Nano-sized Fe3O4 Research Articles

The beneficial role of nano-sized Fe3O4 entrapped in ultra-stable Y zeolite for the complete mineralization of phenol by heterogeneous photo-Fenton under solar light

Highly efficient, separable, and stable magnetic iron-based-photocatalysts produced from ultra-stable Y (USY) zeolite were applied, for the first time, to the photo-Fenton removal of phenol under solar light. USY Zeolite with a Si/Al molar ratio of 385 was impregnated under vacuum with an aqueous solution of Fe2+ ions and thermally treated (500–750 °C) in a reducing atmosphere. Three catalysts, Fe-USY500°C-2h, Fe-USY600°C-2h and Fe-USY750°C-2h, containing different amounts of reduced iron species entrapped in the zeolitic matrix, were obtained. The catalysts were thoroughly characterized by absorption spectrometry, X-ray powder diffraction with synchrotron source, followed by Rietveld analysis, X-ray photoelectron spectroscopy, N2 adsorption/desorption at −196 °C, high-resolution transmission electron microscopy and magnetic measurements at room temperature.The catalytic activity was evaluated in a recirculating batch photoreactor irradiated by solar light with online analysis of evolved CO2. Photo-Fenton results showed that the catalyst obtained by thermal treatment at 500 °C for 2 h under a reducing atmosphere (FeUSY-500°C-2h) was able to completely mineralize phenol in 120 min of irradiation time at pH = 4 owing to the presence of a higher content of entrapped nano-sized magnetite particles. The latter promotes the generation of hydroxyl radicals in a more efficient way than the Fe-USY catalysts prepared at 600 and 750 °C because of the higher Fe3O4 content in ultra-stable Y zeolite treated at 500 °C. The FeUSY-500°C-2h catalyst was recovered from the treated water through magnetic separation and reused five times without any significant worsening of phenol mineralization performances. The characterization of the FeUSY-500°C-2h after the photo-Fenton process demonstrated that it was perfectly stable during the reaction. The optimized catalyst was also effective in the mineralization of phenol in tap water. Finally, a possible photo-Fenton mechanism for phenol mineralization was assessed based on experimental tests carried out in the presence of scavenger molecules, demonstrating that hydroxyl radicals play a major role.

Performance of a rotating packed bed with blade packings in synthesizing nano-sized Fe3O4 particles

Nano-sized Fe3O4 particles were continuously synthesized in the rotating packed bed with blade packings where the rotational speed was set at 1800 rpm, the liquid flow rate of aqueous FeCl2/FeCl3 was kept at 0.5 L/min, and the liquid flow rate of aqueous NaOH was maintained at 0.5 L/min with the chemical co-precipitation route that the synthesis temperature was fixed at 25 °C, the FeCl2 concentration was fixed at 0.15 mol/L, the FeCl3 concentration was fixed at 0.3 mol/L, and the NaOH concentration was fixed at 1.2 mol/L. The average crystallite size and mean particle size of the as-synthesized nano-sized Fe3O4 particles were 12.7 nm and 10.9 nm, respectively. The rate of continuous synthesis of nano-sized Fe3O4 particles was 23.6 kg/day. The as-synthesized nano-sized Fe3O4 particles exhibited a superparamagnetic characteristic at 25 °C. Furthermore, the saturation magnetization of the as-synthesized nano-sized Fe3O4 particles was 66.4 emu/g. The as-synthesized nano-sized Fe3O4 particles had the Type-IV isotherm for N2 adsorption-desorption with a BET specific surface area of 109.4 m2/g. The maximum Orange G adsorption capacity of the as-synthesized nano-sized Fe3O4 particles at 25 °C and pH 3 was 55.0 mg/g. This maximum Orange G adsorption capacity was much higher than that (5.7 mg/g) of the commercial nano-sized Fe3O4 particles that were purchased from Sigma-Aldrich (SA-Fe3O4) because the as-synthesized nano-sized Fe3O4 particles had a smaller mean particle size than SA-Fe3O4. Accordingly, the as-synthesized nano-sized Fe3O4 particles are a promising magnetic adsorbent in the removal of Orange G from water.

Design and Construction of Carbon-Coated Fe3 O4 /Cr2 O3 Heterostructures Nanoparticles as High-Performance Anodes for Lithium Storage.

Transition metal oxides, highly motivated anodes for lithium-ion batteries due to high theoretical capacity, typically afflict by inferior conductivity and significant volume variation. Architecting heterogeneous structures with distinctive interfacial features can effectively regulate the electronic structure to favor electrochemical properties. Herein, an engineered carbon-coated nanosized Fe3 O4 /Cr2 O3 heterostructure with multiple interfaces is synthesized by a facile sol-gel method and subsequent heat treatment. Such ingenious components and structural design deliver rapid Li+ migration and facilitate charge transfer at the heterogeneous interface. Simultaneously, the strong coupling synergistic interactions between Fe3 O4 , Cr2 O3 , and carbon layers establish multiple interface structures and built-in electric fields, which accelerate ion/electron transport and effectively eliminate volume expansion. As a result, the multi-interface heterostructure, as a lithium-ion battery anode, exhibits superior cycling stability maintaining a reversible capacity of 651.2 mAh g-1 for 600 cycles at 2 C. The density functionaltheorycalculations not only unravel the electronic structure of the modulation but also illustrate favorable lithium-ion adsorption kinetics. This multi-interface heterostructure strategy offers a pathway for the development of advanced alkali metal-ion batteries.

Occurrences of typical PPCPs during wastewater treatment and the composting of sewage sludge with micron-sized and nano-sized Fe3O4

New pollutants, pharmaceuticals and personal care products (PPCPs), accumulate in sewage sludge (SS) in wastewater treatment plants (WWTPs), posing risks to the environment and to human health. In the present study, the fates of typical PPCPs, carbamazepine (CBZ), triclosan (TCS), ibuprofen (IBU) and galaxolide (HHCB), were examined during WW treatment. Additionally, SS collected from a WWTP was used for aerobic composting to investigate the influences of micron-sized Fe3O4 (M-Fe) and nano-sized Fe3O4 (N–Fe) on the degradation of these PPCPs and the succession of microbial communities during the composting process. The results showed that the mean concentrations of CBZ, TCS, IBU and HHCB in the influent of the WWTP were 926.5, 174.4, 8869, and 967.3 ng/g, respectively, and in the effluent were 107.6, 47.0, 283.4, and 88.4 ng/g, respectively. The removal rate averaged ∼80%, while the enrichment rates of the PPCPs in SS ranged from 37.2% to 60.5%. M-Fe and N–Fe reduced NH3 emissions by 32.9% and 54.1% and N2O emissions by 26.2% and 50.8%, respectively. Moreover, the addition of M-Fe and N–Fe effectively increased PPCP degradation rates 1.12–1.66-fold. During the whole process, the additions of M-Fe and N–Fe significantly shifted microbial community structure, and the abundances of Proteobacteria, Chloroflexi, and Actinobacteria were increased during the thermophilic stage, marking them as key PPCP-degrading phyla. Taken together, our results indicated that the addition of M-Fe and N–Fe is an effective method for improving the quality of end compost and accelerating the degradation of PPCPs.

Facile preparation of Fe3O4/ZnFe2O4/ZnS/C composite from the leaching liquor of jarosite residue as a high-performance anode material for Li-ion batteries

A Fe3O4/ZnFe2O4/ZnS/C composite is synthesized through a facile thermal decomposition method under an oxygen insufficient condition with the leaching liquor of ammonium jarosite residue and sucrose as raw materials. It reveals that the sucrose dosage (with nFe:nsucrose of 1:0, 1:1, 1:2, and 1:3, respectively) has a crucial impact on the microstructure, composition, and lithium storage property of the prepared samples. Particularly, the sample prepared with the nFe:nsucrose of 1:2 (labeled as FZ-2) has a porous structure in which nanosized Fe3O4, ZnFe2O4, and ZnS are embedded in the carbon matrix. Due to the porous morphology and synergistic effects of different components in the sample, this Fe3O4/ZnFe2O4/ZnS/C composite exhibits high lithium storage activity, superior cycling stability (928 mAh g−1 after 300 cycles at 500 mA g−1), and excellent high-rate capability (371 mAh g−1 at 5000 mA g−1). Lithium storage kinetics analysis demonstrates that the Fe3O4/ZnFe2O4/ZnS/C has much lower electrochemical reaction resistance, smaller polarization, faster Li+ diffusivity, and more remarkable pseudocapacitive behavior than the Fe2O3/ZnFe2O4 counterpart. This work realizes the low-cost and facile fabrication of high-valued anode material for LIBs and the comprehensive utilization of Fe, Zn, and S resource in jarosite residue, achieving the interdisciplinary between resource recovery and electrochemical energy storage.

Ordered sandwich silicon quantum dot/Fe3O4/reduced graphene oxide architectures for high-performance lithium-ion batteries

Iron-based oxides are one of the most promising anode materials for lithium-ion batteries (LIBs) because of their high theoretical capacity, low cost, and eco-friendliness. However, its poor cycle stability and low-rate performance limit its wide application. In this work, a novel ordered sandwich-structured nanocomposite consisting of Fe3O4, silicon quantum dots (Si-QDs), and reduced graphene oxide (rGO) is synthesized via a self-assembly approach combined with subsequent annealing. Si-QDs are vital to guide the uniform formation and homogeneous distribution of nano-sized Fe3O4 on the rGO nanosheets. The resultant Si-QDs/Fe3O4/rGO composite possesses a unique ordered sandwich structure, in which Si-QDs and Fe3O4 particles are evenly anchored on rGO nanosheets. Si-QDs/Fe3O4/rGO delivers high specific capacity, outstanding cycling stability, and rate capability. At a current density of 100 mA·g−1, it displays an initial discharge-specific capacity of 1489.6 mAh·g−1 and maintained a specific capacity of 1367.1 mAh·g−1 after 80 cycles. The crucial effect of Si-QDs on the composite's morphology, structure, and electrochemical performances is deeply investigated by corresponding characterizations. The preparation strategy may be introduced in other metal-oxide-based nanocomposites with ordered sandwich structures and points out an ingenious way to design anode materials for high-performance LIBs.

Investigation into the magnetic immobilization of lipase and its application in the synthesis of structured triacylglycerols

In this paper, sn-1,3-specific lipase from Rhizomucor miehei (RML) was immobilized with dialdehyde starch (DAS) as a support activating agent and nano-sized Fe3O4 as a magnetic carrier. The structured triacylglycerol as human milk fat substitutes enriched with OPO was produced. The results showed that the fixed load of lipase was 52.41 mg/g. The enzyme activity recovery was 57.82%. Compared with free lipase, the relative enzyme activity of RML immobilized in magnetic particle was kept at 92% when placing 10 h in a methanol solution. The lipase immobilized in magnetic particle had an average particle diameter of 169 nm and was applied in the synthesis reaction of 1,3-dioleoyl-2-palmitoylglycerol (OPO) by using tripalmitin (PPP) and oleic acid (OA) as raw materials. Under the optimal reaction conditions of 10% immobilized lipase, 5:1 substrate molar ratio (OA/PPP), 50 °C reaction temperature and 7 h reaction time, the product's OPO content was 43.97%, and the content of triacylglycerols rich in palmitic acid at the sn-2 position was 83.32%. After eight repeated uses at 50 °C, the relative activity of RML immobilized in magnetic particle remained above 71%. The synthesized OPO has potential to be used in infant formulas.

Trace detection of methcathinone in sewage using targeted extraction based on magnetic molecularly imprinted polymers coupled with liquid chromatography-tandem mass spectrometry.

Methcathinone, a new psychoactive substance (NPS), poses a serious threat to public health. Therefore, there is an urgent need to develop a reliable, selective, sensitive and simple analytical technique for monitoring trace amounts of this target NPS in complex matrices. For this purpose, magnetic molecularly imprinted polymers (MMIPs) based on MIPs combined with nano-sized magnetic Fe3O4 were developed for the specific enrichment of methcathinone in wastewater. The binding properties and selectivity of MMIPs toward methcathinone were evaluated and compared with non-imprinted polymer (MNIPs). For sensitive and selective extraction and determination of the target methcathinone, magnetic solid-phase extraction (MSPE) based on MMIPs was combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Under optimized conditions, the proposed method was successfully used for the detection of methcathinone in wastewater, which provided a low limit of detection of 0.3 ng L-1 and a limit of quantification of 1.0 ng L-1 with relative standard deviations of less than 6.89% for intra- and inter-day analyses. Good linearity in the range of 1-2000 ng L-1 with a coefficient of determination (R2) greater than 0.98 was observed. Moreover, a certified reference material of water sample was successfully analyzed with satisfactory results and the recoveries of spike experiments ranged from 96.35-116.7%.

Integration strategy for facile fabrication of porous carbon coated Fe3O4 nanospindles with enhanced lithium storage

Despite high capacities, the practical use of the Fe3O4-based anodes is still impeded because of poor cyclic performance caused by their large volumetric variation and pulverization during cycle. Aimed at the aforementioned problems, a composite of conformal porous carbon coated Fe3O4 nanospindles (Fe3O4 @PC) has been prepared by a well-designed integration strategy which not only simplifies the experimental steps but also restrains the severe aggregation of nano-sized Fe3O4 during carbon coating process. In particular, the superficially conformal porous carbon is demonstrated to not only accommodate the volumetric variation of the Fe3O4 nanospindles better with its flexible spongy structure but also provide fast and stable diffusion pathways for ions through its defect-enriched pores. With a combination of superficially conformal porous carbon coating, nano-sized one-dimensional structure and Fe–O–C chemical bonding, therefore, the as-prepared Fe3O4 @PC shows outstanding electrochemical behaviors in terms of high capacity, long lifespan and good rate performance, demonstrating 896.3 and 592.9 mA h g−1 after 400 cycles at 200 and 1000 mA g−1, respectively. Moreover, this work is expected to open up new avenues for designing and preparing other conformal porous carbon coated metal oxides for advanced LIB anodes or other applications.

Iron dust explosion characteristics with small amount of nano-sized Fe2O3 and Fe3O4 particles

Iron powder, as one of the most abundant metal fuels that can be used as recyclable carriers of clean energy, is a promising alternative to fossil fuels in a future low-carbon economy. It may pose a potential explosion hazard during the process of processing, storage, transport, and reduction/oxidation (redox). The explosion characteristics of iron dust in air were undertaken via a 20 L spherical explosion chamber with an emphasis on minimum explosion concentration (MEC) of iron dust. The alternative method of combustion duration time (tc) was used to determine MEC and compared with the standardized over pressure method. Two kinds of nano-sized iron oxides (Fe2O3 and Fe3O4) were used as inertants to determine the inhibition effect of different oxidation products. The iron dust explosion products with various shapes and sizes were found to be able to grow up 4–6 times of the iron dust for the first time. Adding small amount of Fe2O3 or Fe3O4 could reduce the explosion severity and sensitivity of iron dust. The MEC data determined by both methods were comparable. The addition of 5 % oxide has obvious inhibition effect under 1500 g/m3 concentration. With the increase of oxide concentration to 10 %, the inerting effect increases, and the MEC of iron dust increases more than 3 times. The increase of dust concentration will weaken the inerting effect. When the concentration increases from 500 g/m3 to 3000 g/m3, the weakening effect of 10 % Fe2O3 on the explosion pressure decreases from 38.45 % to 2.24 %, and 10 % Fe3O4 decreases from 46.21 % to 10.63 %. Unlike coal, biomass or aluminum dusts, the iron dust explosion was found to have a unique secondary acceleration of pressure rise rate for the first time. These results provide a fundamental basis to mitigate the iron dust explosion via solid inerting method without adding extra elements.

Characterization of magnetic properties of ferric oxide from Sekotong beach iron sand West Lombok Indonesia

In the present study preparation and characterization of ferric oxide (Fe3O4) with ball milling has been done, for enhancing magnetic properties. Fe3O4 is obtained from the iron sands Sekotong Beach, West Lombok, Indonesia. The Fe3O4 has gained its importance due to its low cost, substitute for pure BaFe. Nano-sized Fe3O4 has applications in industrial fields such as ceramics, catalysts, energy storage, magnetic data storage, ferrofluids, as well as in medical diagnosis. Characterization of iron sand samples using Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX), and Permagraph Magnet Physik Germany, at BRIN LIPI Bandung. The result of characterization using SEM-EDX shows that iron sand samples contain Fe and O elements derived from Phase Magnetite (Fe3O4). The magnetic properties: Magnetic remanence (Mr), coersivity (Hc), maximum energy product (BH)) of magnetic, 3,01 kG, 4,97 kOe, 3,72 MGOe respectively. A small coercivity value is one of the characteristics of super paramagnetic materials.

Adsorption of Cationic Dyes on a Magnetic 3D Spongin Scaffold with Nano-Sized Fe3O4 Cores.

The renewable, proteinaceous, marine biopolymer spongin is yet the focus of modern research. The preparation of a magnetic three-dimensional (3D) spongin scaffold with nano-sized Fe3O4 cores is reported here for the first time. The formation of this magnetic spongin–Fe3O4 composite was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA) (TGA-DTA), vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FTIR), and zeta potential analyses. Field emission scanning electron microscopy (FE-SEM) confirmed the formation of well-dispersed spherical nanoparticles tightly bound to the spongin scaffold. The magnetic spongin–Fe3O4 composite showed significant removal efficiency for two cationic dyes (i.e., crystal violet (CV) and methylene blue (MB)). Adsorption experiments revealed that the prepared material is a fast, high-capacity (77 mg/g), yet selective adsorbent for MB. This behavior was attributed to the creation of strong electrostatic interactions between the spongin–Fe3O4 and MB or CV, which was reflected by adsorption mechanism evaluations. The adsorption of MB and CV was found to be a function of pH, with maximum removal performance being observed over a wide pH range (pH = 5.5–11). In this work, we combined Fe3O4 nanoparticles and spongin scaffold properties into one unique composite, named magnetic spongin scaffold, in our attempt to create a sustainable absorbent for organic wastewater treatment. The appropriative mechanism of adsorption of the cationic dyes on a magnetic 3D spongin scaffold is proposed. Removal of organic dyes and other contaminants is essential to ensure healthy water and prevent various diseases. On the other hand, in many cases, dyes are used as models to demonstrate the adsorption properties of nanostructures. Due to the good absorption properties of magnetic spongin, it can be proposed as a green and uncomplicated adsorbent for the removal of different organic contaminants and, furthermore, as a carrier in drug delivery applications.

An Influence of Nano-Sized Fillers Fe3O4, ZnO on the Thermal Oxidation Resistance of Inhibited Polyethylene

An Influence of Nano-Sized Fillers Fe3O4, ZnO on the Thermal Oxidation Resistance of Inhibited Polyethylene

Preparation of Iron Nitride Material from Natural Iron Sand

Iron nitride is a promising material for soft magnetic composite. In the current research, iron nitride compound was produced from natural iron sand, involving coprecipitation and gas nitriding. Prior to coprecipitation, natural iron sands were separated magnetically to obtain pure Fe3O4. Afterward, the coprecipitation was carried out to obtain nanosized Fe3O4. Gas nitriding of Fe3O4 powders was performed at different temperatures i.e. 500 °C, 600 °C and 700 °C, under flowing NH3 gas. Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) are used to investigate the phases obtained after the nitriding process. XRD patterns of the resulted powder indicate that nitriding temperature at 600 °C and 700 °C can produce iron nitride material, i.e. ε-Fe3N. While nitriding temperature of 500 °C is not able to yield iron nitrides. SEM examination reveals that the ε-Fe3N has irregular lamellar morphology. Some impurities are still detected, in the form of Fe3O4, Fe2O3, Ti2O3 and TiO2. Further works regarding the examination of the magnetic properties of the powders will be carried out.

The Phosphate-Based Composite Materials Filled with Nano-Sized BaTiO3 and Fe3O4: Toward the Unfired Multiferroic Materials.

The composite material filled with nano-sized BaTiO and FeO was designed and studied. The aluminium phosphate ceramics was used as a matrix. The XRD analysis demonstrates only the crystalline structure of the fillers used. The thermogravimetric analysis proves the thermal stability of the composites up to 950 K. The Maxwell–Wagner relaxation was observed in the dielectric spectra of the investigated composites. The dielectric spectroscopy proves the close contact between the nanoparticles with the different ferroic ordering. The phosphate-based composites have been proved to be a prospective candidate for the multiphase multiferroic materials design and development.

Decoration of SiO2 and Fe3O4 Nanoparticles onto the Surface of MWCNT-Grafted Glass Fibers: A Simple Approach for the Creation of Binary Nanoparticle Hierarchical and Multifunctional Composite Interphases.

We report on a versatile method for chemically grafting multiwalled carbon nanotubes (MWCNTs) onto the surface of conventional glass fibers (GFs), as well as depositing further silica (SiO2) or superparamagnetic (SPM) magnetite (Fe3O4) nanoparticles (NPs) creating novel hierarchical reinforcements. The CNT-grafted GFs (GF-CNT) were utilized further as the support to decorate nano-sized SiO2 or Fe3O4 via electrostatic interactions, resulting finally into double hierarchy reinforcements. SiO2 NPs were first used as model nano-particulate objects to investigate the interfacial adhesion properties of binary coated GFs (denoted as GF-CNT/SiO2) in epoxy matrix via single fiber pull-out (SFPO) tests. The results indicated that the apparent interfacial shear strength (IFSS or τapp) was significantly increased compared to the GF-CNT. Fe3O4 NPs were assembled also onto CNT-grafted GFs resulting into GF-CNT/Fe3O4. The fibers exhibited a magnetic response upon being exposed to an external magnet. Scanning electron microscopy (SEM) revealed the surface morphologies of the different hierarchical fibers fabricated in this work. The interphase microstructure of GF-CNT and GF-CNT/SiO2 embedded in epoxy was investigated by transmission electron microscopy (TEM). The hybrid and hierarchical GFs are promising multifunctional reinforcements with appr. 85% increase of the IFSS as compared to typical amino-silane modified GFs. It could be envisaged that, among other purposes, GF-CNT/Fe3O4 could be potentially recyclable reinforcements, especially when embedded in thermoplastic polymer matrices.

Transformation mechanism between the frictional interface under dioctyl sebacate lubrication

In this study, an improved tribology test rig has been applied to conduct the study on transformation mechanism between the frictional interface under the lubrication of DOS with steel/steel contacts. The results indicated that the nature of wear debris was nano-sized Fe3O4 particles coated by a great deal of carbonaceous matter, which could act as a solid lubricant on the friction interface. The wear debris filled the grooves in steel surfaces and a bright black tribofilm was generated during test. The analysis results of GC-MS showed that C–C chemical bonds of DOS molecules at the tertiary carbon were easier to break during the tribochemical reaction process, and the possible tribochemical reaction mechanism of DOS molecules in this experiment was proposed.

4,4′-Isopropylidenebis(2,6-dibromophenol) Photocatalytic Debromination on Nano- and Micro-Particles Fe3O4 Surface

Background: Tetrabromobisphenol A (4,4’-isopropylidenebis(2,6-dibromophenol), TBBPA) is one of the most widely used brominated flame retardants. Due to its widespread use, high lipophilicity, and persistence, it has been detected in various environmental samples. Therefore, it is of great significance to develop methods to efficiently remove TBBPA from the contaminated environment. Objective: The aim of our study was to examine photocatalytic dehalogenation of TBBPA on microand nano-sized Fe3O4 exposed to the visible light. The Fe3O4 catalyst was chosen due to its indisputable low impact on the environment. Methods: A solution of TBBPA (1.84 × 10-4 mol dm-3) with a pH = 8 with suspended catalyst was illuminated (light intensity about 1.1x1017 photons per second, spectrum range 200-600 nm) for 1 hour. Analysis of the reaction progress was carried out by HPLC measurements of TBBPA decay and potentiometric measurements of an increase in bromide concentration. Results: The degradation process seems to be the most effective for TBBPA in the reaction mixture containing the n-Fe3O4 (t0.5 ≈ 2 min). Slightly lower degradation efficacy is observed for TBBPA degradation in the presence of the μ-Fe3O4 (decay within the first 5 min). TBBPA decomposition of both n-Fe3O4 and μ-Fe3O4 is accompanied by different bromide concentrations time-profile. Conclusion: The photogenerated electron-induced degradation by dissociative-attachment to the aromatic ring was followed by bromine ion expulsion. The micro-magnetite showed a strong tendency for adsorption of bromide anions during the process, which could be adventurous for the overall waste-decontamination process.

Analyses of magnetic properties and crystal size on Fe3O4 nanoparticle from local iron sand using PEG as soft template

Nano-sized Fe3O4 has been considered prominent in material science research due to its potential applications in multi-layered aspects. One of the simple and inexpensive methods of nanosized Fe3O4 synthesis is co-precipitation. However, this method has not provided a uniform size. Therefore, this study carried out a few modifications by using PEG-200 and PEG-1000 as a soft template with a volume ratio of 1:1, 1:3, and 1:5. The Fe precursors used in this study are iron sand from the Brantas River, Kediri-East Java, Indonesia. The XRD results showed that the use of PEG in the synthesis of Fe3O4 did not affect the Fe3O4 phase, and this study obtained a crystal size with a range of 6-12 nm. Based on morphological observations using SEM, the use of soft templates in Fe3O4 synthesis can reduce agglomeration rather than without using a PEG template. All Fe3O4 powder samples showed ferrimagnetic behavior with a saturation magnetization of 39.5-70 emu/g.

Applicability of Fe3O4 nanoparticles for improving rheological and filtration properties of bentonite-water drilling fluids in the presence of sodium, calcium, and magnesium chlorides

There are impressive efforts in conjunction with improving rheological and filtration properties of Water-Based Drilling Fluids (WBDFs) employing Nano-Particles (NPs). However, NPs’ performance in the presence of different salts has not been well assessed. This study intends to investigate the effect of Fe3O4 NPs on rheological and filtration properties of bentonite-water drilling fluids exposed to NaCl, CaCl2, and MgCl2 salts. To reach the goal specified for this study, three 0.5, 1 and 2 wt% NP concentrations, separately, were added into a salt-free and three salt-contaminated bentonite-water drilling fluids (four base fluids). So, 16 different drilling fluids were prepared for this research. The rheological models obtained by six shear rates, apparent viscosity, plastic viscosity, yield point, gel strength, and cutting carrying ability of all the drilling fluids are described in the paper. Moreover, API fluid losses (under 100 psi differential pressure), the cakes’ thickness, and the cakes’ permeability compared to the same as the salt-free base fluid, are interpreted to evaluate the NPs’ performance on filtration control ability of all the drilling fluids. The results showed that the salts weaken the rheological and filtration properties of the salt-free base fluid, while Fe3O4 NPs sustain and improve the rheological properties of salt-free and salty drilling fluids, significantly. Nano-sized Fe3O4 weakens the filtration properties of the salt-free WBDF, but it is a suitable filtration control agent for salt-contaminated drilling fluids. In a sentence, nano-Fe3O4 is a suitable additive to enhance salty-WBDFs’ performance.