Preparation Of Mg Research Articles

Birnessite-MnO2 nanostructures synthesized by facile hydrothermal and green method for dye degradation application

Water contamination resulting from the presence of organic dye pollutants in the ecosystem is a significant issue in the 21st century, that requires urgent resolution. Utilizing an effective nanocatalyst for the removal of dyes from water is a viable solution to address this problem. In this study, we proposed two distinct approaches for synthesizing δ-MnO2 nanostructures: an environmentally friendly, “green” method (MG) and a “cost-effective” hydrothermal method (MH). The leaf extract of Clinacanthus nutans was used for the preparation of MG, while MnSO4 was used for MH as a reducing agent, along with KMnO4, with the reaction time fixed at 90 °C. X-ray diffraction analysis confirmed that both approaches yielded δ-MnO2 nanostructures with a monoclinic Birnessite phase. The MG sample displayed a coagulated nanoflake-like morphology, as observed in FESEM images. On the other hand, the MH sample exhibited a distinct nanoflower morphology. The materials' optical properties were investigated using UV–visible spectra analysis, revealing direct bandgap energies of 2.2 eV and 2.58 eV for the MG and MH, respectively. The surface area of the MG sample was found to be higher as compared to the MH nanoflower, showcasing a mesoporous structure. XPS analysis was employed to determine the oxidation states of the elements. The effect of varying pH levels on the degradation of Methyl Orange dye by the two nanocatalysts was investigated. The results demonstrated that acidic pH led to higher decolouration efficiency, particularly notable for the MG nanocatalyst. Consequently, this study illustrates that the green δ-MnO2 nanocatalyst effectively degrades methyl orange dye under acidic conditions through photocatalysis.

Schematic diagram illustrating the corrosion reaction in Mg–Li–Al–Ca alloy with and without β-Li phase

The effect of Li on the microstructure and corrosion behavior of extruded Mg-xLi-3Al-0.4Ca (x = 4,5,6,7) alloys were investigated by hydrogen evolution, potentiodynamic polarization measurement and electrochemical impedance spectroscopy measurement. The single-phase 4Li alloy with the largest α-Mg grain size and the strongest basal texture intensity exhibits the best corrosion resistance in 3.5 wt% NaCl solution. The duplex 6Li and 7Li alloys contain a protective LiOH film in the corrosion products, giving them better corrosion resistance than 5Li alloy. This study provides a new insight for the design and preparation of Mg–Li alloys with high corrosion resistance.

PVA-assisted preparation of Mg(OH)2/MgO nanostructures from seawater bittern through precipitation method

PVA-assisted preparation of Mg(OH)2/MgO nanostructures from seawater bittern through precipitation method

Preparation of Mg, Ca, or Sr-included mesoporous silica from glass bottle waste for recovery of rare earth metal elements

This paper suggests new uses for colored waste bottle glass. Silica was hydrothermally extracted and the mesoporous silica including alkali-earth metal elements was synthesized which have great ion exchangeability for rare earth metal cations.

Retracted: Preparation of Mg2Ni Hydrogen Storage Alloy Materials by High Energy Ball Milling

Retracted: Preparation of Mg₂Ni Hydrogen Storage Alloy Materials by High Energy Ball Milling

High-Throughput, In Situ Preparation of Mg–Al Hydrotalcites and Tandem Self-Condensation of Cyclopentanone Integrated via the Ball-Milling Process

High-Throughput, In Situ Preparation of Mg–Al Hydrotalcites and Tandem Self-Condensation of Cyclopentanone Integrated via the Ball-Milling Process

Preparation of Mg(OH)2 Microsphere by Gas-Continuous Impinging Streams for Congo Red Absorption Removal

Preparation of Mg(OH)2 Microsphere by Gas-Continuous Impinging Streams for Congo Red Absorption Removal

Preparation of Mg–6Zn–1La-0.5Zr alloy sheet with excellent mechanical properties and electromagnetic interference shielding effectiveness by extrusion plus rolling

In the field of specialty electronics and communications, there is a critical demand for magnesium (Mg) alloy sheets that possess exceptional mechanical properties and electromagnetic interference shielding effectiveness (EMI SE). This paper aims to develop a cost-effective and straightforward process for preparing a research proposal that combines excellent mechanical properties and EMI SE. After undergoing extrusion treatment, the Mg–6Zn–1La-0.5Zr alloy demonstrates an apparent bimodal microstructure, with an average grain size of approximately 2.55 μm. Subsequently, following a 37% rolling treatment, the grain size increases to about 5.29 μm. This increase in grain size is attributed to grain growth resulting from holding prior to the multi-pass rolling treatment. Notably, the Mg–6Zn–1La-0.5Zr alloy, subjected to extrusion and 75% rolling treatment, exhibits remarkable mechanical properties and EMI SE, with ultimate tensile strength (UTS), yield strength (YS), and elongation (EL) values of 337.5 MPa, 227.3 MPa, and 12.5%, respectively. Furthermore, the EMI SE ranges from 79 dB to 110 dB within the frequency range of 30–1500 MHz. The exceptional mechanical properties are attributed to the synergistic effects of various strengthening mechanisms, including grain boundary strengthening, second phase strengthening, dislocation strengthening, heterogeneous deformation-induced strengthening, and texture. Similarly, the superior EMI SE is attributed to the alloy's higher electrical conductivity, strong basal texture, and uniformly diffused second phase.

The design and preparation of Mg and Zn co-doped carbon nitride with enhancing photocatalytic degradation efficiency for methylene blue

Carbon nitride (g-C3N4) is a potential material that can be used for the treatment of the wastewater contains organic dyes. However, the photocatalytic efficiency of g-C3N4 is limited by the wide band gap and fast recombination of photon-generated carriers. In this work, the co-doped with Mg and Zn of MgZn0.07-g-C3N4 was designed and prepared to enhance the photocatalytic efficiency. The co-doped Mg and Zn shorted the band gap of g-C3N4 from 2.74 eV to 2.50 eV. Interestingly, according to the DFT calculation, a Zn-bridge is formed between the interlayers of g-C3N4. The Zn-bridge reduces the electron localization and prolongs the existence time of photon-generated carriers. The as-prepared MgZn0.07-g-C3N4 was applied for the photodegradation of methylene blue. The degradation ratios and photodynamic parameter of MgZn0.07-g-C3N4 are higher than that of g-C3N4 and Mg-g-C3N4 (29.51 × 10−3 min vs 8.00 × 10−3 min).

Efficient preparation of magnesium bicarbonate from magnesium sulfate solution and saponification-extraction for rare earth separation

To realize the recycling of magnesium sulfate wastewater in the hydrometallurgy and separation process of Baotou mixed rare earth (RE) concentrate, the research on preparation of magnesium bicarbonate (Mg(HCO3)2) solution from magnesium sulfate solution by CO2 carbonation, extraction separation and transformation of RE sulfate solution by saponified HDEHP was investigated. The key influencing factors and carbonation mechanism in the preparation of Mg(HCO3)2, and the distribution of RE, calcium and magnesium elements in the saponification extraction were systematically studied. The results show that the conversion of Mg(HCO3)2 during carbonation is inhibited by calcium sulfate, but promoted by increasing the concentration of magnesium sulfate and decreasing the carbonation temperature. Under the optimized conditions, Mg(HCO3)2 solution with impurities (such as Fe, Al and Si) of less than 15 mg/L is prepared stably and efficiently, and the conversion rate of Mg(HCO3)2 is more than 95%. After multi-stage cascade extraction of RE sulfate solution, the RE extraction recovery is greater than 99.5%. Calcium sulfate crystals do not precipitate during the process, and the raffinate phase is magnesium sulfate solution that is used for the preparation of Mg(HCO3)2 solution.

Synthesis and characterization of magnesium hydroxide nanoparticles via sol-gel

The magnesium hydroxide (Mg (OH)2 nanoparticles (NPs) were prepared using the sol-gel method and presented its results in this work. Various characterization methods have been used to confirm the successful preparation of Mg (OH)2 NPs. The XRD analysis exhibited the hexagonal structure of the sample. FT-IR spectrum revealed the presence of metal-oxygen stretching of prepared magnesium hydroxide NPs. The SEM analysis shows that the synthesized Mg (OH)2 NPs were clustered with a rough stacked surface. From the absorption peak obtained through UV-Vis spectroscopy, the bandgap energy of Mg (OH)2 NPs was calculated as 2.70 eV.

A Hands-on Guide to the Synthesis of High-Purity and High-Surface-Area Magnesium Oxide

In this study, magnesium nitrate, chloride or sulphate were used in the synthesis of Mg(OH)2, the precursor of MgO. It was found that the counter ion strongly influences the purity of the Mg(OH)2, as well as the specific surface area of the obtained MgO. The latter is also strongly influenced by the calcination temperature. The choice of the precipitating agent can lead to the introduction of K+ or Na+ ions and hence NH3 (aq) is the best choice. A multistep precipitation procedure of Mg(OH)2 was proposed to lower the concentration of typical impurities (Fe, Ni and Mn) found in commercial p.a. purity Mg(NO3)2. The effect of the number of portions of water used for washing of Mg(OH)2 on the purity of the final product has also been investigated in detail. The stages of formation of grains of Mg(OH)2 and their subsequent thermal decomposition was described together with determination of the introduction of new impurities into the material. Large scale (1500 g) preparation of Mg(OH)2 with an improved purity was performed and described. Therefore, this study explains what measures should be taken to obtain pure magnesia catalysts and is a valuable resource for catalytic research in which magnesia is used.

Preparation of Mg, Ca, Sr and Ba-based silicate as adsorbent of free fatty acid from crude palm oil

In present work, alkaline silicate based on Ba, Ca, Mg and Sr were used as adsorbent for free fatty acids (FFA) removal to improve the quality of shelf-life in crude palm oil (CPO). Environmentally friendly alkaline silicate was successfully prepared using low-cost and facile preparation by sol-gel method annealed at 600, 700 and 800 °C for comparison. Several characterization namely scanning electron microscope (SEM), x-ray diffraction (XRD), fourier-transform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller (BET) surface area were used to characterize the alkaline silicate morphology, crystallinity, functional group and porosity, respectively. Based on experimental result, the FFA removal and carotene value of CPO were evaluated, it is found that MgSiO 3 annealed at 600 °C demonstrate the highest FFA removal percentage of 95% and carotene can be preserved around 45% due to high surface area of 420.2 m 2 /g, which is superior compared to BaSiO 3 , CaSiO 3 and SrSiO 3 . This can be due to the high surface area with large adsorption sites of granular structure of MgSiO 3 and crystallinity. Thus, this finding gives new pathways of alkaline silicate annealed at low temperature can be used efficiently for future biodiesel applications.

Preparation of Mg and Ce nanomaterials and their degradation of dye wastewater

Preparation of Mg and Ce nanomaterials and their degradation of dye wastewater

Co-precipitation of nano Mg–Y/ZrO2 ternary oxide eutectic system: Effects of calcination temperature

In the family of inorganic nanomaterials, zirconia is a highly promising functional ceramic with a high refractive index, hardness, and dielectric constant, as well as excellent chemical inertness and thermal stability. These properties are enhanced in nano-zirconia ceramics, because nanopowders have a small particle size, good morphology, and uniform and dispersive distribution. In this study, a co-precipitation process was proposed to synthesise highly dispersed MgO–Y2O3 co-stabilized ZrO2 nanopowders. The effects of different calcination temperatures on the crystallisation degree and particle dispersion of zirconia nanopowders were characterised by X-ray diffraction (XRD), thermogravimetry-differential scanning calorimetry (TG-DSC), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption using the Brunauer–Emmett–Teller (BET) theory, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM). The optimum synthesis conditions were obtained as follows: 6 h of high-energy planetary grinding and calcination at 800 °C in an electric furnace. Under these optimum conditions, the average particle size of the prepared powder was 28.7 nm. This process enriches the literature on the controllable preparation of Mg–Y/ZrO2 nanopowders obtained by the co-precipitation method.

Preparation and Properties of Mg(OH)2 Whiskers by Ion Exchange Resin Method

Mg(OH)2 whiskers were successfully prepared under mechanical stirring with D301 ion exchange resin and Mg(NO3)2. The products were systematically characterized by testing settling ratio, turbidity, and analyzing SEM, FT-IR. The results showed that Mg(OH)2 prepared with 0.05 or 0.1 mol/L Mg(NO3)2 had excellent dispersion, and the settling ratio was close to 100 % after 360 min; The time extension was extremely helpful to improve the dispersion; The dispersion of product was correspondingly good under pH value of about 9. The products synthesized with different concentrations and reaction time could reach nanoscale, and the product obtained using 0.05 mol/L Mg(NO3)2 for 4 h had whisker structure with a length of 10 im and had a lipophilicity. FT-IR analysis showed the product included some functional groups or fragments from the resin, which had a positive modification effect on the products. The preparation of Mg(OH)2 whisker with resin as raw material is simple, green, and environmentally friendly, which is worthy of further application.

Preparation of Mg–Nd Alloys by Magnesiothermic Reduction in Molten Salt

Preparation of Mg–Nd Alloys by Magnesiothermic Reduction in Molten Salt

Preparation of Mg, Ca, Sr and Ba-Based Silicate as Adsorbent of Free Fatty Acid from Crude Palm Oil

Preparation of Mg, Ca, Sr and Ba-Based Silicate as Adsorbent of Free Fatty Acid from Crude Palm Oil

Effect of Biodegradable Magnesium Alloy Biomaterials on Neurological Rehabilitation of Cerebrovascular Diseases

Elements such as Mg, Zn, and Sr were selected in this research, and the Zn content was set to 3.8%. The relative content of Sr was determined to be 1.0% after the influence of Sr on the microstructure and properties of Mg–Sr alloys was explored. Then, the Mg–3.8Zn–1.0Sr alloy material was prepared, and the uniformity and tensile strength of the material were further increased through solution treatment and aging treatment. When the biodegradation test was performed and the biocompatibility of the material was analyzed, the material was used in the rehabilitation treatment of intracranial wide-necked aneurysms. In the test, the addition of Zn and Sr helped to form the passivation film on the surface of the magnesium alloy, and the second phase of the cross-section generated can prevent the expansion of corrosion. The corrosion rate continued to decrease with time (P < 0.05), and the pH of the DMEM solution participating in the experiment also showed a rising trend (P < 0.05). The hemolysis rate of Mg–3.8Zn–1.0Sr (wt.%) alloy was only 4.54%, indicating that it had a good anti-hemolytic function and showed low toxicity in the cytotoxicity test of the extract. The lateral wall type aneurysm model was constructed in white rabbits, and Mg–3.8Zn–1.0Sr (wt.%) was set as the stent material. Postoperative follow-up showed that the material implantation in the model promoted the complete occlusion of the aneurysm and the unobstructed common carotid artery. The molybdenum target test showed that the prepared magnesium alloy stent gradually degraded with time, and most of it degraded after 12 months. Moreover, clinical trials of intracranial wide-necked aneurysms suggested that alloy stent materials based on the preparation of Mg–3.8Zn–1.0Sr can help patients realize complete embolization. Although there was residual tumor, no recurrence of aneurysm occurred in the re-examination, which proved that the stent material was effective.

Preparation of Pt supported on mesoporous Mg–Al oxide catalysts for efficient dehydrogenation of methylcyclohexane

Hydrogen energy, characterizing by high-energy density, non-pollution and renewability, is regarded as an ideal clean green energy, and the chemical hydrogen storage is an optimal strategy to realize its large-scale utilization. In this study, to enhance the hydrogen evolution rate in the dehydrogenation of methylcyclohexane (MCH), Pt supported on Mg–Al oxide catalysts were prepared and the effects of the co-precipitation reaction time during the preparation of Mg–Al hydrotalcite on their structural properties were studied in detail. The results showed that both the pore diameter and Pt dispersion were increased after prolonging the precipitation reaction time. During the dehydrogenation of MCH, these resultant catalysts presented high activity and good stability: hydrogen evolution rate reached up to 1892 mmol·gPt−1 min−1 at 623 K and the conversion was still held at 92% after 218 h. Of course, a slight decrease on the conversion during the dehydrogenation reaction was also observed, which was mainly attributed to the aggregation of Pt particles at high temperature.