Particle Specific Surface Area Research Articles

The effect of carbon addition on the synthesis process and the physical/electrocatalytic properties of FeTiO3 nanopowder produced by solution combustion synthesis method

The FeTiO3 nanopowder is a vital engineering material known for its exceptional performance in energy generation, storage, electrochemical sensors, and catalysis. However, synthesizing FeTiO3 nanopowder with high crystallinity and phase purity typically requires specialized equipment and controlled heat treatment due to the instability of Fe2+ ions. Using the one-step solution combustion synthesis (SCS) method, FeTiO3 nanopowder withe high crystallinity were successfully produced utilizing basic equipment. Additionally, the influence of carbon additives on phase transitions, as well as the physical and physicochemical properties of the synthesized powder, was examined. XRD results indicate that increasing the amount of fuel, particularly glycine, creates a stable environment for the crystallization of FeTiO3 nanoparticles. Moreover, enhancing the carbon content in precursor solutions with urea enhances reduction conditions and boosts the stability of FeTiO3 in the final product. The presence of carbon additives in glycine-fuel samples leads to unfavorable outcomes by increasing the levels of TiO2 and Fe3O4 undesirable phases. Incorporating additive carbon into the urea-synthesized precursor solution resulted in a particle size increase exceeding 50 nm and raised the combustion temperature by a minimum of 230 °C. Furthermore, the presence of 15 wt% additive carbon in the sample synthesized with glycine improved the specific surface area of particles from 2.44 m2/g to 18.41 m2/g. Obtained results have shown that achieving high crystallinity of FeTiO3 nanopowder is feasible through a one-step solution combustion synthesis process. This can be accomplished by carefully choosing the synthesis conditions, such as the type and quantity of fuel, along with the carbon additive.

Carbonyl Iron Particles' Enhanced Coating Effect Improves Magnetorheological Fluid's Dispersion Stability.

The coating effect of 1,2-bis(triethoxysilyl)ethane (BTES) on carbonyl iron particles (CIPs) was enhanced by etching with hydrochloric acid (HCl) of various concentrations, and magnetorheological fluids (MRFs) with significantly improved dispersion stability were obtained. The microstructures, coating effect, and magnetism of CIPs were examined using scanning electron microscopy (SEM), automatic surface and porosity analysis (BTE), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and a vibrating sample magnetometer (VSM), respectively. Furthermore, the rheological properties and dispersion stability of the MRFs were assessed by a rotating rheometer and a Turbiscan Tower. The results show that as the HCl concentration increased, nanopores appeared on CIPs and then disappeared, and the specific surface area of the particles increased and then decreased. When the concentration of HCl was 0.50 mol/L, the number of nanopores and the specific surface area of particles changed sharply. Not only that, the coated mass of BTES increased greatly and the saturation magnetization of particles decreased sharply. As the coated mass increased, without a magnetic field, the viscosity and shear stress of the MRFs increased, especially when the coated mass was more than 2.45 wt.%; while under a magnetic field, the viscosity and shear stress decreased, and the sedimentation rate of the MRFs decreased from 0.13 to 0.01 mm/h. By controlling the concentration of HCl for etching, the coating effect of CIPs was greatly enhanced, and thus an MRF with superior shear stress and excellent dispersion stability was obtained, which is significant in basic research and MRF-related applications.

Synthesis and characterization of mesoporous silicate as core and low generation polyamidoamine dendrimer as shell for delivery of 5-fluorouracil from their nano complex

Modern nanomedicine delivers drugs to malfunctioning cells. Several synthetic processes can change the shape, particle size, polydispersity index, surface area, and porosity of mesoporous silica nanoparticles (MSNs). Polyamidoamine (PAMAM) dendrimers are attractive polymers with circular forms, uniform distribution, well-structured branching, internal cavities, and surface terminal groups. The objective of this study is to deliver 5-fluorouracil (5-FU) as passive targeting to carcinogen cells via MSN-PAMAM-G3 nanoparticles. This study involved the direct and adaptable synthesis of MSN as the core vehicle, together with third-generation PAMAM dendrimers as the vehicle shell, with the goal of delivering the 5-FU in a targeted and controllable manner. Tetraethyl orthosilicate (TEOS) and cetyltrimethylammonium bromide (CTAB) are used as templates to make the center nanoparticle. Methyl acrylate (MA) and ethylenediamine (EDA) are monomers that cause the formation of branches in PAMAM. The obtained particles were fully characterized in terms of particle size, polydispersity index, zeta potential, thermal behavior, morphology, pore diameter, pore volume, and specific surface area. The particle size of MSN-PAMAM-G3s showed around 187.71 ± 3.97 nm, with a polydispersity index of 0.17 ± 0.01 and zeta potential of 32.17 ± 1.30 mV. By reducing the ratio of drug to vehicle from 1 to 0.25, a significant increase in the EE% of 5-FU from 21.36 ± 0.70 to 43.12 ± 0.67 was observed. The release of 5-FU from the vehicle (5-FU@MSN and 5-FU@MSN-PAMAM-G3) was shown to be considerably higher in an acidic medium (pH = 5.5) in comparison to a neutral medium (pH = 7.4) (P-value<0.05). Furthermore, in both acidic and neutral conditions, 5-FU release was sustained from the vehicle rather than the 5-FU solution. Our research revealed that the MSN-PAMAM-G3 nanoparticles effectively regulated the encapsulation and release of 5-FU, providing pH-sensitive and sustained medication delivery. It is asserted that this nanocarrier has the potential to effectively deliver 5-FU to cancer cells.

Preparation of Co x Mg y Cu(1- x - y )Fe2O4 nanoparticles and their adsorption mechanism of methyl blue

A facile rapid-combustion process was introduced for preparing magnetic Co x Mg y Cu(1- x - y )Fe2O4 nanoparticles, and to enhance their specific surface area and saturation magnetization, the optimization involved adjusting the element proportion, calcination temperature, and solvent amount. The optimal element proportion of x:y:(1-x-y) for Co x Mg y Cu(1- x - y )Fe2O4 nanoparticles was 0.1:0.7:0.2, and the effects of solvent amount, and calcination temperature were also investigated. The average particle size and specific surface area of Co0.1Mg0.7Cu0.2Fe2O4 nanoparticles calcined at 400 °C with 25 mL absolute alcohol were 17.9 nm and 56.96 m2/g, respectively; while demonstrating a saturation magnetization of 8.5 emu/g. To solve the increasingly severe issue of water pollution, these nanoparticles were employed to efficiently treat dye wastewater containing methyl blue (MB). After fitting kinetic and isotherm models, the adsorption process of magnetic Co0.1Mg0.7Cu0.2Fe2O4 nanoparticles for MB dominated by chemisorption and was a multilayer adsorption process. The adsorption isotherm experiments revealed a remarkable maximum adsorption capacity of methyl blue, reaching 2255.7 mg/g, within the concentration range of MB from 400 to 4000 mg/L. The thermodynamic analysis indicated the spontaneity of the exothermic adsorption process. The studies on the effect of pH also led to satisfying results; while the residual adsorption capacity could still remain 91.2% initial adsorbance after 12 times recycle. The outstanding recycling ability, resistance to ionic strength, and pH resistance distinguished the magnetic Co0.1Mg0.7Cu0.2Fe2O4 nanoparticles among vast adsorbents. These results highlight the significant potential of these nanoparticles for treating dye wastewater.

Effect of silicon carbide powder on asphalt material properties and microwave-induced self-healing

Silicon carbide (SiC) powder, an excellent microwave-absorbing material, can serve as a filler in asphalt mixtures. This study compares the particle size distribution, phase composition, pore structure, specific surface area, and electromagnetic properties of SiC powder and limestone powder. Asphalt mastic and mixtures were prepared with SiC powder replacing mineral powder at ratios ranging from 0 % to 60 %. The study examines how differences in particle size gradation, mineral composition, pore structure, and specific surface area contribute to deformation resistance and improve mechanical properties through micro-level interlocking and cementation. Electromagnetic parameter variations affect microwave heating performance, with uniform distribution of absorbing fillers ensuring heating homogenization. SiC powder also enhances the self-healing index, reaching 74.4 %, and maintaining a maximum healing index of 68.1 % after four damage-healing cycles. These findings support the practical application of SiC powder in asphalt concrete, enhancing maintenance efficiency and advancing microwave heating for self-healing and hot recycling.

Enhancing reductive dechlorination of trichloroethylene in bioelectrochemical systems with conductive materials

The incorporation of conductive materials to enhance electron transfer in bioelectrochemical systems (BES) is considered a promising approach. However, the specific effects and mechanisms of these materials on trichloroethylene (TCE) reductive dechlorination in BES remains are not fully understood. This study investigated the use of magnetite nanoparticles (MNP) and biochars (BC) as coatings on biocathodes for TCE reduction. Results demonstrated that the average dechlorination rates of MNP-Biocathode (122.89 μM Cl·d−1) and BC-Biocathode (102.88 μM Cl·d−1) were greatly higher than that of Biocathode (78.17 μM Cl·d−1). Based on MATLAB calculation, the dechlorination rate exhibited a more significantly increase in TCE-to-DCE step than the other dechlorination steps. Microbial community analyses revealed an increase in the relative abundance of electroactive and dechlorinating populations (e.g., Pseudomonas, Geobacter, and Desulfovibrio) in MNP-Biocathode and BC-Biocathode. Functional gene analysis via RT-qPCR showed the expression of dehalogenase (RDase) and direct electron transfer (DET) related genes was upregulated with the addition of MNP and BC. These findings suggest that conductive materials might accelerate reductive dechlorination by enhancing DET. The difference of physicochemical characteristics (e.g. particle size and specific surface area), electron transfer enhancement mechanism between MNP and BC as well as the reduction of Fe(III) by hydrogen may explain the superior dechlorination rate observed with MNP-Biocathode.

The Characteristics of Adsorption of Di-n-Butyl Phthalate by Surface Sediment from the Three Gorges Reservoir.

Phthalic acid esters (PAEs), recognized as endocrine disruptors, are identified as predominant organic pollutants in the Three Gorges Reservoir (TGR). Di-n-butyl phthalate (DBP), a representative PAE, has been extensively studied for its sources, distribution and ecological risks. However, there are few studies on the adsorption of DBP by sediment from the TGR, and the adsorption characteristics of surface sediment on DBP are not clear. Therefore, based on the actual sediment contents and particle sizes in the TGR, the kinetics and isothermal adsorption characteristics of surface sediment on DBP were investigated in this study. The results showed that the equilibrium time was 120 min, the adsorption kinetics were more in line with the pseudo-second-order kinetic model, and the sediment in water from the Yangtze River exhibited a higher adsorption rate and maximum adsorption amount on DBP than that observed in deionized water. Additionally, a decrease in DBP adsorption was observed with increasing sediment content, while sediment particle size and specific surface area had a slight influence. Analysis using SEM, TGA and FTIR revealed that organic matter on the sediment surface significantly contributed to DBP adsorption. This study contributes valuable insights into the adsorption characteristics of DBP by the surface sediment from the TGR, providing a scientific foundation for understanding the migration and transformation of DBP in this critical reservoir in China.

AI-assisted deep learning segmentation and quantitative analysis of X-ray microtomography data from biomass ashes

X-ray microtomography is a non-destructive method that allows for detailed three-dimensional visualisation of the internal microstructure of materials. In the context of using phosphorus-rich residual streams in combustion for further ash recycling, physical properties of ash particles can play a crucial role in ensuring effective nutrient return and sustainable practices. In previous work, parameters such as surface area, porosity, and pore size distribution, were determined for ash particles. However, the image analysis involved binary segmentation followed by time-consuming manual corrections. The current work presents a method to implement deep learning segmentation and an approach for quantitative analysis of morphology, porosity, and internal microstructure. Deep learning segmentation was applied to microtomography data. The model, with U-Net architecture, was trained using manual input and algorithm prediction.•The trained and validated deep learning model could accurately segment material (ash) and air (pores and background) for these heterogeneous particles.•Quantitative analysis was performed for the segmented data on porosity, open pore volume, pore size distribution, sphericity, particle wall thickness and specific surface area.•Material features with similar intensities but different patterns, intensity variations in the background and artefacts could not be separated by manual segmentation – this challenge was resolved using the deep learning approach.

Alkali Extraction of Arsenic from Groundwater Treatment Sludge: An Essential Initial Step for Arsenic Recovery.

Arsenic (As)-bearing Fe(III) precipitate groundwater treatment sludge has traditionally been viewed by the water sector as a disposal issue rather than a resource opportunity, partly due to assumptions of the low value of As. However, As has now been classified as a Critical Raw Material (CRM) in many regions, providing new incentives to recover As and other useful components of the sludge, such as phosphate (P) and the reactive hydrous ferric oxide (HFO) sorbent. Here, we investigate alkali extraction to separate As from a variety of field and synthetic As-bearing HFO sludges, which is a critical first step to enable sludge upcycling. We found that As extraction was most effective using NaOH, with the As extraction efficiency increasing up to >99% with increasing NaOH concentrations (0.01, 0.1, and 1 M). Extraction with Na2CO3 and Ca(OH)2 was ineffective (<5%). Extraction time (hour, day, week) played a secondary role in As release but tended to be important at lower NaOH concentrations. Little difference in As extraction efficiency was observed for several key variables, including sludge aging time (50 days) and cosorbed oxyanions (e.g., Si, P). However, the presence of ∼10 mass% calcite decreased As release from field and synthetic sludges considerably (<70% As extracted). Concomitant with As release, alkali extraction promoted crystallization of poorly ordered HFO and decreased particle specific surface area, with structural modifications increasing with NaOH concentration and extraction time. Taken together, these results provide essential information to inform and optimize the design of resource recovery methods for As-bearing treatment sludge.

Particle Sizing and Surface Area Measurements: A Comparative Assessment of Commercial Air Permeability and Laser Light Diffraction Instruments

Six different commercial powders, finer than 45 μm, were used for examining the effects of particle characteristics on mean particle size and specific surface area. The measurements were carried out using the most commonly used air permeability- and laser light diffraction (scattering) techniques. As the air permeability method has been used as a benchmark for decades in the powder metallurgy (P/M) industry, the physical phenomena that govern the passage of gas through the powder bed under laminar flow conditions were also presented. The experimental data indicate that both methods give similar results for spherical powders. The advantage of laser light systems over gas permeameters is the ability to provide additional information on particle size distribution. Irregularly shaped powders should be analyzed by both techniques, relying on gas permeametry for surface area measurements and on laser light diffraction for the estimation of mean particle size and size distribution. Application of scanning electron microscopy as a complementary technique was found very helpful in the interpretation of data through visualization of individual particles.

Impact of annealing on Cu2O doped with Na/Co: Structural, optical, and electrochemical consequences

Impact of annealing on Cu2O doped with Na/Co: Structural, optical, and electrochemical consequences

Fabrication of Highly Sensitive Electrochemical Sensor Based on Chromium-Doped Ferrite Nanoparticles: Hybrid Graphene Nanosheets for the First Voltammetric Determination of Asenapine Maleate in Formulations and Human Plasma

Ferrite nanoparticles are interesting materials given their unique physical and chemical properties and wide applications. A novel electrochemical sensor based on a series of chromium-nano-ferrites {Fe3+[Fe2+Fe3+ (1-x)Cr3+ x ]O4; x (0.0–1.0} was fabricated for determination of Asenapine maleate (ASE.M). X-ray diffraction revealed the formation of crystallite nano-particles of lattice constant of (8.299–8.345 Å) with a single phase of cubic inverse spinel structures. Particle size and specific surface area were (9.10–27.60 nm) and (60–175 m2g−1) using Transmission electron microscopy and Brunnauer-Emmett-Teller (BET) analysis, respectively. Among this Cr x Fe(3−x)O4 series, (CrFe2O4; x = 1) was appeared to get the smallest particles size and highest BET surface area. The charge transfer resistance (RCT) of (2220, 1680, 765, and 490 Ω) were achieved for Cr x Fe(3−x)O4 NPs/CPE (x = 0.0, 0.4, 0.8, and 1.0), respectively. CrFe2O4 performance was then improved via incorporation of 2D-graphene atomic crystals in a new ferrite-graphene nanocomposite of [0.25%(w/w) CrFe2O4 NPs: 7%(w/w) graphene nanosheets]. The feasibility of this sensor is achieved for determination of ASE.M in brand Saphris® and local Asenapine pharmaceutical products. In addition, a wide linear concentration range of (6.5 × 10−9–1.0 × 10−6 M) with LOD value of 8.88 × 10−10 M were achieved in human plasma.

Production and applications of lead (II) oxide/poly(aniline-co-thiophene) composite materials for enhanced supercapacitor performance

In this work, a novel approach was employed to prepare and utilize lead (II) oxide and poly(aniline-co-thiophene) (PANI-co-PTh) composite materials as electrode materials for supercapacitors, marking the first instance of such utilization in the literature. PANI-co-PTh was synthesized in bulk through chemical polymerization, and the conducting polymers underwent comprehensive spectroscopic, physical, and microscopic characterization. Subsequently, the material, incorporating lead (II) oxide (PbO) as a composite, was employed as electrode materials in asymmetric-type supercapacitors. The main results indicate a clear relationship between the surface area of conducting polymers and their specific capacitance. Notably, PANI-co-PTh-6, possessing the highest surface area, demonstrated the highest specific capacitance. Particle size distribution and specific surface area for PANI-co-PTh-6 were determined as 130 μm and 64.76 m2g−1, respectively. The PbO@PANI-co-PTh-3 configuration exhibited the highest specific capacitance, reaching 294 Fg−1 at a 10 mVs−1 scan rate. Remarkably, during long-cycle experiments, this system demonstrated a capacity retention of 70.69% after 1000 cycles. The inaugural application of the PbO@PANI-co-PTh-3 supercapacitor showcased notable capacitance values, establishing a substantial foundation for future research endeavors in this field.

Effects of cavitation jet combined with ultrasound, alkaline hydrogen peroxide and Bacillus subtilis treatment on the properties of dietary fiber

In this study, we compared the effects of three methods on the structural, physicochemical, and functional properties of insoluble dietary fiber (IDF) in okara: cavitation jet plus ultrasonic treatment (UC), cavitation jet plus alkaline hydrogen peroxide treatment (HC), and cavitation jet plus fermentation with Bacillus subtilis (FC). Compared to UC-IDF, the two types of co-modified IDF showed significant differences in particle size and specific surface area. Structural analyses showed that HC-IDF had a porous structure and complex morphological structure, with a significant increase in the absorption peak area at around 3420 cm−1 and 1051 cm−1, and a significant decrease in thermal stability and crystallinity. Of the three treatments, HC most effectively enhanced the physicochemical and adsorption properties of IDF, including the emulsion stability (84.49% ± 3.5%), water-holding capacity (16.04 ± 0.05 g/g), glucose absorption capacity (53.17 ± 3.44 g/g), cholesterol absorption capacity (32.87 ± 0.89 mg/g), and nitrite absorption capacity (211.7 ± 0.17 μg/g). These results demonstrate the potential of HC-modified okara IDF as a valuable functional food ingredient. Therefore, the cavitation jet combined with alkaline hydrogen peroxide method has a good potential for application in the study of dietary fiber modification.

Influence of the Steel Slag Particle Size on the Mechanical Properties and Microstructure of Concrete

The present paper probes into the influence of the steel slag particle size on the mechanical properties and microstructure of concrete, with steel slag serving as the primary raw material. Steel slag with different particle sizes was selected as the partial substitute material for concrete by mechanical grinding. The influence of steel slag on the compressive strength, bending strength, and microstructure of concrete was determined by laser particle size analyzer, specific surface area analyzer, strength experiment, X-ray diffraction (XRD), and scanning electron microscope (SEM). The results show that mechanical grinding has significant effects on the particle size distribution and specific surface area of the steel slag. The optimal grinding time is 20 min and the specific surface area is 0.65 m2/g. D10, D50 and D90 are 0.91 μm, 16.57 μm and 46.40 μm, respectively. The steel slag with a fine particle size can better fill the pores in concrete and improve the compactness, thus enhancing the mechanical properties of concrete. The change in the steel slag particle size does not change the type of hydration products, but the smaller the particle size of steel slag, the better the gelling activity, the larger the hydration products, the denser the structure, and the better the mechanical properties. Therefore, the present study provides an important theoretical basis and practical guidance for the application of steel slag as an additive in the concrete industry.

Quantitative Analysis of the Physical Properties of Ti6Al4V Powders Used in a Powder Bed Fusion Based on 3D X-ray Computed Tomography Images.

The physical properties of Ti6Al4V powder affect the spreadability of the powder and uniformity of the powder bed, which had a great impact on the performance of built parts made by powder bed fusion technology. Micro-computed tomography is a well-established technique used to analyze the non-destructivity of the objects' interior. Ti6Al4V powders were scanned with micro-CT to show the internal and external information of all the particles. The morphology, particle size distribution, hollow particle ratio, density, inclusion, and specific surface area of the powder samples were quantitatively characterized, and the relationship of flowability with these physical properties was analyzed in this work. The research results of this article showed that micro-CT is an effective way to characterize these items, and can be developed as a standard method of powder physical properties in the future.

Effect of milled pegmatite quarry wastes powders on structure, microstructure and mechanical properties of pegmatite-based geopolymers

In this investigation, mechanical activation (MA) of pegmatite quarry wastes was perform via an eccentric vibratory mill to improve the geopolymeric reactivity. The MA at miscellaneous times (0 to 90 min) resulted in different activation degrees of samples with improved the fineness of particle size and specific surface area from 2.974 to 5.311 m2.g− 1. Geopolymer binders were synthesized by partly replacing the pegmatite quarry waste with 12.5 wt% of metakaolin. The activating solution used was a mixture of 10 M NaOH and Na2SiO3 solution with a volume ratio of 1:1. Reaction kinetics, compressive strength, water absorption, chemical (FT-IR, XRD, 27Al and 29Si MAS NMR), and microstructural (SEM/EDS and TEM) analyses were done to characterize the obtained geopolymer binders. The microstructural characterization reveals that undissolved/unreacted particles decreased while the non-bridge particles increased with pegmatite milled. Under SEM/EDS and TEM, fineness of pegmatite particles is highlighted by the formation of more reaction product. As a result, the compressive strength of geopolymer binders improved from 22.3 to 51.6 MPa for 0 to 60 min of milling. From these results, there is feasibility of valorising feldspathic (pegmatite) quarry wastes as alternative aluminosilicate precursors to develop environmentally-friendly geopolymer binders. The resulting binders with high-strength and low water absorption (≤ 8.6%) associated to minimization of CO2-emissions can be used as potential candidate in structural applications.

Influence of type, dispersion and amount of alumina on the properties of pressed refractories based on fused zirconia stabilized with ~10 % yttrium oxide

The influence of three types of α­alumina, which differ in dispersion — the specific surface area of particles of 1, 3, and 5 m2/g (two of them are active alumina) and their amount (up to 4 %) on the main properties of samples from fused ZrO2 stabilized with ~10 % Y2O3, fired at 1580 °C was studied. The optimum additive, as well as its amount (1 % alumina of lower dispersion), which ensures the production of fired samples with high property indicators, were determined: content of ZrO2 + HfO2 87.80 wt. %, Y2O3 9.20 wt. %, Fe2O3 0.15 wt. %, apparent density 4.71 g/cm3, open porosity 21.0 %, cold crushing strength 31 N/mm2, thermal shock resistance 13 heat cycle (1300 °C — water). No significant advantage of the Al2O3 additive in the form of active alumina has been established, so less dispersed alumina is preferred for economic reasons.&#x0D; As a result of the research performed at JSC “URIR named after A. S. Berezhnoy” institution, the technology of products made of fused ZrO2 stabilized with ~10 % Y2O3 was improved, which ensures the production of these products with a higher (although slightly) cold crushing strength and ~3 times higher thermal shock resistance (1300 — water) compared to similar characteristics of currently manufactured products. This can ensure a longer service life of refractories made of fused ZrO2 stabilized with ~10 % Y2O3 and with Al2O3 additive (due to their much higher thermal shock resistance compared to refractories of the same composition but without Al2O3 additive) in various thermal units at consumers’ facilities where this characteristic of refractories is most important.&#x0D; Based on the study results, regulatory documentation was developed and full­scale samples of industrial­format products were manufactured.

Using an economic method to prepare TiO2 from natural ilmenite for photodegradable dye removal

In this work, nanoparticles of ilmenite powder (47 nm) were prepared via ball-milling of natural ilmenite ore to enhance the specific surface area of particles. The photocatalytic activity of magnetically separable ilmenite nanoparticles was investigated in the degradation of methyl orange (MO) and methylene blue (MB). The Band gap of the ilmenite nanoparticles was calculated 3.05 eV. The photodegradation results show that ilmenite nanoparticles completely destruct MO and MB in 40 and 50 min under visible irradiation. In order to choose of optimum values of factors, the leaching process was optimized by applying a “Rotatable Central Composite Design” (CCD) technique. For preparing of required precursor, the grind ilmenite was crushed into small particles by ball milling method. In addition, in order to purifying the titanium slag, reduction process was carried out. Effective Factors on sulfuric acid process as follows leaching time, temperature, acid concentration and solid/liquid (S/L) ratio, were studied.

Investigating the impact of x‐ray computed tomography imaging on soluble organic matter in the Murchison meteorite: Implications for Bennu sample analyses

AbstractX‐ray computed tomography (XCT) is a valuable reconnaissance tool for three‐dimensional imaging and identification of distinct lithologies in extraterrestrial samples. It will be used as part of the preliminary examination of samples returned from asteroid (101955) Bennu by the Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS‐REx) mission. However, it must first be established whether x‐rays generated during XCT could degrade or alter the organic composition of the returned samples by radiolysis. To test this, we split a crushed sample of the Murchison CM2 meteorite, kept one portion as a control, and irradiated the other portion up to the maximum x‐ray dosage (~180 Gy) that a Bennu sample would experience during an XCT imaging experiment. We then extracted organic compounds from both splits and conducted (i) nontargeted soluble organic analyses to compare the chemical distributions of C‐, H‐, O‐, N‐, and S‐bearing species and (ii) targeted measurements to quantify the abundances of 96 individual soluble organic molecules that included protein amino acids, amines, carboxylic acids, hydroxy acids, carbonyl compounds, polycyclic aromatic hydrocarbons, alcohols, sugars, and N‐heterocycles. We found that XCT imaging of the Murchison meteorite had no measurable impact on the relative abundances or enantiomeric compositions of most of the soluble organic compounds targeted in this study. Elevated total abundances of several soluble organic compound classes were observed in the XCT‐scanned Murchison sample relative to the control. This is likely related to particle size heterogeneity and specific surface area differences between the sample aliquots used for the extractions, rather than a result of the x‐ray exposure. Assuming the samples returned from asteroid Bennu by OSIRIS‐REx have a similar composition to carbonaceous chondrites, these data provide confidence that XCT will not significantly alter their soluble organic compositions.