Presence Of Cetyltrimethylammonium Bromide Research Articles

Surfactant‐Directed Engineering of Hierarchical Porous Heteroatom‐Doped Carbons for High‐Energy Supercapacitors

Hierarchical porous heteroatom–doped carbons (HDCs) are readily fabricated through direct carbonization of polyimide precursors obtained in the presence of cetyltrimethylammonium bromide as a structure‐directing agent, showcasing tunable morphologies and porosities. The symmetric supercapacitor assembled by the optimized HDC electrodes with an aqueous electrolyte delivers a high specific capacitance (168 F g−1 at 0.5 A g−1), excellent rate capability (83.3% retention from 0.5 to 20 A g−1), and outstanding cycling stability (almost no capacitance fading after 10 000 cycles). Furthermore, the cell possesses a remarkable energy density of 8.4 Wh kg−1 at a power density of 150 W kg−1 and still maintains an energy density of 7 Wh kg−1 even at a high power density of 6000 W kg−1. Such exceptional supercapacitive performance shall be credited to the enlarged accessible surface area and pore volume for sufficient electrolyte contact and reservoir, chemically doped carbon skeleton for refined wettability, and high electronic conductivity as well as additional pseudocapacitive behavior. This work may open up a new possibility for fabricating low‐cost, lightweight, and durable supercapacitors with balanced energy and power delivery.

Fabrication of zinc/silver binary nanoparticles, their enhanced microbial and adsorbing properties

Monometallic ZnO nanoparticles were prepared by hydrolysis of zinc acetate with ammonium hydroxide solution. Bimetallic zinc-silver nanoparticles (ZnO-AgNPs) were prepared using metal displacement galvanic cell reaction in presence of cetyltrimethylammonium bromide (CTAB). The optical and photo-physical properties of both NPs were determined. Surface plasmon resonance (SPR) intensity of ZnO-AgNPs depends on the ratio of metal salt precursors and other experimental conditions. The optical band gap (2.98 eV), agglomeration number (26819.92), and molar concentration (1.14 × 10−4 mol/liter) of ZnO-AgNPs were determined. Langmuir adsorption monolayer, Freundlich, intraparticles diffusion and multilayer adsorption isotherms used for the determination of maximum adsorption efficiency and adsorption isotherm parameters to the removal of safranin dye from an aqueous solution. The kinetics of safranin removal has also been discussed with pseudo-first order, pseudo-second order, intraparticle diffusion and multilayer kinetic models. The antibacterial and antifungal activities of ZnO, Ag and ZnO-AgNPs were determined against human pathogens using growth kinetic and disk diffusion methods. The concentrations of ZnO-AgNPs have significant effect on the bacterial growth kinetics. The death rate constants increase with increasing the NPs concentrations. It has been found that the ZnO-AgNPs hold higher microbial activities than that of monometallic counterpart, ZnO and AgNPs. Mechanism of bacterial growth and death was discussed.

Effect of Surfactants on Shape of Gold Nanoparticles

In a binary mixture of cetyltrimethylammonium bromide (CTAB) and benzyldimethyltetradecyl ammonium chloride (BDTAC), gold nanorods with a maximum absorption of longitudinal plasmon resonance up to 1600 nm have been obtained. It has been shown that the shape of the growing nanoparticles is determined by the CTAB/BDTAC molar ratio. The optimal conditions have been found for the synthesis of homogeneous nanorods with an aspect ratio of 1 : 7 in a high yield, providing their rapid formation with subsequent slow and uniform growth. The use of a CTAB/BDTAC mixture allows preventing the change in particle shape due to recrystallization during their long-term storage, as is observed in the presence of CTAB.

Magnetically Separable Chiral Periodic Mesoporous Organosilica Nanoparticles

We describe, for the first time, a successful strategy for synthesizing chiral periodic mesoporous organosilica nanoparticles (PMO NPs). The chiral PMO nanoparticles were synthesized in a sol–gel process under mild conditions; their preparation was mediated by hydrolysis and condensation of chiral-bridged organo-alkoxysilane precursor compounds, (OR‘)3Si-R-Si(OR‘)3, in the presence of cetyltrimethylammonium bromide (CTAB) surfactant. The resulting nanoparticles were composed merely from a chiral- bridged organo-alkoxysilane monomer. These systems were prepared by applying different surfactants and ligands that finally afforded monodispersed chiral PMO NPs consisting of 100% bridged-organosilane precursor. In addition, the major advancement that was achieved here was, for the first time, success in preparing magnetic chiral PMO NPs. These nanoparticles were synthesized by the co-polymerization of 1,1′-((1R,2R)-1,2-diphenylethane-1,2-diyl)bis(3-(3-(triethoxysilyl) propyl) urea) chiral monomer by an oil in water (o/w) emulsion process, to afford magnetic chiral PMO NPs with magnetite NPs in their cores. The obtained materials were characterized with high-resolution scanning electron microscopy (HR-SEM), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray (EDX) spectroscopy, powder X-ray diffraction (XRD), solid-state NMR analysis, circular dichroism (CD) analysis, and nitrogen sorption analysis (N2-BET).

Morphology controlled synthesis of 2D heterostructure Ag/WO3 nanocomposites for enhanced photoelectrochemical CO2 reduction performance

Supporting nanomaterials having strong metal-support interaction is the key to an efficient catalyst. The present paper describes a morphology-controlled synthesis of silver (Ag) nanoparticles supported on nanostructured tungsten oxide (WO3) for selective photoelectrocatalytic carbon dioxide reduction reactions (CO2RR) under visible light irradiation. Highly dispersed Ag on WO3 nanorod was synthesized by a one-pot preparation method in the presence of cetyltrimethylammonium bromide (CTAB). The synthesis strategy remained intact and reproduced by varying loading of Ag, which was further confirmed by various characterization techniques like XRD, SEM, TEM, STEM elemental mapping, Raman, XPS, FT-IR, and BET analysis. The morphological growth of the WO3 nanorod (NR) and the related mechanism was studied and discussed in the paper. 1.5 wt % Ag showed optimum loading for high dispersion over WO3-NR and efficient CO2RR with high current density (0.4 mA cm−2), towards the desired selective product formation (formic acid). The efficiency of the catalyst was further correlated with cluster vacancies on the interface of Ag particle and WO3 nanorod by positron doppler broadening (DB) spectroscopy.

PH-Responsive Wormlike Micelles Formed by an Anionic Surfactant Derived from Rosin.

A novel pH-responsive wormlike micellar viscoelastic solution was constructed by a rosin-based anionic surfactant (Na-MPA-AZO-Na) in the presence of cetyltrimethylammonium bromide (CTAB). The viscoelasticity, aggregate morphology, and pH-responsiveness of the pH-responsive wormlike micelles have been investigated through the method of rheology and cryogenic-transmission electron microscopy. Its corresponding mechanism has been studied using 1H NMR and 1H-1H 2D NOESY HNMR. The zero-shear viscosity (η0) of the wormlike micellar solution rapidly decreases by 3 orders of magnitude as the pH increases from 5.21 to 9.56. The viscoelastic fluids and water-like solutions can be converted by tuning the pH between 3.62 and 12.00, and the corresponding aggregates also transform between wormlike micelles and spherical micelles. In addition, the wormlike micellar cross-sectional diameter is approximately 10 nm, which is remarkably larger than that of the common wormlike micelles. The phenomenon can be attributed to the large steric volume of the rosin rigid skeleton. When the pH is 12.00, a "pseudo" Gemini surfactant is constructed by Na-MPA-AZO-Na and CTAB through the electrostatic interactions. Wormlike micelles also can be formed with the increasing concentrations. The η0 of the wormlike micellar system shows strong dependence on concentration with an exponent of 9.6 (η0 ∝ C9.6). This work further promotes new applications of forest resources.

Influence of PVP-PEG mixed aggregates and electrolytes on the rate of alkaline hydrolysis of benzocaine in aqueous and surfactant medium

The present work describes the effects of the interactions between the two water-soluble polymers poly(vinyl pyrrolidone) (PVP) and poly(ethylene glycol) (PEG) on the rate of the alkaline hydrolysis of benzocaine. The roles of the surfactants cetyltrimethylammonium bromide (CTABr) and sodium dodecyl sulfate (SDS) in the binding of benzocaine with PVP-PEG mixed systems has also been explored through changes in the reaction rate. Our results revealed that the reaction rate decreases with the increasing [PVP] when [PEG] is fixed. Similarly, the rate of hydrolysis also decreases on increasing [PEG] while [PVP] is fixed. The combined rate constant values for the hydrolysis of benzocaine in the aqueous and mixed PVP-PEG system (kΨ) increases with increasing [CTABr] in the lower concentration range, then decreases with further increase in [CTABr], giving a peaked profile for kΨ vs. [CTABr]. The increase in [SDS] in the mixed PVP-PEG system decreases the rate of hydrolysis. Accordingly, the observed results show that the binding constant values (i.e., the degree of association) of benzocaine with PVP-PEG in the presence of CTABr and SDS are lower. Furthermore, increasing the molecular weight of PEG in the surfactant-PVP-PEG complex decreases the binding constant values of the benzocaine-polymer complex due to the formation of less compact aggregates. The effects of electrolytes (CH3COONa, NaCl, Na2SO4, and NaNO3) were also investigated, and they were found to decrease reaction rate.

Wireless Hand-Held Device Based on Polylactic Acid-Protected, Highly Stable, CTAB-Functionalized Phosphorene for CO2 Gas Sensing.

Phosphorene is a novel two-dimensional (2D) material with exceptional properties and is connecting the gaps between graphene and transition-metal chalcogenides but having environmental instability. In this study, we present effective liquid exfoliation of few-layer phosphorene (FLP) from bulk black phosphorous (BP) in the presence of cetyltrimethylammonium bromide (CTAB), a cationic surfactant that is highly stable. It successfully stabilizes FLP in deionized water, which is consistent with obtained characterization and gas-sensing studies. Our investigation shows that the dynamic sensing response of the CTAB-grafted phosphorene (P-CTAB) sensor increases by ∼1.5 times as the relative humidity (RH) varies from 33 to 75%, which is the first published result for CO2 gas detection. The sensitivity values of the P-CTAB and P-CTAB/polylactic acid (PLA) are found to be 0.0356 and 0.0329 ppm-1, respectively, toward CO2 gas. It is notable that when a polylactic acid (PLA) membrane is introduced as a barrier layer in our fabricated Arduino-based Bluetooth-enabled hand-held device, it obstructs the environmental effect with a trace-level detection capability and negligible change over time (up to 30 days). Herein, for the first time, we discover the gas-sensing characteristics of CTAB-grafted phosphorene and witness an ultrasensitive and selective response toward CO2 gas detection.

Extraction study on recovery of nickel (II) from concentrated chloride medium with N,N′-bis(salicylaldeyde)ethylenediimine in the presence of CTAB and Brij® 35 surfactants

New extraction systems have been developed for recovery of nickel(II) from concentrated saline chloride medium (1 M) via the use of the chelating extractant, N,N′ Bis(salicylaldeyde) ethylenediimine (H2SALEN), and different surfactants namely, cetyltrimethyl, ammonium, bromide (CTAB) and polyoxyethylene (23), dodecyl either (Brij® 35).The effects of the main experimental parameters such as extraction time, pH, extractant concentration and surfactant concentration on the extraction process of nickel(II) with H2SALEN alone and H2SALEN-surfactant mixture at 30 °C were studied and compared. The findings of the examination revealed a good recovery (E = 70–80%) of nickel with H2SALEN alone in various solvents (chloroform, toluene and methylisobutylketone) in the acidic pH range (4–5). The addition of both CTAB and Brij® 35 to the aqueous phase resulted in a remarkable increase in the rate of nickel extraction by reducing the extraction time from 4 hours to 20–30 minutes. The stoichiometries of the extracted species and extraction constants were ascertained by slope analysis method. The surfactant-based extraction systems have shown high extractability and a fast separation of Ni (II) into chloroform than with the reported ones. The extraction mechanisms of nickel have been suggested.

In situ synthesis of hierarchical nitrogen-doped MoS2 microsphere with an excellent visible light-driven photocatalytic nitrogen fixation ability

A photocatalyst of high-performance hierarchical nitrogen-doped MoS2 (N-MoS2) microsphere was fabricated by an in situ hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB). The as-prepared N-MoS2 microsphere was self-assembled by extremely thin interleaving petals, where CTAB acts as a nucleation site for the formation of the interleaving petals due to the strong interaction between CTA+ and [Formula: see text]. N-MoS2 showed higher N2 fixation ability (101.2 [Formula: see text] mol/g(cat)h) than the non-doped MoS2 under the visible light irradiation, and the improved photocatalytic activity could be ascribed to that the doped N narrows the band gap, and the surface reflecting and scattering effect caused by the hierarchical structure enhance the light adsorption. The trapping experiment of active species was also investigated to evaluate the role of photogenerated electrons in the photocatalytic reaction process. Meanwhile, the possible mechanism for the formation and excellent photocatalytic performance of N-MoS2 microsphere were also presented.

Synthesis and Antibacterial Screening of Some Pyrazole Derivatives Catalyzed by Cetyltrimethylammoniumbromide (CTAB).

In this article, we have developed an eco-friendly one-pot multi-component reaction methodology employed for the green synthesis of functionalized pyrazole derivatives viz cyclo-condensation of aromatic aldehydes, ethyl acetoacetate and phenyl hydrazine and/or hydrazine hydrate in the presence of cetyltrimethylammoniumbromide (CTAB) at 90°C temperature in an aqueous medium. In the present protocol, we developed a green method for the synthesis of functionalized pyrazole derivatives through one-pot, multi-component cyclo-condensation of aromatic aldehydes, phenyl hydrazine or hydrazine hydrate and ethyl acetoacetate using cetyltrimethylammoniumbromide (CTAB) as a catalyst in water as a solvent. Our methodology confers advantages such as short reaction time, atom economy, purification of the product without using column chromatographic and hazardous solvent. The reaction is being catalyzed by cetyltrimethylammoniumbromide (CTAB) and thus, products are formed under the green reaction conditions. Initially, the reaction of benzaldehyde and phenylhydrazine with ethyl acetoacetate was carried out in water at room temperature in the absence of the catalyst; no product was obtained after 24 h (Table 1 entry 1). When the reaction was carried out using L-proline as a catalyst in ethanol at 70°C, the yield of the product was 20%. This research not only provides a green and efficient method for the synthesis of sulfinic esters but also shows new applications of electrochemistry in organic synthesis. We consider that this green and efficient synthetic protocol used to prepare sulfinic esters will have good applications in the future. In conclusion, we have developed successfully a green and efficient one-pot multi-component methodology for the synthesis of substituted pyrazoles using CTAB as a catalyst in water as a solvent with excellent yields. Purifications of compounds were achieved without the use of traditional chromatographic procedures. This methodology has advantages of operational simplicity, clean reaction profiles and relatively broad scope, which make it more attractive for the diversity oriented synthesis of these heterocyclic libraries. In this methodology, we suggest a further alternative possibility for the formation of substituted pyrazoles. The compound 7h can be used as an anticancer drug in the pharma industry.

Reorganization of Interfacial Water by an Amphiphilic Cationic Surfactant Promotes CO2 Reduction.

The presence of cetyltrimethylammonium bromide (CTAB) near the surface of a Cu electrode promotes the electrochemical reduction of CO2 to fuels. CTAB increases the CO2 reduction rate by as much as 10× and decreased the HER rate by 4×, leading to ∼75% selectivity toward the reduction of CO2. Surface enhanced infrared absorption spectroscopy (SEIRAS) was used to probe the effects of CTAB adsorption on the structure of interfacial water and CO2 reduction intermediates. HER suppression was found to arise from the displacement of interfacial water molecules from CTAB adsorption within the double layer. The enhanced CO2 reduction rate can be correlated to an increased population of atop-bound CO and the emergence of a low frequency atop-CO band. These results unravel the role of additives in improving CO2-to-fuels electrocatalysis and establishing this as a powerful methodology for directing product selectivity.

Flower-like metal-organic framework microsphere as a novel enhanced ECL luminophore to construct the coreactant-free biosensor for ultrasensitive detection of breast cancer 1 gene

Nowadays, serious restriction by aggregation quenching and proton attack in aqueous media, electrochemiluminescence (ECL) signals of emitter hardly match the requirement of ultrasensitive biomedical detection in practice. In this work, a novel flower-like metal-organic framework microsphere was formed by chelating Zn ion with carboxyl-rich tris(4,4′-dicarboxylic acid-2,2′-bipyridyl) ruthenium(II) (Ru(dcbpy)32+) in the presence of cetyltrimethylammonium bromide (CTAB), defined as ZnMOF(Ru) for simplicity. For that, the obtained ZnMOF(Ru) as a high-performance ECL emitter displayed 53-fold amplification in aqueous solution without any coreactant alternative to that of Ru(dcbpy)32+, coupled with the dramatically enhanced fluorescence quantum yield and stability of the intermediates. Thus, a “sandwich”-like ECL biosensor was developed for detecting breast cancer 1 gene (BRCA1), showing the wide linear range (1.0 fM–0.1 nM) and ultralow limit of detection (LOD) down to 0.71 fM. Hence, this work provides a universal and robust pattern to develop advanced ECL luminophores and exploit their potential applications in bioanalysis.

Effects of Surfactants on the Degradation of Diclofenac by Manganese Oxide.

Amine-containing pharmaceuticals are the most often detected pharmaceuticals in wastewater and ambient aquatic environments. They can usually be degraded by manganese oxide (MnO2), which is a common natural oxidant in soils. Surfactants often coexist with pharmaceuticals in wastewater. Some amine-containing pharmaceuticals, such as diclofenac (DIC), are acidic and are thus ionic compounds in neutral conditions. These compounds, therefore, have similar properties to surfactants. Surfactants, thus, may influence the adsorption and degradation processes of DIC by MnO2. The effect of the type of surfactant on the degradation of DIC by MnO2 was investigated in this study with the addition of two common biodegradable surfactants (cetyltrimethyl-ammonium bromide (CTAB) and sodium dodecylsulfate (SDS)). The results indicated that the cationic surfactant (CTAB) significantly increased the degradation rate in neutral and alkaline conditions. On the other hand, the anionic surfactant (SDS) slightly increased the DIC removal rate in an acidic condition but significantly decreased the removal in neutral and alkaline conditions. Coexisting cationic surfactants not only influenced the kinetics but also altered the transformation mechanism of DIC by MnO2. Decarboxylation is the main transformation mechanism of DIC in the presence of CTAB, while both decarboxylation and hydroxylation are the main transformation mechanisms in the absence of CTAB.

Effects of ionic surfactants on the nucleation and growth of cyanidin 3,5-di-O-glucoside capped zerovalent iron nanoparticles

Cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) were chosen to establish the role of ionic micelles on the morphology of cyanidin 3,5-di-O-glucoside (cyanin) assisted synthesis of zerovalent iron nanoparticles. Nucleation and growth process depends upon the presence of CTAB and SDS. CTAB exhibited catalytic sub-, post- and dilution-micellar effect for the nucleation and growth process of FeNPs formation in the present investigations. Nucleation process of FeNPs formation was inhibited in presence of SDS. The different role of SDS (inhibition) and CTAB (catalysis) micelles might be due to the strong electrostatic attraction and repulsion with Fe3+ ions and cyanin. The reduction rates of Fe3+ ions by cyanin were found to be 3.9 × 10−3, 10.2 × 10−3, and 2.6 × 10−3 s−1 for aqueous, CTAB and SDS, respectively. Transmission electron microscopic images indicate that the FeNPs are roughly spherical and poly dispersed.

Polyaniline co-doped with dodecyl benzene sulfonic acid and zwitterionic-based ionic liquids prepared by inverse emulsion polymerization

Sulfonate zwitterionic ionic liquids with methyl-imidazolium (mim.ZIL) or triphenylphosphonium (PPh3.ZIL) as the cations were mixed with dodecylbenzenesulfonic acid (DBSA) and used as co-doping agent for the synthesis of polyaniline (PANI) by inverted emulsion polymerization approach in toluene medium. The ZIL-DBSA combination resulted in PANI with higher DC conductivity (σDC) values and the better response was obtained with mim.ZIL/DBSA in a molar ratio of 1.0, with σDC corresponding to around 8 S cm−1. The presence of cetyl trimethylammonium bromide (CTAB) during the synthesis caused an additional improvement of the conductivity, reaching values as high as 16.3 and 14.0 for PANI prepared in the presence of mim.ZIL and PPh3.ZIL, respectively. Electromagnetic interference shielding effectiveness (EMI SE) of PANI samples prepared with different conditions was also investigated in the X-band frequency range. An improved EMI SE, with electromagnetic attenuation of -55 dB was observed for PANI sample prepared in the presence of CTAB and mim.ZIL/DBSA in a molar ratio of 1.0.

Stability and characterization studies of Span 80 niosomes modified with CTAB in the presence of NaCl

This work reports the study of surface and aggregation properties of formulations containing mixed niosomes of the non-ionic surfactant sorbitan monooleate (Span 80) and the cationic surfactant cetyltrimethylammonium bromide (CTAB), in concentrations of 20 and 4 mol/m3, respectively, in salt-free water and in the presence of NaCl (20, 50 and 80 mol/m3). The aim of this work was the formulation of stable Span 80 and CTAB mixed niosomes with low surfactant concentration. The mixed niosomes were prepared by ultrasonication and their properties (surface tension, particle size distribution, ζ-potential, stability over time and morphology) were measured using different techniques. Data were analyzed and compared with those of the individual surfactants. Experimental results show that the addition of salt decreased the critical micelle concentration (CMC) and the surface tension of the surfactant dispersions with relation to their free-salt formulations. The presence of CTAB in the mixed niosome bilayer decreased the particle size and increased the stability of the mixed niosomes in all the formulations studied, compared with those of single Span 80. Synergism between both surfactants was obtained in the formation of niosome bilayers for formulations in pure water and with 20 and 50 mol/m3 of salt, while antagonism was observed in that of 80 mol/m3 NaCl. These results may allow the use of CTAB adsorbed on mixed niosomes in industrial applications, taking advantage of its antiseptic and antibacterial properties and solving the limitation imposed by its high Krafft temperature.

Platinum‐Imidazolyl Schiff Base Complexes Immobilized in Periodic Mesoporous Organosilica Frameworks as Catalysts for Hydrosilylation

AbstractAn imidazolyl Schiff base‐containing periodic mesoporous organosilica (PMO) was synthesized via co‐condensation reactions between a newly prepared bis (imidazolyl)imine‐bridged bis silane and tetraethyl orthosilicate in the presence of cetyltrimethyl ammonium bromide as a soft template. The resultant as‐synthesized PMO was then employed as a solid support for platinum catalysts. This complex was fully characterized via various techniques including FTIR, solid‐state13C NMR, and 29Si‐NMR spectroscopy, as well as N2 adsorption/desorption analysis, X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) methods. In addition, the catalyst was proven to efficiently mediate hydrosilylation reactions between olefins and hydrosilanes, and it can be reused for at least five cycles without significant loss of activity.

The Sorption Performance of Cetyl Trimethyl Ammonium Bromide-Capped La0.9Sr0.1FeO3 Perovskite for Organic Pollutants from Industrial Processes.

La0.9Sr0.1FeO3 perovskite, prepared by the microwave-assisted method, was capped with cetyl trimethyl ammonium bromide (CTAB) cationic surfactant, and applied as a sorbent for the removal of the anionic Congo red (CR) dye from aqueous solutions. X-ray diffraction (XRD) patterns showed that the perovskite structure was not affected by capping; however, the particle size increased. There was a hipsochromic shift in the value of λmax of the CR absorption spectrum in the presence of CTAB, which indicated the formation of an oppositely charged dye–surfactant complex. The adsorption efficiency of CTAB-capped La0.9Sr0.1FeO3 was independent of the pH of the solution—equilibrium was reached after a few minutes. The value of the maximum adsorption capacity, qm, was 151.52 mg·g−1, which was 10-times higher than that of the pure perovskite. The proposed sorbent maintained its excellent sorption ability in the presence of the sample matrix; therefore, it can be regenerated and reused with unchanged performance.

An evolved fluorimetric determination of uranium in rock/mineral sample solutions containing hydrolysable elements such as Nb, Ta, Zr and Ti sequestered by bi-fluoride

The aim of the present paper is to develop a novel method for fluorimetric determination of uranium in rock/mineral solutions containing hydrolysable elements such as Nb, Ta, Zr and Ti sequestered by bi-fluoride. These rocks/minerals are decomposed with ammonium bi-fluoride (NH4HF2) and sulfuric acid (H2SO4) mixture. Uranium in such mineral solutions is selectively extracted into ethyl acetate with 2,3-dihydroxynaphthalene at pH 10–12 in the presence of cetyltrimethylammonium bromide, prior to its pellet fluorimetric determination. Optimizations of certain parameters such as the effects of fluoride fluxes, mineral acids, masking agents and diverse ions are discussed in detail. This method is applied for the determination of uranium in synthetic mixtures and a set of in-house reference refractory minerals including certified reference material X1807 with a high degree of accuracy and precision. The results for the refractory minerals using the proposed method are in excellent agreement with results obtained by other standard methods.The novelty of the proposed method is that the decomposition mixture (NH4HF2/H2SO4) inhibits the hydrolysis of hydrolysable elements by formation of their soluble fluoro complexes, and the separation of uranium using the complexing agent 2,3-dihydroxynaphthalene is more eco-friendly compared to existing the conventional solvent extraction system using aluminum nitrate as the salting out agent.