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EN
This paper presents the results of studies on the transformation of geraniol (GA) in the presence of the natural mineral bentonite. The paper determines the influence of temperature, catalyst content, and reaction time on the course of the process. In order to determine the most favorable process conditions, the catalytic tests were carried out without solvent and under atmospheric pressure. Three functions were chosen to determine the most favorable process conditions: GA conversion and the selectivities of the main products: linalool – LO and beta-pinene – BP. In addition, the paper optimize GA transformation process based on response surface methodology (RSM). The impact of the most relevant process indicators was presented. For all factors of the method, their effects on all primary parameters were determined in the form of second-degree polynomials, and such process conditions were determined to achieve their maximum.
EN
Composites based on PLA with the addition of 3, 6 and 10 wt% silica, hydroxyapatite and bentonite were obtained by twin-screw extrusion. Maleic anhydride grafted polyethylene was used to enhance interface interactions. The influence of the fillers used on the Charpy impact strength, Rockwell hardness, tensile properties and processing shrinkage was investigated. Test samples were obtained by 3D printing. The highest impact strength and hardness were obtained for the composite containing 10 wt% hydroxyapatite. PLA with 10 wt% hydroxyapatite and 3 wt% bentonite was used to obtain anatomical structures by 3D printing.
PL
Metodą dwuślimakowego wytłaczania otrzymano kompozyty na osnowie PLA z dodatkiem 3, 6 i 10% mas. krzemionki, hydroksyapatytu oraz bentonitu. W celu zwiększenia oddziaływań na granicy faz użyto polietylenu szczepionego bezwodnikiem maleinowym. Zbadano wpływ stosowanych napełniaczy na udarność Charpy’ego, twardość Rockwella, właściwości mechaniczne przy statycznym rozciąganiu oraz skurcz przetwórczy. Próbki do badań otrzymano za pomocą druku 3D. Największą udarność i twardość uzyskano w przypadku kompozytu zawierającego 10% mas. hydroksyapatytu. Do otrzymywania struktur anatomicznych metodą druku 3D zastosowano hybrydowy kompozyt PLA zawierający 10% mas. hydroksyapatytu i 3% mas. bentonitu.
EN
The influence of the bentonite content (1, 3, 5 wt%) on the mechanical properties of lightweight cotton (C), polyester (P) and polyester-cotton (P/C 50/50) fabrics was investigated. Starch was used as a water-insoluble binder for coating fabrics. Bentonite nanoparticles were obtained by repeated hydration, decantation and evaporation of the water dispersion. The bentonite particle size was determined by the XRD method using the Debye-Scherrer equation. The diffraction of the laser beam was used to determine particles size distribution. The addition of bentonite nanoclay significantly improved tensile strength (26-61% and 99–118% in the warp and weft direction, respectively) and tear strength (4‒13% and 5–24% in the wrap and weft direction, respectively) of coated fabrics. Their abrasion resistance has also slightly increased. The biggest changes were noted for the cotton fabric, the smallest for the polyester fabric, which may result from the low compatibility between starch and the polyester fabric.
PL
Zbadano wpływ zawartości bentonitu (1, 3, 5% mas.) na właściwości mechaniczne lekkich tkanin bawełnianych (C), poliestrowych (P) i poliestrowo-bawełnianych (P/C 50/50). Jako nie-rozpuszczalny w wodzie środek wiążący do powlekania tkanin zastosowano skrobię. Nanocząstki bentonitu otrzymywano poprzez kilkukrotną hydratację, dekantację i odparowanie dyspersji wodnej. Wielkość cząstek bentonitu oznaczono metodą XRD, stosując równanie Debye-Scherrera. Dyfrakcja wiązki laserowej posłużyła do określenia rozkładu wielkości cząstek. Zastosowanie nanoglinki bentonitowej wpłynęło na istotną poprawę wytrzymałości na rozciąganie (o 26‒61% w kierunku osnowy i 99‒118% w kierunku wątku) oraz rozdzieranie (4‒13% w kierunku osnowy i 5‒24% w kierunku wątku) powlekanych tkanin. Nieznacznie zwiększyła się również ich odporność na ścieranie. Największe zmiany zanotowano w przypadku tkaniny bawełnianej, najmniejsze dla tkaniny poliestrowej, co może wynikać z małej kompatybilności między skrobią a tkaniną poliestrową.
EN
The influence of low-temperature plasma modification of bentonite on the dynamic-mechanical properties and vulcanization of rubber mixtures was examined. EDX, FTIR and TGA analysis were used to evaluate the filler. IR spectra of modified bentonite indicate lower intensity of the bands associated with OH groups and water. TGA confirms a smaller weight loss of samples subjected to plasma treatment, which also proves a lower water content in the mineral, confirming the effectiveness of the plasma treatment used.
PL
Zbadano wpływ modyfikacji bentonitu plazmą niskotemperaturową na właściwości dy-namiczno-mechaniczne oraz wulkanizację mieszanek gumowych. Do oceny napełniacza zastosowano analizę EDX, FTIR i TGA. Widma IR modyfikowanego bentonitu wskazują na mniejszą intensywność pasm związanych z grupami OH i wodą. TGA potwierdza mniejszy ubytek masy próbek poddanych obróbce plazmowej, co również świadczy o mniejszej zawartości wody w minerale, potwierdzając sku¬teczność zastosowanej obróbki plazmowej.
EN
The representative of natural layered clays, bentonite, was modified according to two routes and tested as a new catalyst for selective catalytic reduction of nitrogen oxides with ammonia (NH3-SCR). The natural acid-activated clay was ion-exchanged with Na+ or remained in H-form and pillared with metal oxides. In order to limit the number of synthesis steps, iron as an active phase was introduced simultaneously with Al2O3 during the intercalation procedure. Additionally, the samples were doped with 0.5 wt% of copper to promote low-temperature activity. It was found that the performed modifications resulted in disorganization of the ordered layered arrangement of bentonite. Nevertheless, acid activation and pillaring improved structural and textural parameters. The results of catalytic tests indicated that the samples containing Fe2O3 pillars promoted with Cu exhibited the highest NO conversion of 85% at 250°C (H-Bent-AlFe-Cu) and 75% at 300°C (Na-Bent-AlFe-Cu). What is important, activity of the protonated samples in the high-temperature region was noticeably affected by the side reaction of ammonia oxidation, correlated with the production of NO and resulting in N2O emission during the process comparing to Na-Bentonite catalysts.
EN
Bentonite is the traditionally used binder in iron ore pelletization. However, it consists of up to 85% silica and alumina which are undesired acidic gangue in iron-making. In this study, carboxymethyl cellulose, sodium lignosulfonate and cornstarch were used as acidic gangue-free organic alternatives to bentonite in synthesizing iron pellets. Iron ore, water and the corresponding binder were mixed and rolled in a pelletizing disk to form green pellets. The green pellets were dried and subsequently indurated in a furnace at 1200 ℃ to form indurated pellets. To evaluate the effectiveness of the organic binders, the pellets produced were tested on various pellet properties. Known industrial pellet property standards and the bentonite binder were used as references. Carboxymethyl cellulose, sodium lignosulfonate and corn starch produced green pellets with average drop numbers of 7.20 ± 0.84, 5.60 ± 0.89 and 6.00 ± 1.00 respectively, compared to bentonite’s 5.00 ± 0.71. Dry pellets of average compressive strength 5.93 ± 0.09, 5.86 ± 0.03 and 11.52 ± 0.18 kg/pellet were produced by carboxymethyl cellulose, sodium lignosulfonate and corn starch respectively while bentonite’s averaged 5.60 ± 0.08 kg/pellet. For indurated pellets, carboxymethyl cellulose (210.2 ± 1.88 kg/pellet) and sodium lignosulfonate (198.1 ± 2.49 kg/pellet) pellets were weaker than those of bentonite (250.4 ± 2.06 kg/pellet) but satisfied the industrial requirement of 181.4 kg/pellet. A boron oxide additive (0.1 wt. %) was used to boost the strength of carboxymethyl cellulose indurated pellets to 252.6 ± 1.32 kg/pellet, rendering them superior to those of bentonite.
EN
To prevent the serious threat of textile wastewater, researchers have developed adsorption-based wastewater treatment using cheap, yet effective, adsorbent materials. Of which is natural bentonite, that has the advantages for adsorption due to its porous structure and functional groups but still suffers from its low affinity against anionic and hydrophilic azo dyes. Herein, we aimed of improving the affinity by amino acid tryptophan embedment into the locally isolated natural bentonite collected from Aceh Province, Indonesia. The prepared bentonite samples were characterized using Fourier transform infrared, X-ray diffraction, and scanning electron microscopy. Adsorptive removal was performed on naphthol blue black (NBB) in a batch system with variations of contact time, pH, and adsorbent dosage. The isotherm studies were carried out at optimum conditions (contact time=15 minutes; pH 1; adsorbent dosage=0.2 g) with several models including Langmuir, Freundlich, Sips, and Redlich-Peterson isotherm models. The characterization results revealed that the modification altered its functional group, crystallinity, and micro-surface morphology that add more benefits for adsorption. At optimum conditions, 99.2% NBB has been successfully removed from the aqueous solution. The isotherm studies suggested that the NBB adsorption onto the tryptophane-modified natural bentonite was dependent on Sips isotherm model (R2=0.999; root-mean-square-errors=1.11×10-4 mg/g).
EN
The objectives of this study are the thermal remediation of bentonite waste to convert non-hazardous material, and the use of the obtainedthermal recycling bentonite waste (TRBW) as a novel low-cost adsorbent for the removal of heavy metals from aqueous solution using the batch system. The origin of bentonite waste is a by-product from plants of spent engine oil recycling [PSEOR]. It was remediated in two stages, directly burning and in the electrical furnace at 700 °C for 100 minutes to eliminate oil residues and impurities. The tests of XRD, BET, FTIR, EDX, and SEM were accomplished to identify the chemical and physical characteristics of TRBW. After then, the examination of the ability of TRBW to adsorption of the fiveheavy metals (Zn, Ni, Cd, Cr, and Pb) with different experimental parameters such as initial concentration, adsorbent dose, temperature, pH, and contact time. Different models of isotherm, kinetic, and thermodynamic were utilized andthe results indicate that the nature of heavy metals adsorption onto TRBW was homogeneous. According to the maximum adsorption capacities, the metals ranked as Pb> Cd> Zn> Cr> Ni, and adsorption capacities were 94.97, 73.85, 39.56, 38.34, and 36.33 mg/g, respectively.
EN
The objective of the current work was to investigate the effectiveness and mechanism of nitrate removal from an aqueous solution by adsorption using metal (Zr4+)loaded chitosan and Bentonite beads (Cs-Bn-Zr). The study was carried out in a batch system, and the effect of the critical factors on the adsorption performance, such as contact time, initial nitrate anion concentration, and adsorbent dosage, were investigated. In addition, the adsorption equilibrium models of the Langmuir, Freundlich, and Temkin isotherms were evaluated. The modified adsorbent was characterized by Fourier transform infrared spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), and analysis with an energy-dispersive X-ray analyzer (EDX). The results demonstrated that at 0.2 g of CS-Bn-Zr adsorbent with an initial concentration of 50 mg/l and a contact time of 120 minutes, the maximum removal of nitrate ions was found to be 97.28%. The result demonstrated that the maximum adsorption capacity of nitrite ions on the manufactured bead was 110.46 mg/g. The Freundlich model was shown to be the most effective for the adsorbate of nitrate. The pseudo–first-order model fits the adsorption kinetic data well.
EN
In order to use alum in large numbers for the treatment of low turbidity water, a novel method has been used to treat low turbidity water using bentonite with a reduced amount of alum. Given that bentonite has a negative charge, it is added to the raw water to give the blocks weight. The weight is then added by joining the blocks together to create massive blocks that settle more quickly. In addition to providing a large surface for organic compound adsorption, it increases the suspension’s weight and particle density. There are between 10 and 50 mg/l of bentonite clay utilized.In the Karbala water treatment plant, the effectiveness of the water quality index (WQI) at turbidity 20NTU (national turbidity unit) using alum alone was subpar (71.16%). Under the same circumstances, the pilot plant’s WQI efficiency was equally low (72%). The turbidity of the water was increased to 120 NTUwhen bentonite was used in the pilot plant, increasing the efficiency of WQI to 97.2%. When bentonite was added to the water, the turbidity was increased to 200 NTU and the WQI efficiency was increased to 98.9%. The usage of bentonite produced a high level of WQI efficiency and a cheap substance free from infections or negative effects.
EN
This article examines the possibilities of improving the ecological condition of small rivers on the example of the upper part of the Prut River in the vicinity of Yaremche (Ivano-Frankivsk region, Ukraine). The previously published data of the article authors and other researchers that the amount of pollutants in river water in this area has increased, in particular, phosphorus compounds, has been confirmed. It was shown that the incompletely purified wastewaters of Yaremche, which contains an excess of phosphate ions, has a significant impact on this fact. On the basis of their own previous research and current work, the authors propose removing these ions using a natural sorbent based on bentonite, activated by microwaves in various ways. Experiments have shown that microwave activation of this sorbent increases the coefficient of phosphate ions extraction from wastewater significantly higher compared to natural bentonite. An approximate technological scheme of wastewater purification from excess phosphates after the main standard purifying cycle was suggested.
EN
Using the products derived from agricultural wastes as low-cost adsorbent materials to remove organic or inorganic contaminants would be ideal, as these materials are readily available in many countries. This study aimed to prepare environmentally friendly adsorbents made from nanocomposite OPBA / Bentonite / TiO2. The coprecipitation method was used in preparing OPBA, and CTAB surfactant was added in bentonite preparation. Meanwhile, the manufacture of TiO2 was carried out using the sol-gel method. Characterization was done by XRD, FTIR, SEM, and BET. The adsorbent spectra did not show a significant shift in absorption where the O-H bonds were becoming weaker due to the presence of TiO2 in the interlayer of bentonite. Another possibility is due to the influence of calcination and heating. The O-H groups of H2O are hydroxylated and dehydrated from within between layers. The formation of the composite OPBA/TiO2/Bentonite does not change the crystallinity of TiO2 significantly. This proves that there is no decrease in photocatalyst activity after the addition of OPBA and bentonite. The morphology of the whole sample has a flake-like structure that has pores. The addition of OPBA into Bentonite/TiO2 causes a decrease in the specific surface area of the sample.
EN
The ability to effectively use mineral resources is the key to the sustainable development of industry in modern conditions of environmental protection. High-quality bentonites are rarely found in nature, so technologies for improving the quality of clay powders are quite relevant today. The article considers the possibility of improving the quality of clays obtained from candidate quarries for the purpose of further use as components of drilling fluids. The filtration and rheological characteristics of drilling fluids obtained on the basis of activated clay powder were also investigated by Benta Limited Liability Company.
EN
Wastewater pollution with detergents is one of the environmental problems associated with the rational use of water resources. The existing methods of physicochemical wastewater treatment, despite their efficiency, are open to secondary environmental pollution. Biological coagulation/flocculation methods are widely used with the plant waste. The aim of this research was the use of ferric iron obtained by means of the bacterial-chemical method and bentonite to reduce the chemical oxygen demand in the wastewater containing detergents. It was identified that the use of Fe2 (SO4)3 obtained using the bacterial-chemical method with thionic bacteria Acidithiobacillus ferrooxidans BIT 1 and bentonite as a clay material is promising. At the same time, it was found that the highest reduction degree in the chemical oxygen demand – 88.1 ± 7.9% in wastewater was noted in the variation where the bacterial-chemical ferric iron in the amount of 1.75 g/L was used in combination with bentonite in the amount of 600 mg/L.
EN
Polycyclic aromatic hydrocarbons (PAHs) are introduced to the environment from anthropogenic and natural sources. The most significant natural source of PAH are wildfires and volcanic eruptions. The PAHs occurring in the soil mostly bind to the root system of plants. Phytodegradation, specifically rhizospheric degradation, can reduce the PAH levels in soil with the help of plants roots. A pot experiment was conducted to study the effect of application of soil amendments on the PAHs level in the burnt soil (BS). The aim of this study was to assess the effect of application of soil amendments (compost, biochar, and bentonite) on the PAHs level after performing experiment with two grass species (Lolium perenne, Festuca rubra). Biochar and compost turned out to be the most effective amendments, regardless of the used grass species. Phytomanaged BS without added amendments also demonstrated the potential for PAH dissipation, but only in the case of Festuca rubra. It has been proven that the application of soil amendments together with the test grass species induced important changes in the BS properties (alteration of soil pH with related change of Kow of individual PAHs; root system on which soil microorganisms thrive) which evoked an increased bioavailability of PAHs.
EN
The public concern over sediment contamination brought on by mining operations, excessive use of chemical fertilisers or pesticides, industrial, agricultural, and municipal effluent, is increasing. Dredging is a more expensive treatment option than in situ capping of polluted sediment for immobilising pollutants in sediments on site. In order to stop the release of Cr and Cu from chemically contaminated sediments, this study aimed to evaluate the efficiency of utilising active capping materials such as bentonite (B), kaolin (K), and a 1:1 combination of bentonite and kaolin (BK) as capping materials. In a 90-day laboratory experiment carried out in glass tanks with a 1 cm thickness cover of capped material plus sand spread over the polluted sediment, the efficacy of B, K, and BK in inhibiting trace metal leachability was examined. The findings demonstrated that B and BK decreased the ability of sediments to leach Cr and Cu. The results suggest that BK and B should be considered as a suitable active material for capping treatment of polluted sediment sites because of their high Cu and Cr trapping. According to an analysis of adsorption kinetics, chemisorption was the adsorption process. The outcomes of this study demonstrated the potential for using kaolin, a bentonite-kaolin clay mixture covered with sand, and bentonite as capping materials for the in-situ treatment of Cr and Cu polluted coastal sediments.
17
PL
W artykule scharakteryzowano bentonit, wymieniono obszary jego zastosowania oraz podano najważniejsze cechy. Przedstawia również zasady prawidłowej aplikacji materiałów bentonitowych.
EN
The article characterizes bentonite, lists the areas of its application and its most important features. The principles of proper application of bentonite materials were also provided.
PL
W pracy przedstawiono technologię otrzymywania silikonowych klejących taśm samoprzylepnych charakteryzujących się zwiększoną odpornością termiczną. Do otrzymania samoprzylepnych produktów wykorzystano komercyjne żywice silikonowe modyfikowane dodatkiem napełniacza (bentonitu) oraz związkiem sieciującym. Otrzymane taśmy przebadano pod względem właściwości użytkowych, takich jak adhezja, kohezja oraz kleistość, a także sprawdzono ich odporność termiczną, która średnio wzrosła o ok. 60%. Otrzymane nowe produkty samoprzylepne są w pełni transferowalne do przemysłu i mogą znaleźć zastosowanie np. w ciepłownictwie.
EN
Paper presents the technology of obtaining silicone self-adhesive tapes based on which exhibit increased thermal resistance. Commercial silicone resins modified with the addition of a filler (bentonite) and a cross-linking compound were used to obtain self-adhesive products. The obtained tapes were tested in terms of functional properties, such as adhesion, cohesion and tack, and their thermal resistance was checked, which on average increased by about 60%. The obtained new self-adhesive products are fully transferable to industry and can be used, for example, in heating.
PL
Zjawisko utrudnionej sedymentacji osadu czynnego może występować stale bądź okresowo. Ważne jest, aby odpowiednio zweryfikować przyczynę powstania problemu i wykorzystać dostępne na rynku narzędzia w celu szybkiej interwencji. Zastosowanie preparatu DuoBent pozwala skutecznie optymalizować procesy oczyszczania ścieków nawet w przypadku dużego napływu ścieków przemysłowych na oczyszczalnię.
EN
Today, foundries are facing increasing demands for greener and more economical production while maintaining or improving the quality of the castings produced. The importance and use of green sand mixtures using bentonite as a binder are thus coming to the fore once again. They have the advantage of both eliminating the chemicalization of production and also allowing the immediate use of the already used mixture, including the binder, after adjustment of the composition and mulling. In order to maintain the quality of the resulting castings, it is necessary to monitor the properties of the moulding mixture through a series of laboratory tests. It is also essential to look at the processing quality of these mixtures, i.e. the combination of good mulling quality and efficient mulling time, which is often neglected. It is the quality of mulling and the effective mulling time that help to develop the bonding properties of the bentonite, improve the properties of the mixture, determine the efficiency of the muller and possibly reduce the time and energy required for mulling. The aim of this work is to present the effect of mulling on the properties of sand-water-bentonite mixtures. The properties studied are mainly the compactability, strength characteristics, moisture content of the mixture and the order of addition of raw materials.
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