cm thickness.
EN
This paper presents the results of a cost-effectiveness analysis and a cost-benefit analysis for the production of X-type zeolites from fly ash. Positive results of the laboratory tests on the quality of zeolites derived from fly ash initiated a cost analysis on the production of this materials on an industrial scale. The cost-effectiveness analysis was conducted using the dynamic generation cost indicator (DGC ). The calculated DGC expresses the technical manufacturing cost of 1 Mg of synthetic zeolites. Whereas the cost-benefit analysis (CBA) was completed using the economic net present value (ENP V) and the economic internal rate of return (EIRR ) indicators. The calculated unit technical cost of producing 1 Mg of zeolites using an installation consisting of five reactors with a capacity of 25 m3 each is 211 EUR and is lower than the current market price of this product, including transportation costs. This proves the financial viability of the investment. The calculations of the economic efficiency of the installation (CBA method) show that it is fully economically viable to operate and use the products from a social point of view.
PL
W artykule zostały przedstawione wyniki oceny efektywności kosztowej i ekonomicznej produkcji zeolitów typu X z popiołów lotnych. Pozytywne wyniki badań laboratoryjnych dotyczące jakości materiału zeolitowego otrzymanego z popiołów lotnych były podstawą do przeprowadzenia oceny kosztów ich produkcji w skali przemysłowej. Ocenę efektywności kosztowej przeprowadzono przy wykorzystaniu dynamicznego kosztu jednostkowego (DGC ). Obliczony wskaźnik DGC wyraża techniczny koszt produkcji 1 Mg zeolitów syntetycznych. Natomiast analiza kosztów i korzyści (CBA) polegała na obliczeniu ekonomicznej bieżącej wartości netto (ENP V) i ekonomicznej wewnętrznej stopy zwrotu (EIRR). Obliczony jednostkowy techniczny koszt wyprodukowania 1 Mg zeolitów na instalacji składającej się z 5 reaktorów o pojemności 25 m3 każdy wynosi 211 EUR i jest niższy od ceny rynkowej tego produktu, wliczając koszty transportu. Świadczy to o opłacalności finansowej inwestycji. Przeprowadzone obliczenia efektywności ekonomicznej instalacji (metodą CBA) potwierdzają w pełni opłacalność jej eksploatacji i wykorzystania produktów z punktu widzenia społecznego.
14
Content available remote Wpływ zeolitu syntetycznego na syntezę tobermorytu
PL
W artykule przedstawiono wyniki badań wpływu dodatku zeolitu syntetycznego na powstawanie tobermorytu w mieszaninie tlenku wapnia z kwarcem. Zeolit syntetyczny otrzymano przez termiczną aktywację haloizytu, a następnie gotowaniu w roztworze wodorotlenku sodu. W pracy badano powstawanie tobermorytu przy stałym stosunku molowym CaO/SiO2 wynoszącym 0,86 w warunkach autoklawizacji odpowiadających ciśnieniu nasyconej pary wodnej w temperaturze 180ºC. Czas syntezy wynosił 4 i 12 godzin. Zeolit syntetyczny dodawany był w ilości 5%, 15% oraz 30% masy suchych składników. Badania wykazały, że zeolit syntetyczny wpływa na powstawania uwodnionych krzemianów wapnia o małym uporządkowaniu struktury. Po 4 godzinach autoklawizacji na dyfraktogramie próbek z dodatkiem zeolitu syntetycznego notuje się niewielki refleks tobermorytu. W próbkach, w których został przekroczony stosunek molowy Al/(Al+Si) > 0.15 pojawiają się hydrogranaty z grupy hibschit-katoit. W pracy wykazano, że hydrogranaty z grupy hibschit-katoit pojawiają się w próbkach z dodatkiem 15% oraz 30% zeolitu po 4 godzinach obróbki hydrotermalnej. Intensywność refleksu katoitu zmniejsza się wraz z wydłużeniem czasu autoklawizacji i zanika dla próbki z 15% zeolitu po 12 godzinach autoklawizacji. Dla tych próbek wykazano również obecność portlandytu.
EN
This paper presents the results of a study of the effect of synthetic zeolite addition on the formation of tobermorite in a burnt lime-quartz mixture. Synthetic zeolite was obtained by thermal activation of halloysite followed by boiling in sodium hydroxide solution. In this study, the formation of tobermorite was investigated at a constant CaO/SiO2 molar ratio of 0.86 under autoclaving conditions corresponding to saturated steam pressure at 180ºC. The synthesis times were 4 and 12 hours. Synthetic zeolite was added at 5%, 15% and 30%. Studies have shown that synthetic zeolite influences the formation of hydrated calcium silicates with poor crystallinity. After 4 hours of autoclaving for samples with synthetic zeolite, a small peak of tobermorite can be found on the XRD pattern. In samples where the molar ratio of Al/(Al+Si) > 0.15 was exceeded, hydrogarnets of the hibschite-katoite group appear. The paper shows that hydrogarnets of the hibschite-katoite group appear for samples with 15% and 30% zeolite after 4 hours of hydrothermal treatment. The intensity of the katoite reflection decreases with increasing autoclaving time and disappears for the sample with 15% zeolite after 12 hours of autoclaving. The presence of portlandite was also demonstrated in these samples.
EN
Zeolites, minerals with the formula Mx/n[AlO2]x(SiO2)y] zH2O, are environmentally friendly materials used as water treatment adsorbents, gas adsorbents, and petrochemical catalysts. This study used a mixture of aluminum black dross and waste glass to synthesize zeolites via a hydrothermal synthesis and analyzed the effects of varying reaction time on phase changes under different synthesis conditions. With increased reaction times, a phase change from zeolite Na-P1 to analcime was observed; on employing hydrothermal synthesis at 150°C for 96 h, the majority of the crystalline structures changed into analcime. Heavy metal cation adsorption was tested to assess the applicability of the synthesized analcime to water treatment. Zeolite adsorption of at least 95% was observed for both Pd and Cd ions. Although a higher level of adsorption was observed for Pb ion than Cd ion, Cd ion was demonstrated to undergo relatively faster adsorption when tested under optimal pulp density at the same level of adsorption (95%).
EN
The paper presents the application of the casting method for the production of porous composites, called syntactic foams, of the casting alloy - solid particles type. This method was used to produce composites based on Al alloys reinforced with particles of clinoptilolite, a natural mineral from the zeolite group. Before the casting process, tests were carried out on the morphology, physicochemical properties and chemical composition of the zeolite, which was obtained from a rock called zeolite tuff, mined in a quarry in Kucin, (VSK PRO-ZEO s.r.o., Slovakia). Observations of the microstructure of the produced composites were also carried out using a scanning electron microscope. Diffractometric tests of zeolite rock as delivered for research and of the produced samples reinforced with zeolite particles were also carried out. Initial studies of the density and porosity of the produced composites were performed. The usefulness of the presented method of composite production was assessed on the basis of the conducted structural tests, with particular emphasis on the particle distribution in the alloy matrix.
EN
In this work, nickel adsorption onto low Jordanian zeolite dose is being investigated. Natural zeolite doses were stirred continuously with nickel solutions in batch reactors at 180 RPM for 24 hours, where the temperature was set to 20°C. The pH was initially 4.5 and reached 5.2 at equilibrium. The removal efficiency of nickel reaches maximum value when the initial nickel concentration is around 1 ppm and then tends to decrease when the initial nickel concentration increases above 1 ppm. The optimal nickel removal reaches 65% when the initial nickel concentration is 1 ppm and the zeolite dose is 26 mg∙dm–3. This study investigates the behaviour of nickel removal and modelling isotherms below and above this critical peak point. At this level of zeolite dose, the adsorption does not follow either Freundlich or Langmuir isotherms, but rather, it follows Freundlich for the data plot just below the peak point with the highest coefficient of determination (R2) equals (0.98) when the zeolite dose is (26 mg∙dm–3), whereas it follows Langmuir for the data plot just above the peak point with the highest coefficient of determination (R2) equals (0.99) when the zeolite dose is (10 mg∙dm–3). These findings clarify the theory behind each isotherm and can be used to find new information for efficient treatment techniques.
EN
The paper presents the results of hydrothermal zeolitization of fly ash from hard coal combustion in one of the Polish power plants and possible further applications of zeolites. The synthesis was carried out using various NaOH fly ash mass ratio and the effect of NaOH concentration in the activating solution on composition of synthesized sample was tested. The present work proves the benefits from development of fly ash utilization and further opportunities in the use of zeolites. There exist the need for research to expand options to reduce harmful impact derived from energy production.
EN
The objective of this research was to produce safe water for shrimp by using zeolite as adsorbent to absorb unwanted substances (NH3 and H2S). In particular, this study also aimed to design the shrimp pond water treatment equipment, effect of flow rate on zeolite ability to absorb toxic gases (NH3 and H2S), and rate of absorption (K) and reaction (k). The adsorbent is zeolite which has adsorption properties, high surface area and pores suitable for water (3Å). Then, the concentration of ammonia, hydrogen sulfide was analyzed using Ammonia Test Kit and Hydrogen Sulphide of Hach Hydrogen Sulfide Test Kit. The materials used in this study were zeolite of Malang (East Java, Indonesia) and shrimp pond water. The best result of NH3 and H2S adsorption obtained at a flow rate of 3 L•min-1. The best adsorption constant value (K) achieved by a flow rate of 3 L•min-1. On the basis of the best value of R2, NH3 and H2S adsorption, it can be classified in the first-order kinetic model with R2 of 0.9763 and a k value of 0.0007 hours-1 with a flow rate of 6 L•min-1. From the data above, it can be calculated that the adsorbent needed in the adsorption of NH3 and H2S in a scale shrimp pond requires 18 kg of Malang zeolite with a column height of 3.62 m of adsorbent, a diameter of 2.07 m, and a column volume of 12.21 m3.
EN
The applicability of the natural and MnO2-coated zeolite as sorbent for the removal of Mn(II) from synthetic solutions has been investigated. Batch experiments were carried out to determine the influence of pH and Mn(II) concentration on the sorption process. A maximum removal efficiency (98.9%) was observed for modified zeolite with the concentration of 10 mg/dm3 of manganese in solution. The equilibrium data showed a very good correlation for both Langmuir and Freundlich sorption models and this suggests both monolayer adsorption and a heterogeneous surface existence. Maximum sorption capacity calculated from the Langmuir model constituted 5.57 mg/g for natural zeolite and 13.41 mg/g for modified zeolite.
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