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In this work clinoptilolite nanoparticles were modified with conducting polyaniline by the polymerization of anilinium cations in and out side of the clinoptilolite channels and a nanocomposite of polyaniline/clinoptilolite was obtained. Cations (Na + , K + , Mg 2+ , Ca 2+ …) in the natural clinoptilolite structure were exchanged with anilinium cat...
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... of each other. Figures 3 to 5, respectively show the SEM images of clinoptilolite, polyaniline and PANI/ Clinoptilolite nanocomposite. The SEM image of clinoptilolite (Fig. 3) shows the layered structure of clinoptilolite with layer thicknesses in nanorange (<100 nm). The SEM image of Removal of Toxic Hexavalent Chromium S147 polyaniline (Fig. 4) shows its relatively amorphous structure. The SEM image of PANI/clinoptilolite nanocomposite (Fig. 5) shows the presence of polyaniline on the layered surface of clinoptilolite. This image shows that the formation of polyaniline takes place not only in the clinoptilolite channels, but also on the clinoptilolite out side surfaces. This ...
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... SEM was used to investigate the surface morphology of RGO, RGO-Ag, PANI, PANI@RGO.Ag nanocomposites [24][25][26][27][28][29]. The SEM micrograph of RGO revealed its transparent, paper-like appearance with a wrinkled surface, indicating successful exfoliation of the graphene sheets as shown in figure 3a [24]. ...
... These fibers seem to be closely packed, forming a network of interconnected strands that give the polymer a spongy appearance. The figure illustrates the relatively amorphous nature of polyaniline [25][26][27][28][29][30]. Silver nanoparticles are uniformly dispersed and visible on the surface of the transparent RGO sheet as shown in figure 3 (c). ...
... The Ag nanoparticles are notably and uniformly dispersed throughout the RGO matrix. In addition, the manner in which AgNPs are distributed within the RGO nanosheets signifies a robust interaction between them, thereby augmenting the electrical conductivity of the prepared RGO [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. Furthermore, figure 4(d) displays the TEM images of the PANI@RGO.Ag hybrid, providing a clear view of the synthesized electrode material's morphology. ...
... The microstructure of both types of zeolites is shown in the Fig. 2a and b. Clinoptilolite is characterized by a layered structure with a regular lamellar conglomerate 22 . Different microstructure had FCC. ...
The production of ordinary Portland cement (OPC) is one of the main global causes of CO2 release to the atmosphere. However, its availability and unique characteristics as a binding material make it difficult to be substituted by eco-friendlier materials. However, OPC partial replacement with pozzolanic materials is one of the best solutions to this problem. Hence, in this study, various types of high-volume zeolite were employed as supplementary cementitious materials (SCM), substituting the OPC by up to 50 wt.% in the composition of the created mortars. Besides, quicklime and inorganic accelerators were included in some of the mortar mixtures to improve the hydration reaction and enhance its speed. The mechanical, durability and durability in sea water properties were investigated. Although the usage of SCM caused a decrease in the mechanical and durability properties of the specimens, the addition of 10 wt.% quicklime palliated this degradation by enhancing by 40% the 28-days compressive strength of the specimens and by significantly improving their durability (porosity, freeze–thaw resistance and carbonation resistance). Moreover, the mixtures were proved to be resistance to aggressive ionic environments, since their compressive strength even increased after 28-day immersion in seawater, due to the additional formation of hydration compounds.
... Similarly, polyaniline-modified clinoptilolite manifested 98% Cr (VI) removal efficiency, and HDTMA-HSO 4 (hexadecyl-trimethyl-ammonium)-treated mordenite displayed 93% Cr (VI) adsorption potential (Campos et al. 2007;Olad et al. 2011). Likewise, rice husk-derived zeolite faujasite possessed 92% chromium elimination efficiency from an aqueous solution (Chanda et al. 2022). ...
Nanocomposites are emerging as a new generation of materials that can be used to combat water pollution. Zeolite-based nanocomposites consisting of combinations of metals, metal oxides, carbon materials, and polymers are particularly effective for separating and adsorbing multiple contaminants from water. This review presents the potential of zeolite-based nanocomposites for eliminating a range of toxic organic and inorganic substances, dyes, heavy metals, microplastics, and ammonia from water. The review emphasizes that nanocomposites offer enhanced mechanical, catalytic, adsorptive, and porosity properties necessary for sustainable water purification techniques compared to individual composite materials. The adsorption potential of several zeolite-metal/metal oxide/polymer-based composites for heavy metals, anionic/cationic dyes, microplastics, ammonia, and other organic contaminants ranges between approximately 81 and over 99%. However, zeolite substrates or zeolite-amended soil have limited benefits for hyperaccumulators, which have been utilized for phytoremediation. Further research is needed to evaluate the potential of zeolite-based composites for phytoremediation. Additionally, the development of nanocomposites with enhanced adsorption capacity would be necessary for more effective removal of pollutants.
Graphical Abstract
... Face mask sensor. Reference [35] is cited in Supplementary Materials. ...
The coronavirus disease (COVID-19) pandemic has increased pressure to develop low-cost, compact, user-friendly, and ubiquitous virus sensors for monitoring infection outbreaks in communities and preventing economic damage resulting from city lockdowns. As proof of concept, we developed a wearable paper-based virus sensor based on a molecular imprinting technique, using a conductive polyaniline (PANI) polymer to detect the lentivirus as a test sample. This sensor detected the lentivirus with a 4181 TU/mL detection limit in liquid and 0.33% to 2.90% detection efficiency in aerosols at distances ranging from 30 cm to 60 cm. For fabrication, a mixture of a PANI monomer solution and virus were polymerized together to form a conductive PANI sensing element on a polyethylene terephthalate (PET) paper substrate. The sensing element exhibited formation of virus recognition sites after the removal of the virus via ultrasound sonication. A dry measurement technique was established that showed aerosol virus detection by the molecularly imprinted sensors within 1.5 h of virus spraying. This was based on the mechanism via which dispensing virus droplets on the PANI sensing element induced hybridization of the virus and molecularly imprinted virus recognition templates in PANI, influencing the conductivity of the PANI film upon drying. Interestingly, the paper-based virus sensor was easily integrated with a wearable face mask for the detection of viruses in aerosols. Since the paper sensor with molecular imprinting of virus recognition sites showed excellent stability in dry conditions for long periods of time, unlike biological reagents, this wearable biosensor will offer an alternative approach to monitoring virus infections in communities.
... Modification of natural zeolites can make them suitable for sorption of anions and organic compounds. Using adhesion and polymerization processes, clinoptilolite tuffs were modified with polypropylene [5], polyhexamethylene guanidine [6], polyorganosiloxanes [7], chitosan [8], polyethylenimine [9], polypyrrole [10], polyaniline [11], siloxane-modified lignocellulose [12], and other polymers. Biodegradable polyvinyl alcohol (PVA), [-СН 2 -СН(ОН)-] n , is used in the composition of carbon sorbents [13]. ...
We have studied the effect of mechanical activation and modification with polyvinyl alcohol (PVA) on the composition, structure, and oil sorption capacity of zeolite (clinoptilolite and clinoptilolite-stilbite) rocks. The specific power of the vibratory attritor was 12 W/g, the specific mechanical energy delivered to the materials was 2.16 kJ/g, and the ball-to-powder weight ratio was 32 : 1. The materials were characterized by scanning electron microscopy, X-ray diffraction, infrared spectroscopy, differential scanning calorimetry, thermogravimetry, and low-temperature nitrogen adsorption measurements. The results demonstrate that modification of clinoptilolite-stilbite or clinoptilolite rocks with 20 wt % PVA raises their oil sorption capacity on solid surfaces by 15-18%.
... Модификация природных цеолитов может сделать их пригодными для сорбции анионов и органических соединений. С помощью адгезионного и полимеризационного способов клиноптилолитовые туфы модифицировали полипропиленом [5], полигексаметиленгуанидином [6], полиорганосилоксанами [7], хитозаном [8], полиэтиленимином [9], полипирролом [10], полианилином [11], лигноцеллюлозой, модифицированной силоксанами [12] и другими полимерами. Биоразлагаемый поливиниловый спирт (ПВС) -[-СН 2 -СН(ОН)-] n -применяют в составе углеродных сорбентов [13]. ...
Изучено влияние механоактивации и модификации поливиниловым спиртом (ПВС) цеолитовых-клиноптилолитовых и клиноптилолит-стильбитовых пород на их состав, структуру и сорбционную нефтеемкость. Энергонапряженность вибрационного истирателя составляла 12 Вт/г; доза под-веденной к веществу механической энергии-2.16 кДж/г; отношение массы стальных размольных тел к массе образца-32 : 1. Образцы изучены методами сканирующей электронной микроскопии, рентгенофазового анализа, инфракрасной спектроскопии, дифференциальной сканирующей калориметрии, термогравиметрии, низкотемпературной адсорбции азота. Найдено, что клиноптилолит-стильбитовая или клиноптилолитовая породы, модифицированные 20 мас. % ПВС, имеют улучшенную на 15-18% нефтеемкость на твердой поверхности.
Ключевые слова: цеолиты, клиноптилолит, поливиниловый спирт, механоактивация, нефтесорбенты
... This is following the lanthanum nanoparticle structures and shapes in a previous study (Maheshwaran et al., 2021). The obtained image of SEM of polyaniline (Fig. 4b) shows the amorphous nature of polyaniline grains and these are well interconnected (Olad et al., 2011). Fig. 4c illustrates the high magnification of the surface of MPANI@La nanocomposite. ...
Herein, magnetic polyaniline was modified with lanthanum nanoparticles ([email protected]) as adsorbent, aiming to the treatment of high phosphate-containing aquatic solutions. High valent lanthanum doped with polyaniline was a promising adsorbent to uptake phosphate ions with possible electrostatic interaction and cation exchange process. The functional groups, composition, surface morphology, and magnetic property of the adsorbent were investigated using Fourier Transform-Infrared Spectroscopy (FTIR), Energy Dispersive X-ray (EDX), Scanning Electron Microscopic (SEM), and Vibrating Sample Magnetometer (VSM), respectively. During the experimental process, [email protected] has removed phosphate ions from water >90%, with 80 mg adsorbent, and shaking for 150 min at room temperature. In this regard, the process was fitted with the Pseudo-second-order kinetic model (R2 > 0.999) and the Langmuir isotherm (R2 > 0.99). The proposed nanoparticles provided an appropriate adsorption capacity (qm) of 45.24 mg.g-1 at pH 4 for phosphate ions. Besides, the adsorbent can be used with an efficiency of 92.49% up to three times that reduced to 52.89% after ten times. In addition, the adsorption process was justified by thermodynamics which confirmed the proposed adsorption mechanism. Hence, the models were provided surface adsorption, monolayer pattern, and the physical mechanism of the phosphate removal process using [email protected] Hence the proposed adsorbent can be used as an alternative adsorbent in environmental water remediation.
... SEM images of CQDs/PANI nanocomposites suggest about their amorphous structure (Fig. 2A). CQDs/PANI nanocomposites consist of small rods, thin wires and web-like network of fibers [32]. CQDs are non-uniformly adsorbed on all over the surface of PANI (Fig. 2B). ...
A label-free chemo-probe comprising carbon quantum dots/polyaniline (CQDs/PANI) nanocomposites was developed for the sensitive and selective detection of mercury ions (Hg²⁺). CQDs/PANI nanocomposites were synthesized through one-step complexation reaction method. Present work represents a thorough study of structural and functional properties of CQDs/PANI nanocomposites. CQDs/PANI nanocomposites consist of fibrous network type of structure with mean particle size of 53.09 nm. Polymer nanocomposites exhibit amorphous nature with average crystallite size of 5.19 nm. CQDs/PANI nanocomposites exhibit high thermal stability up to 750 °C. Raman spectroscopy was used in sensitive and selective detection of Hg²⁺ ions in dynamic range of 0.01–0.1 ppm. Limit of detection (LOD) and limit of quantification (LOQ) for Hg²⁺ ions were obtained to be 0.017–0.031 ppm, respectively. CQDs/PANI nanocomposite-based sensing probe was found to be highly effective in pH range 3–7 for detection of Hg²⁺ ions. The proposed sensing probe was positively tested in real soil samples for detection of Hg²⁺ ions. It has shown good reproducibility and all the recorded observations indicate that CQDs/PANI nanocomposites can act as potential candidate for sensing of Hg²⁺ ions in environmental applications.
... In search of further improvement PANI along with various forms of silica crystalline such as zeolite, bentonite, silica gel, hexagonal mesoporous silica, clinoptilolite, and attapulgite were applied to prepare PANI/ silica nanocomposites for metal ions/ dye removal application. Mostly, the PANI/ silica nanocomposites are used by researchers for humic acid, toxic dyes, hazardous metal ions (copper(II), nickel(II), cadmium(II), chromium(VI), mercury(II), molybdenum(VI), and tungsten(VI)) removal from aqueous solution (Gupta et al. 2014;Javadian et al. 2013a;Javadian and Taghavi 2014;Najim and Salim 2017;Olad et al. 2012;RYABCHENKO et al. 2016;Shyaa et al. 2015;Wang et al. 2011). Other than focusing only on the removal efficiency, researchers have also observed the impact of different experimental factors on the adsorption capacity or removal efficiency, such as amount of adsorbent, pH levels, contact duration, temperature, and preliminary concentration of used toxic dyes or heavy metal ions. ...
Attaining a sustainable environment has become a prime area of research interest, as it is an utmost necessity for a healthy life. Hence, ample studies have been carried out in adopting different processes and utilizing various materials to attain the goal. Herein, we present an exclusive discussion on one such material, i.e., polyaniline (PANI) and its derivatives. Being an intrinsic conducting type, it has grabbed more attention due to its durability in different doped/un-doped states, promptness in structural alteration, and solution processability. This review presents an exhaustive discussion on published reports showing utilization of PANI and its derivative in various forms like pure and composites, for cleaning the environment through adsorption, photodegradation, etc., and the various methods adopted in order to achieve an optimum operating condition to obtain the maximum outcome. In addition to these merits and demerits, various technical challenges faced with materials have been also presented. Therefore, it is expected that this piece of work, presenting the exhaustive discussion on PANI and; its derivatives would help to develop a better understanding of this excellent conducting polymer PANI and provide a state of art on the role of this material for attaining sustainable surroundings for the living beings.
Graphical abstract
... In all patterns, the diffraction peaks of clinoptilolite have appeared because it consists of a majority of the samples. According to JCPDS No. 39-1383, these peaks agree with the standard pattern assigned in the literature (Olad et al. 2011 ...
Aniline and its derivate are critical environmental pollutants, and thus, the introduction of an eco-friendly catalyst for removing them is an important research future. The ZnO supported on the ball-mill prepared clinoptilolite nanoparticles (CNPs) was prepared via an ion-exchange process followed by the calcination process. The amount of loaded ZnO in the ZnO-CNP (CZ) samples varied as 0.54, 0.63, 0.72, and 0.86 meq/g as the Zn(II) concentration in the ion-exchange solution varied from 0.1 to 0.5 M. The ZnO-CNP catalyst was briefly characterized by XRD, FTIR, and DRS techniques. The pHpzc value for the various ZnO-CNPs was about 7.1 that had no change with the ZnO loading. By applying the Scherrer equation on the XRD results, a nano-dimension of about 50 nm was obtained for the catalyst. Bandgap energy of the ZnO-CNP samples was estimated by applying the Kubelka-Munk equation on the DRS reflectance spectra. The value for the CZ2 catalyst was about 3.64 eV. The supported ZnO-CNP sample was then used in the photodegradation of 2,4-dichloroaniline (DCA). Raw zeolite showed a relatively low photocatalytic activity. The degradation efficiency was followed by recording the absorbance of the DCA solution by UV-Vis spectrophotometer. The effects of the essential critical operating factors on the degradation efficiency were kinetically studied by applying the Hinshelwood equation to the results. The ZnO-CNP catalyst with 2 w% ZnO showed the best photocatalytic rate in the optimal conditions of 0.75 g/L, CDCA: 15 ppm, and the initial pH: 5.8. Finally, HPLC analysis of the blank and the photodegraded DCA solutions at 180 and 300 min confirmed 74 and 87% of DCA molecules were degraded during these times. The results confirm that supported ZnO onto clinoptilolite caused enhanced photocatalytic activity because the zeolite internal electrical field prevents the e−/h+ recombination.
