N-hexadecyltrimethylammonium Bromide Research Articles

Solid-state synthesis and physico-chemical characterization of modified smectites using natural clays from Burkina Faso

Solid-state intercalation was applied to prepare organo-smectites using cationic surfactants and natural clays containing smectite at various surfactant/smectite ratios. The surfactants enter the interlayers of smectites causing a swelling of the clays. The used clays were collected in Siétougou and Diabari villages located in the eastern part of Burkina Faso. The solid-state intercalation was successful for all four surfactants applied, n-dodecyltrimethylammonium bromide, (n-C12H25(CH3)3NBr), n-tetradecyltrimethylammonium bromide, (n-C14H29(CH3)3NBr), n-hexadecyltrimethylammonium bromide (n-C16H33(CH3)3NBr) and di-n-dodecyldimethyl­ammonium bromide ((n-C12H25)2(CH3)2NBr) at different levels of the cation exchange capacity (CEC). The synthesized organo-smectites were characterized regarding relative density, structural and textural properties. XRPD data showed a systematic increase of the basal spacing of the unit cell of the smectite up to >38 Å at 2.0-CEC loading of the surfactant. This increase indicates that the surfactants penetrated into the smectite interlayers with the surfactants being arranged parallel to the layers at low concentrations and almost perpendicular at high ones. FTIR spectra of the organo-smectites showed a decrease in the intensities of the water bands at around 1630 cm-1 and 3400 cm-1, and new specific bands close to 2920 cm-1 and 2850 cm-1 were assigned to the asymmetric and symmetric stretching of CH2 groups of the surfactants, respectively.
 
 KEY WORDS: Smectite, Organo-smectite, Surfactant, Intercalation
 
 Bull. Chem. Soc. Ethiop. 2021, 35(1), 43-59.
 DOI: https://dx.doi.org/10.4314/bcse.v35i1.4

An innovative approach to recycle boron waste by mesoporous silica production and its application in methylene blue removal

The study shows an innovative method for boron waste treatment through synthesizing mesoporous silica (MCM-41) from it. At the initial stage of the process, magnesium was extracted from the waste by HCl solution and the silica source was leached by sodium hydroxide solution from the residue. Afterwards, n-hexadecyltrimethyl ammonium bromide (CTAB) was employed as the template. XRF investigated the influence of HCl/boron waste ratio, reaction time and temperature on preparing silica source. XRD results showed the compositions of boron waste and the acid leaching residue. Four typical characteristic peaks of MCM-41 were also appeared in the XRD results. The rod shape and 2D hexagonal pore structure of synthesized MCM-41 were determined by SEM and TEM. And it possessed a high BET surface area of 1035.534 m2/g and a large average pore diameter of 2.969 nm according to the N2 physisorption results. FT-IR result indicated calcination is an effective way to remove the template. These properties suggested synthesized MCM-41 has a wide range of applications. The adsorption capacity for methylene blue (MB) on BW-MCM-41 was explored by adsorption kinetics and isotherm models fitting as well as thermodynamic study. The effect of MB solution’s pH and the adsorbent dose was studied to determine the optimal adsorption conditions.

Simultaneous Determination of Five Whitening Agents by Ion-Pair Reversed-Phase High Performance Liquid Chro- matography

ABSTRACT A gradient ion-air reversed-phase high performance liquid chromatography method was developed for simultaneous determination of 5 whitening agents (ascorbic acid (AA), magnesium ascorbyl phosphate (MAP), kojic acid (KA), arbutin (ART) and hydroquinone (HQ)). The gradient elution was performed using Inertsil ODS-3V column (250 × 4.6 mm, 5 μm). The analytes were detected by ultraviolet light absorption at the wavelength of 270 nm, the flow rate was set at 1.0 mL/min, and the sample injection volume was 10 μL. The buffer solution contains 50 mM sodium phosphate monobasic dihydrate and 2 mM n-hexadecyltrimethyl ammonium bromide at pH 4.5. The precision of the proposed method, expressed as relative standard deviation (RSD) (%), was determined by the analysis of each compound. The RSD range was from 0.23 to 0.55%. The calibration curves were found to be linear in 8.12-40.6 μg/mL (KA), 12.44-62.20 μg/mL (ART), 8.28-41.40 μg/mL (HQ), 8.16-40.80 μg/mL (MAP) and 4.25- 1.80 μg/mL (AA). The correlation coefficient of linear regression analysis (R2) was within the range of 0.9968 - 0.9997. The analytical results were satisfied for these 5 whitening agents. The recoveries ranging from 96.97% to 101.22% for lotion, and from 97.17 to 100.80% for cream, were obtained at both low and high concentrations. The proposed method is suitable for routine analysis of the 5 whitening agents in commercial cosmetic products, or examined the allowable amount of whitening agents for the Department of Health.

Synthesis and characterization of nylon 6 polymer nanocomposite using organically modified Indian bentonite

In this present research work two different organic compounds are applied for the modification of Indian origin bentonite. One is with n-hexadecyltrimethylammonium bromide (CTAB), intercalated with an interlayer of bentonite via cation exchange mechanism. Whereas, another with 3-Aminopropyl trimethoxysilane (APTES) interlayer functionalization with bentonite –OH group. APTES and CTAB–intercalated bentonites samples were further cross modified with CTAB and APTES to obtain novel co-surfactant locked organo bentonite modeling (CLOM) like matrices. Original and modified bentonite samples were comparatively evaluated by advanced characterization techniques such as, powder X-ray diffraction, Fourier-transform infrared spectroscopy, thermal gravimetric analysis (TGA). Moreover, the applicability of the developed CLOM like materials were investigated in nylon 6 nanocomposite preparation by melt compounding method using a micro twin co-rotated extruder. Additionally, CLOM-nylon-6 polymer nanocomposites were characterized by wide angle X-ray diffraction, TGA, differential scanning calorimetry, atomic force microscopy and tensile strength measurement. The observed thermograph results confirmed no significant difference in the thermal properties of the developed composites. Whereas, the significant variation observed in the tensile strength results particularly for developed composite 5% of N6-OAMSB and N6 AMOSB 5 showed 111.5 and 76.6% respective enhancement in tensile strength results when compared with a bare nylon-6 polymer.

Facile exfoliation method for improving interfacial compatibility in montmorillonite-natural rubber nanocomposites: A novel charge inversion approach

Montmorillonite (Mt) is a widely researched nano-filler in rubber compounds. Although, many methods have been reported to disperse Mt at nanoscale, up-to-date obtaining highest interfacial properties between the rubber matrix and the inorganic filler remains a challenge due to the lack of suitable preparation method to make stable dispersions of Mt. This study reports a novel, scalable and simple method to reinforce natural rubber (NR) with Mt achieving the highest degree of exfoliation and subsequently, offering high surface area for interactions between the filler and the rubber matrix. Stable cationic latex of NR was prepared by a charge inversion approach where NR latex was first treated with a quaternary ammonium surface active substance, n-hexadecyltrimethylammonium bromide (CTAB). Cationic NR latex thus prepared was directly coagulated using Mt aqueous dispersion as the coagulant. This coagulation approach facilitated the in-situ formation of a Mt-NR nanocomposite containing exfoliated and intercalated clay mineral platelets. Interfacial and stress-stain behavior of the un-vulcanized nanocomposite were further studied and compared with those of a nanocomposite prepared by the conventional latex compounding method (LCM). The results of powder X-ray diffraction (PXRD) and transmission electron microscopic (TEM) imaging of Mt-NR nanocomposite prepared via this process, confirmed that Mt platelets are exfoliated with in the rubber matrix. Further studies carried out using Mooney viscosity and green strength measurements proved that the interfacial interaction between the cationic latex and Mt was significantly improved compared to those of the nanocomposites prepared via latex compounding method.

Effect of initial adsorption coverage and dynamic adsorption layer formation at bubble surface in stability of single foam films

The paper presents the experimental studies on influence of degree of initial adsorption coverage and structure of the dynamic adsorption layer over a rising bubble on stability of single foam films formed at surfaces of solutions of surface-active-substances namely n-octanol, n-hexadecyltrimethylammonium bromide (CTAB) and polyoxyethylenesorbitan monooleate (Tween80). Stability of single foam films formed by the colliding bubble under different experimental conditions were determined on the basis of systematic measurements of a single bubble lifetime in self-elaborated set-up. The experiments were supplemented by theoretical calculations of values of rupture thicknesses of the foam films, determined according to the Radove-Dimitrov-Ivanov model of drainage, which allows to consider formation of symmetrical and unsymmetrical foam films, depending on estimated structure of the dynamic adsorption layer. It was found that film lifetime depends strongly on the structure (stage of development) of motion-induced dynamic adsorption layer over the rising bubble surface. Moreover, it was shown that the bubble with completely different degree of initial adsorption coverage can form foam film of similar stability. This effect was attributed to the fact that eventual degree of the bubble adsorption coverage can reach comparable (and in some cases even equilibrium) value before film formation with identical structure of the DAL and degree of liquid/gas interface immobilization.

Preparation of high-concentration colloid solutions of metallic copper particles and their use in metal–metal bonding processes

A high-concentration colloid solution of metallic copper nanoparticles was prepared by the reduction of copper ions in aqueous solutions, and the nanoparticles were used to study metal–metal bonding. The colloid solution of metallic copper nanoparticles was prepared by mixing an aqueous solution of CuCl2 and an aqueous solution of hydrazine (reductant) in the presence of citric acid and n-hexadecyltrimethylammonium bromide (stabilizers) at a final copper concentration as high as 0.1 M. The copper-particle size was ca. submicrometer. Many tiny particles with sizes of ca. 10–20 nm were deposited on the submicron-sized particles at high hydrazine concentrations. The tiny particles were considered to be produced through the growth of particle nuclei generated at the final reaction stage by residual hydrazine derived from the high hydrazine concentration. Metallic-copper discs were successfully bonded by annealing at 400 °C and a pressure of 1.2 MPa for 5 min in hydrogen gas with the help of the metallic-copper particles. The shear strength of the bonded copper discs was then measured. The highest shear strength of 41.7 MPa was recorded for the tiny particles/immobilized particles, which could be explained by the low melting points of the tiny particles and the increase in bulk density provided by the dominant incorporation of the tiny particles into voids between the submicron-sized particles.

The competitive adsorption of methylene blue on to Na-montmorillonite from binary solution with n-alkylytrimethylammonium surfactants

The affect of competing surfactant molecules, n-decyltrimethylammonium bromide (C10TAB) and n-hexadecyltrimethylammonium bromide (C16TAB), on the adsorption equilibrium between methylene blue (MB) and Na+-montmorillonite has been studied using visible spectrophotometry. The MB competed effectively with both these surfactants and also tetramethylammonium ions, which were used as a model for the surfactant head group. At loadings up to 50% of the CEC of the clay, all of the MB was associated with the clay or clay/surfactant system. Evidence for the presence of monomer, MB+, dimer, (MB+)2, trimer, (MB+)3, and protonated monomer, MBH2+, was obtained in each case, with the trimeric form dominanting at loading >5% of the CEC. The spectra of adsorbe MB reflected the difference in chain length between C10TAB and C16TAB and indicated that a significant amount of monomeric, MB+, was solubilized in the C16TAB surfactant clusters on the clay surface. Pre-adsorbed MB was not displaced by added C16TAB surfactant.

Fabrication of silica-coated gold nanorods and investigation of their property of photothermal conversion

This study described the preparation of silica-coated Au nanorods (AuNR/SiO2) in a colloidal solution, assessed their property of photothermal conversion, and investigated their ability to kill cancer cells using photothermal conversion. Au-seed nanoparticles were produced by reducing hydrogen tetrachloroaurate (HAuCl4) with sodium borohydride (NaBH4) in aqueous n-hexadecyltrimethylammonium bromide (CTAB) solution. AuNRs were then fabricated by reducing HAuCl4 and silver nitrate (AgNO3) with l-ascorbic acid in the aqueous CTAB solution in the presence of Au-seed nanoparticles. The as-prepared AuNRs were washed by a process composed mainly of centrifugation to remove the CTAB. The washed AuNRs were coated with silica by mixing the AuNR colloidal solution, an aqueous solution of (3-aminopropyl)trimethoxysilane, and tetraethylorthosilicate/ethanol solution with a water/ethanol solution. We found that the addition of AuNR/SiO2 in water, in mice, and in a culture medium with cancer cells, followed by irradiation with a laser, cause an increase in temperature, demonstrating that AuNR/SiO2 have the ability of photothermal conversion. In addition, the cancer cells in the culture medium were found to be killed due to the increase in temperature caused by the photothermal conversion.

Gellan gum/clay hydrogels for tissue engineering application: Mechanical, thermal behavior, cell viability, and antibacterial properties

In this study, sodium montmorillonite (Na-MMT) was successfully modified by using n-hexadecyl trimethyl ammonium bromide (CTAB) via cationic exchange to obtain an organophilic-montmorillonite (CTAB-MMT). The Na-MMT, CTAB-MMT, and a commercial montmorillonite, that is, Cloisite15A were incorporated into gellan gum (GG) hydrogel and their mechanical, physical, thermal properties, biocompatibility, and antibacterial activities were investigated. The mechanical performance results show that the GG hydrogels containing Cloisite15A required smallest volume to achieve optimum compression stress, modulus, and compression strain at 5% (w/w) compared to both Na-MMT and CTAB-MMT at 10% (w/w). Swelling ratio of GG hydrogels increased upon addition of MMT, and water vapor transmission rate (WVTR) values of all hydrogels were in the range of 1106–1890 g m−2 d−1, which were comparable to WVTR values of commercial wound dressings. Thermal behavior shows that the inclusion of Cloisite15A in GG hydrogel improved the thermal stability than its counterparts. Cell studies exhibit that the GG incorporated with Na-MMT is non-cytotoxic to human skin fibroblast cells (CRL2522), and in contrast, the GG hydrogels incorporated CTAB-MMT and Cloisite15A revealed that the cells were dying and the cell growth depleted after being cultured for 72 h. Qualitative antibacterial study revealed that GG hydrogel containing CTAB-MMT only in the sample exhibits inhibition against the Gram-positive bacteria, that is, Staphylococcus aureus and Bacillus cereus, while there was no inhibition exhibited against Gram-negative bacteria ( Escherichia coli and Klebsiella pneumoniae).

Unusual transient stabilization with stabilizers and morphology of Co-nanoparticles

Abstract Upon addition of sodium borohydride to a solution of cobalt nitrate, a transient species appears within the time of mixing, which is stable for some time ca. 10 min. The molar ratios of reactants (Co2+ ions and sodium borohydride), presence of stabilizer, ageing of an aqueous NaBH4 solution, mixing order of stabilizers sodium dodecyl sulfate (SDS), n-hexadecyltrimethylammonium bromide (CTAB), and poly(vinyl) alcohol (PVA) and reactants have immense influence on the stabilization of short-lived transient. Decomposition rate constant of transient have been determined (kobs = 0.76, 4.2, 4.9 × 10−4 s−1 for SDS, PVA and no stabilizer). The complex formation constant, KC and difference in absorption coefficients, Δϵ between SDS and Co2+ ions were found to be 2.4 × 10−2 mol−1 dm3 and 2298 mol−1 dm3 cm−1, respectively. The characteristics of the Co-nanoparticles were also studied using energy-dispersive spectroscopy (EDX), scanning electron microscopy (SEM) and transmission electron microscope (TEM). EDX spectrum XRD confirmed the presence of an elemental sulphur signal along with cobalt without any peaks of other impurities.

Organically Modified Saponites: SAXS Study of Swelling and Application in Caffeine Removal.

This study aimed to assess the capacity of saponite modified with n-hexadecyltrimethylammonium bromide (CTAB) and/or 3-aminopropyltriethoxysilane (APTS) to adsorb and remove caffeine from aqueous solutions. Powder X-ray diffraction (PXRD) revealed increased basal spacing in the modified saponites. Small-angle X-ray scattering (SAXS) confirmed the PXRD results; it also showed how the different clay layers were stacked and provided information on the swelling of natural saponite and of the saponites functionalized with CTAB and/or APTS. Thermal analyses, infrared spectroscopy, scanning electron microscopy, element chemical analysis, and textural analyses confirmed functionalization of the natural saponite. The maximum adsorption capacity at equilibrium was 80.54 mg/g, indicating that the saponite modified with 3-aminopropyltriethoxysilane constitutes an efficient and suitable caffeine adsorbent.

A novel (Zr–Ce) incorporated Ca(OH)2 nanostructure as a durable adsorbent for CO2 capture

A novel high-efficiency (Zr–Ce) incorporated Ca(OH)2 nanostructure adsorbent for CO2 capture was synthesized using calcium acetate monohydrate precursor containing n-hexadecyltrimethyl ammonium bromide and sodium hydroxide via a precipitation method. The cyclic carbonation/calcination performance of the novel adsorbent was investigated using a thermogravimetry-differential thermal analysis (TG-DTA) apparatus. The novel (Zr–Ce) incorporated Ca(OH)2 adsorbent exhibited a significantly improved CO2 adsorption capacity, cyclic stability and remarkable carbonation conversion up to ~96% for 14 carbonation/calcination cycles compared with the pure Ca(OH)2 adsorbent. This result may be due to the large Brunauer–Emmett–Teller (BET) surface area (80.23m2/g), the wide range of mesopore size distribution (2–30nm) and the presence of the high temperature sintering resistance Ce2Zr3O10 compound of the novel adsorbent.

Hydrothermally controlled growth and magnetic properties of multi-morphology manganese oxide (RMnO3, R=Ca, Sr, Ba) nano- and microcrystals

This paper presents a general hydrothermal route to multi-morphology manganese oxide (RMnO3, R=Ca, Sr, Ba) nano- and microcrystals and reports the magnetic properties of their nanowires as well. Adjustment of the synthesis conditions, particularly the change of the concentrations of n-hexadecyltrimethylammonium bromide and NaOH, led to the formation of nano- and microcrystals with wire-, belt-, pyramid-, flower-, and arrow-like morphologies. Considering the shape-dependent magnetic properties of nanocrystals, nanowires were selected as representative samples for magnetic measurements. At low temperature, the nanowires exhibited interesting competing ferromagnetic–antiferromagnetic interactions, and the magnetization values increase significantly with increasing the radius of positive ions from Ca2+ to Ba2+.

Organically and Silylation of Synthesis Nano- Clay-Magadiite

This paper is an investigation of the properties of covalently bonded magadiite/polyimide nanocomposites synthesized with magadiite and polyimide（PI）. Synthesized magadiite was organically modified by n-hexadecyl trimethyl-ammonium bromide (CTAB) and then grafted by γ-aminopropyltriethoxysilane (APTS) γ-glycidoxypropyltrimethoxysilane( GPS ) or γ-methacryloxy-propyltrimethoxysilane ( MPS ). XRD confirmed the formation of the CTAB-magadiite and showed that the basal spacing increased from 1.54 to 2.46 nm. Three silylating reagents, APTS ,GPS and MPS, were reacted with the CTAB- exchanged magadiite. The subsequent formation of the organic derivatives was confirmed by XRD (X-ray diffractometer), FTIR (Fourier transform infrared spectrometer), and 29Si CP-MAS NMR (Solid-state nuclear magnetic resonance ) spectra. The copolymerization of the APTS- GPS- and MPS- modified magadiite produced new layered silicate-organic compounds and each one contained covalent bonds between the interlayer spaces. This structure is dissimilar to that produced using conventional clay polymer systems in which the ionic interactions between silicates and organic modifiers are dominant.

Films made of cellulose nanofibrils: surface modification by adsorption of a cationic surfactant and characterization by computer-assisted electron microscopy

Films made of nanofibrils were modified by adsorption of a cationic surfactant directly on the film surfaces. The nanofibrils were prepared by 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO)-mediated oxidation and mechanical fibrillation, and were relatively homogeneous in size. The average nanofibril diameter and surface porosity was quantified based on computer-assisted field-emission scanning electron microscopy (FE-SEM). The cationic surfactant used in the adsorption was n-hexadecyl trimethylammonium bromide (cetyltrimethylammonium bromide, CTAB). The adsorption of CTAB was confirmed by Fourier transform infrared (FTIR) spectroscopy and high-resolution transmission electron microscopy (HRTEM) analyses. It was shown that the adsorbed layer of CTAB increased the hydrophobicity, without affecting the tensile index significantly. This capability, combined with the antiseptic properties of CTAB, may be a major advantage for several applications.

Preparation and Characterization of Polypropylene Composites Filled with Different Structured Mesoporous Particles

Monodisperse nanosized mesoporous particles were synthesized by sol-gel reaction. This study investigated the effects of different types of nanoparticles and amount of nanoparticles on mechanical performance of polypropylene (PP) composites. Four different types of nanoparticles, namely, mesoporous MCM-41 (without template), mesoporous MCM-41 (with template), SBA-15 (without template), and SBA-15 (with template) were considered. PP composites containing (0.5-5 wt%) mesoporous fillers were prepared by compounding. The mechanical properties of the composites determined as a function of the filler loading and the different types of nanoparticles were found to vary with the different interface between different fillers and the matrix. In addition, mechanical tests suggested that SBA-15 (without template) can be regarded as better fillers for PP because of the larger pore size (5.9 nm) and thick silica walls (3.8 nm) as comparable to MCM-41 (without template) and can simultaneously provide PP with strengthening and toughening effects at a rather low filler content. Because the P 123 (EO20PO70EO20) surfactant of large PO/EO ratio in SBA-15 (with template) possessed relatively higher hydrophobicity than the n-hexadecyltrimethylammonium bromide surfactant in MCM-41 (with template), PP/SBA-15 (with template) composite showed better mechanical properties than PP/MCM-41 (with template) composite.

Dynamic adsorption layer formation and time of bubble attachment to a mica surface in solutions of cationic surfactants (C nTABr)

The paper presents the influence of the dynamic adsorption layer (DAL) formation on time of the bubble attachment to mica surface in n-dodecyltrimethylammonium bromide (DDTABr) and n-hexadecyltrimethylammonium bromide (CTABr) solutions. Phenomena occurring during collisions of the single rising bubbles with mica plates, located at different distances (“close” and “far”) from the point of the bubble detachment, were monitored using high-speed camera. It was found that when the distance from the capillary to the mica plate was L = 3 mm (location “close”) then the time of the three-phase contact formation ( t TPC), was significantly shorter than for the location “far” ( L = 100 mm). The differences between the t TPC for the locations “close” and “far” were the largest at lowest concentration. For example in 1 × 10 −6 M CTABr solution the t TPC was 162 ± 97 ms for L = 3 mm and was prolonged to 578 ± 121 ms for L = 100 mm. Similarly, in 1 × 10 −6 M DDTABr solution the t TPC was 543 ± 79 and 1840 ± 440 ms for L = 3 and 100 mm, respectively. Longer the t TPC values at the mica location “far” were attributed to the formation of the dynamic adsorption layer (DAL), with the top pole of the rising bubble almost devoid of the adsorbed cationic surfactants. The bubble attachment to mica was due to the electric charge reversal by the cationic surfactant molecules adsorbed at the bubble surface, which led to the wetting film rupture due to electrostatic attractive interactions between oppositely charged interacting interfaces. Therefore, at the location “far” the time of the TPC formation ( t TPC “far”) was longer because there was needed an additional time to restore such degree of cationic surfactant coverage at the bubble top pole, which caused the electric charge reversal from negative to positive. It was showed that the adsorption coverages needed for the electric charge reversal at the liquid gas interface can be restored during the Δ t TPC = t TPC “far” − t TPC “close” time intervals.

Biodegradable Poly(Lactic Acid)/Organic-Montmorillonite Nanocomposites: Preparation and Characterization

In this work, the biodegradable poly(lactic acid) (PLA)/organic-montmorillonite (O-MMT) nanocomposites were successfully prepared by the in situ polymerization intercalation process of D,L-lactide with organically-modified montmorillonite which was first treated by Cu cations and second treated by n-hexadecyl trimethylammonium bromide (CTAB) cations. O-MMT was characterized by FT-IR and XRD, the results showed that Cu cations and CTAB cations had been inserted to the interlayer of MMT, and the interlayer spacing of CTAB-Cu-MMT (O-MMT) increased by 1.829nm. The biodegradable PLA/O-MMT nanocomposites were characterized by XRD, SEM, FT-IR, TG, and the results showed that silicate layers were intercalated into the PLA matrix and the biodegradable PLA/O-MMT nanocomposites were of two different types: intercalated nanocomposites and exfoliated nanocomposites. This new nanocomposites frequently exhibited remarkable improvements when compared with the neat PLA matrix. Improvements could include increased heat distortion temperature, an increase in the biodegradability rate of biodegradable polymers.

Synthesis of mesoporous silica materials (MCM-41) from iron ore tailings

Highly ordered mesoporous materials were successfully synthesized by using the iron ore tailings as the silica source and n-hexadecyltrimethyl ammonium bromide as the template. The samples were detail characterized by powder X-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy and N 2 physisorption. The as-synthesized materials had high surface area of 527 m 2 g −1 and the mean pore diameter of 2.65 nm with a well-ordered two-dimensional hexagonal structure. It is feasible to prepare mesoporous MCM-41 materials using the iron ore tailings as precursor.