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... elucidate the molecular structure of HDTMA-Br chains, the FTIR spectroscopy was used and the spectrum is shown on figure 1. The most intense absorption band at 2927 and 2864cm -1 in the spectrum of HDTMA-Br are associated with the anti-symmetric and symmetric C-H stretching vibrations modes of the methylene groups. ...
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... Pada puncak 696,3-798,53 cm -1 terdapat ikatan Si-O quartz [11]. Pada puncak 950, 91 cm -1 terdapat ikatan Inner Surface Al-OH deformation [12]. Pada puncak 985, 62 cm -1 terdapat ikatan Si-O plannar stretching [12]. ...
... Pada puncak 950, 91 cm -1 terdapat ikatan Inner Surface Al-OH deformation [12]. Pada puncak 985, 62 cm -1 terdapat ikatan Si-O plannar stretching [12]. Pada puncak 1047,35-1120,64 cm -1 terdapat ikatan Si-O-Si siloxane [13]. ...
... Pada puncak 1047,35-1120,64 cm -1 terdapat ikatan Si-O-Si siloxane [13]. Pada puncak 1159,22 cm -1 terdapat ikatan Si-O normal to the plane stretching [12]. Pada puncak 1454,33 cm -1 terdapat ikatan H-O-H bending [12]. ...
Molecular sieve (MS) atau dikenal dengan saringan molekul merupakan salah satu produk yang menjadi perhatian para peneliti saat ini karena memiliki kemampuan menyaring gas atau cairan dengan lebih selektif. Molecular sieve terdiri dari dua kelompok besar yaitu molecular sieve alam dan molecular sieve sintesis. Molecular sieve sintesis biasanya diolah dari batuan zeolit atau batuan kaolin karena mengandung unsur silika dan alumina yang tinggi. Piropilit mempunyai kemiripan dengan zeolit ataupun kaolin dimana kandungan alumina dan silika cukup tinggi, sehingga batuan piropilit memiliki potensi untuk dijadikan bahan dasar pembuatan molecular sieve. Pada penelitian ini batuan piropilit diambil dari daerah Sumbermanjing, Malang Selatan. Sintsis MS dilakukan dengan metode leaching NaOH. Hasil yang diperoleh dari uji XRF untuk rasio Al/Si pada MS10, MS15, dan MS20 berturut-turut adalah sebesar 2,4, 2,2, dan 2,3. Hasil XRD menunjukkan terbentuknya 3 fasa pada sintesis MS10 dan MS15 yaitu fasa sodalite dengan sistem kristal kubik, fasa quartz dengan sistem kristal hexagonal, dan fasa diaspore dengan sistem kristal orthorhombik, sedangkan pada MS20 terbentuk fasa murni yaitu fasa sodalite. Ukuran pori hasil uji BET yang dihasilkan pada MS10, MS15, dan MS20 berturut-turut adalah sebesar 30Å (mesopori), 542 Å (makropori), dan 550 Å (makropori), sedangkan untuk surface area yang dihasilkan adalah 0,350 m2/g, 2,869 m2/g, dan 1,176 m2/g. Keberadaan gugus Si-O-Si bending, Si-O-Al, Si-O, Si-O normal to the plane stretching, Inner Surface Al-OH deformation, Si-O-Si siloxine, H-O-H, -OH, C-H stretching, H-O-H bending water ditentukan menggunakan karakterisasi FTIR.
... In the absorption spectrum of dolomite [CaMg(CO 3 ) 2 ], where the structure of the flat CO 3 2− ions is intercalated with the Ca 2+ and Mg 2+ cations, the absorption band is close to 729 cm −1 , and a band centered at 728 cm −1 can be observed in the C_A band [55][56][57]. For C_SN_1 (Figure 6b) and C_SN_2 (Figure 6c), absorption bands are shown corresponding to low-Mg calcite, namely, those centered at 1796 cm −1 , 1408 cm −1 and 1409 cm −1 , 873 cm −1 and 874 cm −1 and 712 cm −1 , a band centered at 728 cm −1 corresponding to dolomite, two bands centered at 1035 cm −1 and 540 cm −1 matching the feldspars, and a band centered at 470 cm −1 corresponding to the angular deformation of the Si-O-Si bond [55][56][57][58][59][60]. It can be seen that the band centered at 728 cm −1 has a higher intensity in the spectrum of C_A compared to the spectra of C_SN_1 and C_SN_2, which is consistent with the higher proportion of dolomite in its composition. ...
... In the case of the band centered at 800 cm −1 , it can be seen that it is accompanied by another band of lower intensity at approximately 780 cm −1 . This double band is characteristic of the symmetric Si-O stretching of quartz [55][56][57][58][59][60][61][62]. ...
... The presence of quartz is associated with the doublet at 800 cm −1 and 778 cm −1 , respectively, due to the Si-O symmetric stretching mode, as well as the band at 694 cm −1 corresponding to Si-O-Al vibrations, and also the bands centered at 522-512 cm −1 and 466-459 cm −1 , which are due to Si-O-Al (octahedral) bending and Si-O-Si angular deformation vibrations, respectively. Finally, the band located at 424-414 cm −1 is due to the bending modes of O-Ca-O [55][56][57][58][59][60][61][62][63]65]. ...
The cement manufacturing industry is one of the main greenhouse gas emission producers and also consumes a large quantity of raw materials. It is essential to reduce these emissions in order to comply with the Paris Agreement and the principles of the circular economy. The objective of this research was to develop different types of cement clinker blends using industrial waste and innovative design to produce low-energy cement. Several types of waste have been studied as alternative raw materials. Their main characteristics have been analyzed via X-ray fluorescence (XRF), X-ray diffraction (XRD), Attenuated total reflectance Fourier trans-form infrared spectroscopy (ATR-FTIR), thermal analysis (TG-DTG-DSC) and scanning electron microscopy and energy dispersive X-ray spectroscopy analysis (SEM-EDS). The results obtained from the experimental work carried out in this research focused on the study of crude blends for low-energy cement created from industrial waste. The effect of the addition of different industrial waste types, as a substitution for raw materials, in the production of low-energy cement with high dicalcium silicate content has been investigated. Thus, the dosage design has been performed using modified Bogue equations and quality indexes (LSF, AM, and SM). The calculations of both the modified Bogue equations and quality indexes necessitate knowledge of the weight percentages of CaO, SiO2, Al2O3, and Fe2O3, determined via XRF. In this theoretical design of the different blends, it has been established that a dicalcium silicate ratio of 60–65 wt % and an LSF of 78–83% as the limit are values common to all of them. The calculation basis for the crude blends has been based on calcined materials. Therefore, the chemical composition was established, following this premise. Thus, it was possible to develop cement clinker blends with compositions of 50 wt % and 100 wt % using industrial wastes. This research has shown that the clinkerization process is one of the main options for the valorization of waste and its consideration for inclusion as a raw material within the circularity of the cement industry’s production process. Thus, waste is used as a raw material for the production of a more useful substance, taking into account the fundamental principles of the circular economy.
... For example, XRD is an important technique used for elemental or chemical analysis of clays (Newman 1987, Mermut andCano 2001). Several studies have been carried out using XRD to determine the mineralogical composition of clays and the presence of minerals (Preeti andSingh 2007, Aroke andEl-Nafaty 2014). ...
Since the beginning of the present century, tests have shown that some types of clay can present antibacterial activity. In addition, the clay considered for pharmaceutical and cosmetic products have been found to be non-toxic and non-irritating materials, therefore, the use of these types of clay for cosmetic and pharmaceutical purposes has increased in recent years. The above being said, different types of clay have been used over time due to their antibacterial properties, but the analytical methods for their characterization are just beginning to develop. This article is part of a study having as main objective the development of multifunctional antimicrobial textile materials to prevent fungal and bacterial proliferation, thus creating an antimicrobial shield for the human body, especially for blemish-prone skin. In this paperwork, a commercial blue clay was characterized through modern techniques. One of these techniques is X-ray Diffraction (XRD). Coupling SEM with an Energy Dispersive X-Ray detector (EDX), complete information of the morphology and elemental composition of the clay powder can be obtained. Additionally, a microbiological characterization was also performed in order to assess the anti fungal properties. Thus, the obtained results provided an overview of the main features of the selected blue clay. Further studies will be directed to the development of different types of clay-based dispersion and also for the characterization of different types of textile materials, in order to choose a "clay-textile" pair with improved antimicrobial activity.
... Over a range of 40 0-40 0 0 cm −1 , FT-IR analysis is employed to provide information on the characteristics of the functional groups on the surface of the NSC ( Fig. 3 ). The graph below shows broadband between 3407 -3610 cm −1 , corresponding to the elongation of hydroxyl -OHs mixed with the vibration and deformation of -OHs due to water molecules in the interfolar clay [33] . The distinctive carbonate bands were found at 1436 cm-1 and 2521 cm-1, a prominent absorption band characterizes the plan strstching of the Si-O bond at 1030 cm −1 [34] , and finally, the Si-O-Al bond pro- Table 2 The mass percentage of oxides present in NSC determined by X-ray fluorescence. ...
Adsorption of the most suitable dyes on locally available clay minerals is considered the most promising, efficient, and inexpensive approach. Indeed, the main objective of this study was to explain the selectivity of an adsorbing surface between the two dyes in a mixture of a solution, using a density functional theory (DFT) calculation based on the global electrophilic index ω of the evaluated cationic dyes. Thus, to study the effect of adsorption of these two dyes, Basic Yellow 28 (BY28) and Malachite Green (MG), in a mixture, and separated by a kind of natural clay from the city of Safi, composed mainly of Kaolinite, determined using structural and textual analysis DRX., FTIR., XRF., SEM., EDX., pHZPC. Subsequently, the study of the effect of different parameters, such as the dose of adsorbent, concentration, pH, and the temperature of the work, allows for optimizing working conditions. The experimental data were analyzed using the isothermal, Langmuir, Temkin, and Freundlich models. The Langmuir model obtained the best fit with a maximum monolayer adsorption capacity of 28.41 mg.g⁻¹ for basic yellow 28, and 23.75 mg.g⁻¹ for the malachite green in the mixture. The adsorption of the mix was found to be of a different nature (ΔH°BY28.mixt = -13.37 KJ.mol⁻¹, ΔH°MG.mixt = 9,82 KJ.mol⁻¹), while the positive value for MG.mixt of entropy 66.7 J.mol⁻¹.K⁻¹ indicated increased randomness at the solid/liquid interface. The adsorption kinetics data were correctly fitted with the pseudo-second-order kinetic model. Local Parr functions were used to accurately describe the most reactive adsorption sites, and the most selective dye was then assessed.
... When Table 3 is examined, the adsorption characteristic of Pb 2+ ions in combination with stretching vibrations of Si-O bonds appear in the region of 1281-841 cm -1 [43]. The bands from 1708 cm -1 to 1576 cm −1 correspond to the O-H bending vibrations of H2O molecules [44]. Stretching vibrations of Fe-O bonds appear in the region of 648-515 cm −1 . ...
In this study, the natural clay was modified and removal of Pb2+ ions synthetically prepared aqueous solutions using this modified clay was investigated. The parameters affecting the adsorption efficiency were examined in the study. In the result of studies, the suitability of the adsorption data to classic adsorption models, and adsorption kinetics were determined. In the experiments, it has been determined that pH 5 provides optimum removal conditions of adsorption and adsorption reached equilibrium in approximately 15 min. The highest removal efficiency was found to be 82.13% with the addition of 3 g L-1 adsorbent at a stirring speed of 200 rpm. As the lead concentration of the wastewater increases, the amount of lead retained per dry unit weight of the modified natural clay also increases. Experimental data showed that Pb2+ removal was consistent with Temkin adsorption model. Calculated thermodynamic constants showed that adsorption is exothermic and physical. KEY WORDS: Adsorption, Isotherm, Lead removal, Natural clay, Thermodynamic constants Bull. Chem. Soc. Ethiop. 2023, 37(1), 231-244. DOI: https://dx.doi.org/10.4314/bcse.v37i1.18
... In contrast, in the HDTMA-Br-modified zeolite spectrum, the peaks at 2852 and 2929 cm − 1 are ascribed to the symmetric and asymmetric stretching states of C-H in the HDTMA-Br aliphatic chain (Cheng et al., 2013;Ammar, 2016;Malakootian et al., 2019;Yang et al., 2019). The absorption bands at 2929 and 2852 cm − 1 in the spectrum of HDTMA-Br are associated with the antisymmetric and symmetric C-H stretching vibration modes of the methylene groups (Aroke and El-Nafaty, 2014). The bands between 1410 and 1370 cm − 1 are attributed to the scissoring modes of CH 3 -N and CH 3 -R symmetric stretching vibrations. ...
Hexadecyltrimethylammonium-bromide-activated zeolite nanoparticles coated with copper sulfide (ZEO/HDTMA-Br/CuS) was evaluated as a photocatalyst under sunlight for the degradation of metronidazole (MET). The surface and structural characteristics of ZEO/HDTMA-Br/CuS and other materials used in this study were analyzed using field emission-scanning electron microscopy, Fourier transform infrared and ultraviolet–visible diffuse reflectance spectroscopies, X-ray diffraction, Brunauer–Emmett–Teller surface area and Barrett–Joyner–Halenda pore size and volume analyses, and pH of zero charge test. ZEO/HDTMA-Br/CuS exhibited excellent surface and structural catalytic properties. For a comprehensive study of the degradation process, several parameters, such as the pH (3–11), MET concentration (10–30 mg/L), ZEO/HDTMA-Br/CuS dose (0.005–0.1 g/L), reaction time (5–200 min), and H2O2 concentration (50–200 mg/L), were optimized. ZEO/HDTMA-Br/CuS achieved 100% degradation efficiency when 10 mg/L MET was used under the optimum conditions: pH = 7, ZEO/HDTMA-Br/CuS dose = 0.01 g/L, and reaction time = 180 min. The degradation efficiency increased when the concentration of H2O2 was increased from 50 to 150 mg/L and decreased with further increase to 200 mg/L, indicating that the efficiency of MET degradation highly depends on the concentration of H2O2 in an aqueous solution. The degradation kinetics analysis revealed that the degradation is of the pseudo first-order. Thus, ZEO/HDTMA-Br/CuS proved to be an exceptional catalyst for the photodegradation of MET in aqueous media.
... The SMAC-T and SMAC-R spectra show a new absorption peak at 2974 cm -1 , indicating aliphatic sp 3 C-H stretching vibrations from HDTMA-Br and SLS. The absorption peak at 1700 cm -1 indicates the stretching vibration of (CH3)3-N + from the surfactant HDTMA-Br [13]. The absorption peak is relatively weak at 1371.25 cm -1 , indicating the presence of a S=O functional group originating from the SLS surfactant [14]. ...
The synthesis of surfactant-modified activated carbon (SMAC) has been widely studied. However, no research has been conducted to study SMAC concentrations higher than the critical micellar concentration. Therefore, in this study, SMAC was synthesized using anionic and cationic surfactants above CMC (Critical Micelle Concentration) and compared with SMAC below CMC and coconut husk-based activated carbon. This study aimed to determine the surface profile of SMAC and the characteristics and mechanism of metal ion adsorption by SMAC. The selected metal ions were Cr(VI) cations and NH4+ cations as a reference. SMAC was prepared by modifying coconut shell-based activated carbon with anionic surfactant SLS (Sodium Lauryl Sulfate) and cationic surfactant HDTMA-Br (Hexadecyl Trimethyl Ammonium Bromide). Modification of SMAC was performed by three different methods: (a) activated carbon was added gradually with SLS followed by HDTMA-Br, (b) activated carbon was added with HDTMA-Br followed by SLS, (c) activated carbon was mixed with SLS and HDTMA-Br simultaneously. All synthesized SMAC were characterized using FTIR, GSA (Gas Sorption Analyzer), and zeta potential. The FTIR analysis results showed that the synthesized SMAC comprised S=O and (CH3)3N+ groups derived from surfactants. GSA analysis revealed that SMAC has a surface area of 36.790 m2/g, and it was more stable than activated carbon according to the zeta potential result. In this study, the efficiency of SLS and HDTMA-Br in synthesizing SMAC was 99.98% and 95.85%, respectively. SMAC synthesis using method c resulted in Cr(VI) adsorption efficiency of 93.50% and NH4+ adsorption efficiency of 87.37%. In comparison, SMAC below CMC has adsorption capacities of 93.41% for Cr(VI) and 85.05% for NH4+, respectively, whereas Cr(VI) adsorption efficiency by coconut shell-based activated carbon was 99.98%.
... For Lap HDTMA, the two bands at 2,920 and 2,853 cm À1 correspond to the -C-H asymmetric and symmetric stretching vibrations, respectively. The bands at 1,470 and 1,488 cm À1 correspond to the bending vibrations of -CH 3 and to the CH 3 of N(CH 3 ) 3 asymmetric bending of the ammonium salt (Ologundudu et al. 2016;Aroke & El-Nafaty 2014). For Lap HDPy sample, the first band at 3,053 cm À1 is attributed to the pyridine vibration, the two bands 2,920 and 2,853 cm À1 are attributed to the -C-H asymmetric and symmetric stretching vibrations and the two bands at 1,470 and 1,488 cm À1 are attributed to the aromatic C ¼ C vibration and aliphatic C-H stretching (Bors et al. 2001;Ologundudu et al. 2016;Aroke & El-Nafaty 2014). ...
... The bands at 1,470 and 1,488 cm À1 correspond to the bending vibrations of -CH 3 and to the CH 3 of N(CH 3 ) 3 asymmetric bending of the ammonium salt (Ologundudu et al. 2016;Aroke & El-Nafaty 2014). For Lap HDPy sample, the first band at 3,053 cm À1 is attributed to the pyridine vibration, the two bands 2,920 and 2,853 cm À1 are attributed to the -C-H asymmetric and symmetric stretching vibrations and the two bands at 1,470 and 1,488 cm À1 are attributed to the aromatic C ¼ C vibration and aliphatic C-H stretching (Bors et al. 2001;Ologundudu et al. 2016;Aroke & El-Nafaty 2014). ...
Safe drinking water is a necessity for every human being, but clean water is scarce and not easily available due to natural geochemical factors or industrial pollutant activity. Many issues involving water quality could be greatly improved using clays as adsorbents. We highlight for the first time, the uptake of fluoride from natural water by Laponite, synthetic hectorite clay, in raw and modified state. A series of batch adsorption experiments were carried out to evaluate the adsorption potential of the different parameters. The optimized parameters were: contact time, adsorbent dose and pH. It was found that fluoride uptake from natural water was better using raw Laponite and inorganic-modified Laponite than using organic-modified Laponite clays. Adsorbents were characterized before and after fluoride adsorption by X-ray diffraction, X-ray fluorescence, FTIR, thermo gravimetric analyses and 19F solid state NMR spectroscopy. The experimental data showed that both Langmuir and Freundlich models fitted an adsorption isotherm well. Thermodynamic parameters such as Gibbs free energy (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) were calculated. These parameters indicated that fluoride adsorption onto Laponite was nonspontaneous and endothermic in temperature range between 25 and 45 °C. HIGHLIGHTS
Fluoride removal from natural water by synthetic hectorite, named Laponite.;
Raw and modified Laponite have been used.;
Fluoride uptake from natural water was better using raw and inorganic-modified Laponite than using organic-modified Laponite clays.;
Both Langmuir and Freundlich models fitted an adsorption isotherm well.;
Adsorption onto Laponite was nonspontaneous and endothermic in temperature range between 25 and 45 °C.;
... The FT-IR spectra of pristine bentonite and functionalized bentonite (BNAPTES) are presented in Figure 1. A stretching vibration of Al 2 OH occurred at 3626 cm −1 [38]. The presence of the hydroxyl group was confirmed by the prominent peak at 3420 cm −1 [39][40][41][42]. ...
... The presence of the hydroxyl group was confirmed by the prominent peak at 3420 cm −1 [39][40][41][42]. The bending vibrations of Al-Al-OH hydroxyl group occurred at 911 cm −1 [38,43]. The modified clay showed a small band at 1485 cm -1 which is attributed to CH 2 bending mode of vibration [39] and a subtle peak at ∼1319 cm −1 was ascribed to the stretching vibration of C-N bond which further contributed to the successful grafting of organosilane to the bentonite network [44]. ...
The contamination of the aquatic environment with emerging micro-pollutants is a serious global concern. The aim of this investigation was to synthesize novel functionalized material (BNAPTES) precursor to natural bentonite in a single pot facile synthetic route. The material was utilized for efficient and selective removal of tetracycline (TC) and triclosan (TCS) in aqueous wastes. The grafting of silane was confirmed with the FT-IR (Fourier Transform Infra-Red) analysis and the EDX (Energy Dispersive X-ray) analysis showed the incorporation of amino group with the bentonite. The structural changes of clay due to silane grafting were studied with the help of XRD (X-ray Diffraction) and BET (Brunner-Emmett-Teller) surface area analyses. Batch adsorption studies showed that functionalized clay significantly increased the selectivity and adsorption capacity of bentonite for TC and TCS. The Langmuir monolayer adsorption capacity was found to be 15.36 and 17.15 mg/g for TC and TCS, respectively. The rapid uptake of TC and TCS by functionalized material followed pseudo-second-rate kinetics. Further, total of 78% of TC and 73% of TCS were removed within 5 min of contact and the adsorption equilibrium was achieved within 120 min. The influence of background electrolytes and co-existing ions indicated that TC and TCS were selective towards BNAPTES. The loading capacities of the column packed with BNAPTES were found to be 56.00 and 44.42 mg/g for TC and TCS, respectively. Further, BNAPTES was found efficient even in real water treatment since the attenuation of TC and TCS was not affected significantly in the real water matrix.
... In a particular study by researchers the polypropylene was subjected to pyrolysis by thermal degradation via CVD (chemical vapour deposition) in presence of nitrogen gas at a temperature of ~450 with a residence time of 30 min. and the percent yield obtained in different states are shown below in the pie chart [13]. Researchers then carried out the same thermal pyrolysis at ~450 via CVD in presence of nitrogen gas with the kaolin catalyst. ...
