Papers by Keyword: CTAB

Abstract: The research consists of incorporating CTAB into the layers of the the bentonite structure, integrating acid-treated bentonite with cetyltrimethylammonium bromide (CTAB), and obtaining an organic material adsorbent. The physical and chemical properties of the sample modifications are identified by employing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric/thermal analysis (TGA/DTA). The bentonite used in this study was recovered from the Trebia deposit, located on the north-western flank of the Tidiennit massif in the Nador region (northeast Morocco). The composite developed in the present study is a practical adsorbent for the treatment of industrial wastewater. CTAB was successfully inserted into acid-activated bentonite, demonstrating intercalation processes through X-ray diffraction, FTIR, SEM, and TGA/DTA. The modified Bentonite structure showed increased interlayer space due to the introduction of molecules or ions. The TGA/DTA graphs confirmed the hydrophobic alteration of Bentonite, with reduced clay dehydration and a surfactant decomposing on the surface and interlayer spaces. Morphologically, CTAB formed large particles and cavities.

Abstract: Nanoparticle addition into a fluid can increase the thermal conductivity. Such fluid is commonly called a nanofluid. Due to its improved heat transfer characteristic, nanofluid is widely used as coolant in engine or electronic equipment. In the steel heat treatment industry, nanofluid can be utilized as a quench medium. By controlling the amount of nanoparticle added in the nanofluid quench medium, the cooling rate can be adjusted. To preserve the heat transfer effectivity, the stability of the nanoparticle become very important. Hence, surfactant is quite essential to improve the particle stability and avoid particle agglomeration and sedimentation. In this study, a multiwalled carbon nanotube (MWCNT) was used as the nanoparticle in the distilled water. The concentration of the MWCNT was varied at 0.1, 0.3, and 0.5 % w/v. For the surfactant, Cetyl Trimethylammonium Bromide (CTAB) was chosen to disperse the particle better. In each of the three MWCNT variations, CTAB was added from 3 – 30% w/v. The maximum thermal conductivity obtained was in the nanofluid with 0.3% MWCNT and 5% CTAB at 0.72 W/mK. For the steel hardness, the value was roughly stable at 33 – 35 HRC in the nanofluid with no CTAB and 3 – 5% CTAB addition. Excessive surfactant addition at 30% CTAB decrease the hardness significantly up to 17 HRC.

Abstract: Targeted drug delivery systems with nanomaterials as drug carriers to specific organs can increase the therapeutic effect and reduce the side effects. Magnetic mesoporous silica nanoparticles are a multifunctional platform in drug delivery and magnetic hyperthermia therapy. In this study, the synthesis was developed with iron sand from Glagah Beach as a source for the magnetic nanoparticles formation and CTAB as a surfactant template. The research method was carried out in three steps, including the synthesis of magnetic nanoparticles (Fe₃O₄), coating of magnetic nanoparticles (Fe₃O₄@SiO₂), and surfactant-templating (Fe₃O₄@SiO₂@CTAB/SiO₂).The SEM analysis results showed that the Fe₃O₄ particles have various sizes. The weight concentration of Fe in Fe₃O₄ increased from 70.25% to 78.58% compared to Fe in iron sand by EDX analysis. The XRD results showed that the crystalline size of Fe₃O₄ and Fe₃O₄@SiO₂ particles are 6.31 nm and 2.37 nm, respectively. From the results of BET analysis, it is known that the longer sonication time, the pore diameter tends to decrease. It may be due to CTAB filling in the pore during the surfactant-templating process. The highest surface area of Fe₃O₄@SiO₂@CTAB/SiO₂ particle obtained was 14.31 m²/g with a pore diameter of 3.915 nm which has a mesoporous structure.

Abstract: Pure nickel nanoparticles with some paired grain shaped has been successfully synthesized using gamma radiation technique in aqueous system at ambient temperature without using reducing agent. Cetyl trimethylammonium bromide was used to prevent oxidation during radiolysis process and help to shape the nickel nanoparticles into spheroid. Synthesized nanoparticles were characterized using X-ray diffraction, tunnelling electron microscopy and vibrating sample magnetometer. The particles formed are crystallized with fcc phase without any oxidation state. The particle size ranging from 20 – 50 nm which consists of unique morphology of paired spheroid. Vibrating sample magnetometer analysis shows that sample has ferromagnetic properties with value of magnetic remanence smaller that bulk due to its size.

Abstract: Effect of CTAB (Cetyltrimethylammonium Bromide) surfactant concentration on synthesized CTAB modified bentonite and release of NPK has been studied. Besides, the release kinetic model was also determined. Characterizations of the modified bentonite were done using FTIR (Fourier Transform Infra-Red), XRD (X-Ray Diffraction), and SEM (Scanning Electron Microscope). The amount of released NPK was analyzed using Spectrophotometer UV-Visible and AAS (Atomic Absorption Spectrometer). The release kinetics of NPK were determined using zeroth, first, second, pseudo-first, pseudo-second order, and Korsmeyer-Peppas kinetics models. The result of the study showed that CTAB modified bentonite has been successfully synthesized for NPK slow-release fertilizer. The CTAB concentration in CTAB modified bentonite affects the amount of NPK released out of bentonite and also could reduce the release of NPK. Among modified bentonite synthesized, CMB-3 (bentonite modified by CTAB 2 times CEC of bentonite) could reduce NPK release rate in water very well. The release kinetic of NPK followed the pseudo-second order kinetics model, with the release rate constant (k) of N, P, and K were 0.0027, 0.0540, and 0.0169 g mg⁻¹ day⁻¹, respectively.

Abstract: Crystalline ZnO nanoparticles were synthesized by a mechanochemical method using zinc acetate dihydrate and sodium hydroxide as starting materials, and cetyl trimethylammonium bromide (CTAB) as a protective agent. Mechanochemical activation of the solid-state reaction was achieved at low temperatures in a rapid laboratory ball mill. A three-level full factorial experimental design was used to investigate the effect of milling time and surfactant ratio on ZnO crystallite size. The product powders were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The crystallite size of ZnO samples estimated from XRD is consistent with the SEM images and found to be less than 40 nm. The crystallite size of the ZnO decreased as the surfactant ratio increased. There is an optimal milling time of 60 minutes in order to obtain ZnO nanoparticles with the smallest average grain size. The antibacterial activity of the obtained products against Escherichia coli (E. coli) was examined, and the minimum inhibitory concentration value was 5 mg/mL. ZnO synthesized by this simple method can be considered potentially as an effective bactericidal agent.

Abstract: A facile method has been developed to fabricate ZnO microstructures by a solution route at an 80°C. The microstructures with various morphologies were fabricated in water or anhydrous ethanol by using polyvinylpyrrolidone and cetyltrimethylammonium bromide as surfactants. ZnO rods with aspect ratios up to 30 have been created successfully in water through a hydrothermal process, while novel shuttle-like ZnO microstructures were fabricated in anhydrous ethanol using a similar procedure. ZnO rods revealed wurtzite-type crystal structure according to their X-ray diffraction (XRD) patterns. The morphologies of ZnO microstructures were adjusted conveniently by changing solvents and surfactants. In addition, the sizes of ZnO microstructures decreased under a long reaction time. This morphological evolution of ZnO microstructures indicated that the growth of ZnO is susceptive to reaction time due to the reaction between ZnO and aqueous ammonia. The facile strategy described here would be utilizable for the preparation of various metal oxide microstructures.

Abstract: The uniform hexagonal barium ferrite powders were synthesized by co-precipitation method using metal chloride. The effects of the amount of hexadecyltrimethyl ammonium bromide (CTAB), the water bath and calcination temperature on the phase formation, microstructure and density of barium ferrites were systematically investigated. The results showed that the formation of uniform hexagonal barium ferrite powders was significantly influenced by the amount of CTAB and the water bath could lead to the larger grain size and density. The SEM demonstrated that the BaFe₁₂O₁₉ powders had plate-like shape with crystallite sizes varing from 150 to 200 nm. When the amount of CTAB was 0.2g/100ml and the calcination temperature was 850 °C, the barium ferrite powders were uniform which indicated that the amount of surfactant and calcination temperature were very optimum.

Abstract: Ca (OH)₂ sorbent with novel pods bundle structure were successfully synthesized by precipitation method by using Cetyltrimethylammonium bromide (CTAB) as cationic surfactant. The effects of CTAB on the morphologies of Ca (OH)₂ sorbent were investigated. The results showed that the presence of CTAB could significantly differ the shape and particle size of the Ca (OH)₂ sorbent which synthesized in ethanol media at 35°C for 30 minutes. The XRD pattern indicated that the as-prepared product were well-crystallized hexagonal phase of Ca (OH)₂ sorbent. Possible mechanisms for the CTAB assisted particle growth of Ca (OH)₂ sorbent are discussed. The Ca (OH)₂ sorbent have been studied by thermal gravimetric analyzer (TGA) at a 650oC carbonation temperature. The morphological changes and particle size of the sorbent have greatly influenced the CO₂ capture performance.

Abstract: A series of semiconductor nanophotocatalyst based on transition metal (Ni and Cr) doped ZnO nanoparticles have been synthesized in the presence of cetril methyl ammonium bromide (CTAB) by co-precipitation method. Samples were characterized by X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Field Emission Scanning Electron Microscope (FESEM), and Brunauer-Emmet-Teller (BET) method. The resulting materials were explored for the decolorization of 4 different organic dyes (methyl orange, methylene blue, malachite green, and congo red) under UV light irradiation. The resulting materials exhibited relatively higher photocatalytic decolorization than bare Ni- and Cr-doped ZnO nanoparticles with similar doping concentration