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Novel CoNi7O8/MnO2 supported on Ni foam presented excellent catalytic activity toward PMS activation, with 100% MB removal achieved within 15 min.

Co3S4 nanosheets on Ti mesh (Co3S4/TM) synthesized by a liquid phase reaction, subsequent anion exchange reaction and final hydrothermal vulcanization with Co-MOF as a precursor exhibit superior hydrazine sensing performance.

Phosphate coating is a commonly used anti-corrosion coating for NdFeB magnets, but its application is hindered by the intrinsic porosity and adverse impact on magnetic performance during the conventional chemical conversion process. Here, a compact magnesium phosphate coating with high protective efficiency has been successfully fabricated on the surface of NdFeB magnets. The surface properties, corrosion resistance and magnetic performance were investigated in detail. It is found that the quality of magnesium phosphate coating significantly depends on the deposition temperature. The coated sample deposited at 60 °C possesses the highest impedance value and protective efficiency (94.25%), because this temperature is appropriate for sufficient deposition of magnesium phosphate crystals (MgHPO4·3H2O) and can avoid defects induced by the excess growth of (021) plane. In addition, the magnesium phosphate coatings fabricated by electrochemical cathodic method exhibits no prejudice to the magnetic performance of NdFeB magnets. The superiority in corrosion resistance and magnetic performance of electrodeposited magnesium phosphate coating provides tremendous application prospect for developing protective coating of sintered NdFeB magnets.

Exploiting cost-effective, highly efficient and stable alkaline electrocatalysts is a great challenge for the hydrogen evolution reaction (HER). Herein, NiMoO4 and CoFe layered double hydroxide (CoFe LDH) with poor crystallinity were successively deposited on Cu nanowire (Cu NW) grown on Cu foam by a two-step electrodeposition process, which was verified by XRD, Raman, ATR-FTIR, XPS, SEM, TEM and HRTEM characterizations. The HER performance measurement in 1.0 M KOH solution showed the optimal CoFe LDH-60 s/NiMoO4/Cu NW/Cu foam sample demonstrated prominent alkaline HER activity and long-term durability with an ultralow overpotential of 45 mV at −10 mA cm−2 and a Tafel slope of 94.0 mV dec−1, superior to the recently reported transition metal-based electrocatalysts. Further study clarified that the remarkable alkaline HER performance could be attributed to the strong synergistic effect between CoFe LDH-60 s and NiMoO4 in favor of water adsorption/activation and optimizing hydrogen adsorption, and providing plentiful exposed active sites as well as an enhanced electron transfer process offered by the unique 1D nanostructure with Cu nanowire as the core. This work can provide a guidance for designing a highly active and stable electrocatalyst for hydrogen production.

A heterostructure α-Fe2O3/SiC (FS) was designed by depositing α-Fe2O3 nanotubes on the surface of SiC through a facile hydrothermal method. Microstructure and photocatalytic activity of the hybrid ...

In this article, a new process for treating steel slag and CO2 simultaneously and preparing calcium carbonate, metallic iron, and glass ceramics without wastewater or gas production is proposed. The reduction of iron and preparation of diopside glass ceramics are studied in this paper, and the results show that the carbon thermal reduction product of the original slag does not reach its melting point, and the slag and iron are well separated in the samples containing the leached steel slag and added silica. Part of the parent glass is converted into a glass ceramic after heat treatment, and the crystalline phases of samples are melilite, diopside, and partial melilite, and diopside and anorthite, respectively. The crystallization activation energy of the best sample in this article is E = 660.664 kJ/mol. The Avrami indices calculated at different heating rates are all less than 3, which indicates that the crystallization mode of the glass involves surface crystallization. This finding is consistent with the results for the prepared glass ceramics.

A hollow–structured NiCo Hydroxide/carbon nanotube composite is prepared using a facile epitaxial growth route based on the construction of a new 3D hard template and a subsequent etching treatment. With a controlled etching procedure, the hard template Cu2O nanoparticles gradually dissolve, which results in the formation of a hollow structured NiCo hydroxide/carbon nanotube composite. Owing to a synergetic contribution from the hollow structured NiCo Hydroxide and the intersected carbon nanotube network, the NiCo hydroxide/carbon nanotube composite electrode exhibits a significant enhancement in structural stability and displays a higher specific capacitance (1896 and 1479 F g−1 at 1 and 40 A g−1, respectively) in comparison with that of the NiCo hydroxide. An asymmetric supercapacitor consisting of hollow structured NiCo Hydroxide/carbon nanotube composite shows a high specific capacitance of 139.3 F g−1 at 1 A g−1, a maximum energy density of 37.9 Wh kg−1, and a power density of 7005 W kg−1. The device also maintains 91.6% of its initial specific capacitance and a coulombic efficiency close to 100% after 12,500 cycles at 6 A g−1. This superior performance suggests that the prepared hollow structured Hydroxide/carbon nanotube composite has potential for applications as an electrode material in high–performance supercapacitors.

We synthesized a flower-like Ni–Mn–S structure on Ti mesh (Ni–Mn–S/TM) as a monolithic sensing platform by a facile electrodeposition method. The phase composition and surface morphology of the as-prepared samples were characterized by XRD, XPS, SEM, TEM and HRTEM. The electrodeposits displayed a unique hierarchical nanosheet structure. Mn incorporation remarkably modulated the surface morphology of Ni–S on TM. This flower-like structure could increase the active surface area, providing more active sites for the electrocatalytic reaction. Electrochemical measurement demonstrated that Ni–Mn–S/TM exhibited good response to glucose in the range of 12 μM to 3.5 mM with a high sensitivity of 860.8 μA mM−1 cm−2. The binder-free Ni–Mn–S/TM electrode also presented good anti-interference ability, reusability and stability. This work gives a new avenue to improve the glucose sensing performance of nickel sulfide and even other nanomaterials.

Three-dimensional interconnected Co(OH)2 nanosheets (Co(OH)2 NS) were electrodeposited onto a Ti mesh (TM) surface, which was demonstrated by XRD, Raman spectroscopy, XPS and SEM characterization. The electrochemical sensing performance of the Co(OH)2 NS/TM toward hydrazine was investigated by cyclic voltammetry and amperometric techniques in a 0.1 M NaOH aqueous solution. The as-prepared Co(OH)2 NS/TM with an electrodeposition time of 10 min exhibited prominent capacity to detect hydrazine with a wide linear range from 5 μM to 3.0 mM and limit of detection (LOD) of 1.98 μM. Co(OH)2 NS/TM electrodes also showed a high sensitivity of 2793.9 μA mM−1 cm−2, excellent selectivity, reproducibility, appreciable stability with a RSD less than 3.5%, as well as the high recovery of hydrazine in real samples, indicating its potential application in real sample analysis.

Developing a cost-effective and efficient bifunctional electrocatalyst with simple synthesis strategy for hydrazine sensing and H evolution reaction (HER) is of utmost importance. Herein, a three-dimensional porous Cu-doped metallic Ni coating on Ti mesh (Ni(Cu) coating/TM) was successfully electrodeposited by a facile electrochemical method. Electrochemical etching of the electrodeposited Ni(Cu) coating with metallic Ni and Cu mixed phase on a Ti mesh contributed to the formation of a three-dimensional porous Cu-doped metallic Ni coating. Owing to the large specific surface area and enhanced electroconductivity caused by the porous structure and Cu doping, respectively, the developed Ni(Cu) coating/TM exhibited superior hydrazine sensing performance and electrocatalytic activity toward hydrogen evolution reaction (HER). The Ni(Cu) coating/TM electrode presented a good sensitivity of 3909 μA mM−1 cm−2 and two relatively broad linear ranges from 0.004 mM to 2.915 mM and from 2.915 mM to 5.691 mM as well as a low detection limit of 1.90 μM. In addition, the Ni(Cu) coating/TM required a relatively low HER overpotential of 140 mV to reach −10 mA cm−2 and exhibited robust durability in alkaline solution. The excellent hydrazine electrooxidation and HER performance guarantee its promising application in hydrazine detection and energy conversion.

The recycling of metallic iron is commonly the first step to fully use the converter slag, which is the biggest waste discharge in the steelmaking process. This study presents a proposed improved process of separating metallic iron from vanadium-bearing converter slag more efficiently. The mineralogical and morphological characteristics of the converter slag were first investigated, and the results showed that most of the iron was incorporated in the spinel and olivine. Grinding, sieving and magnetic separation were combined to recover metallic iron from the converter slag, and yielded approximately 41.5% of iron in which the iron content was as high as 85%, and the non-magnetic concentrate contains 8.56% vanadium with a yield of 95.3% and 8.63% titanium with a yield of 85.3%. The magnetic part can be used as the raw materials in the steel making process, whereas the non-magnetic part can be used as the raw materials for the further extraction of vanadium.

A co-recovery process used to extract iron, chromium, and vanadium in the form of chromium–vanadium-bearing metallic iron from vanadium tailings via a semi-molten reduction-magnetic separation meth...

Cost-effective and low-toxicity of MnO2 is regarded as a promising alternative to Co-based catalyst for peroxymonosulfate (PMS) activation to degrade recalcitrant organic pollutants. However, the sluggish Mn(IV)/Mn(III) redox cycling and limited specific surface area greatly hampered its wide application. To solve this challenge, a mesoporous γ-Fe2O3@MnO2 magnetic catalyst with SiO2 assistance (s-γ-Fe2O3@MnO2) was synthesized. Physicochemical characterization confirmed part MnO2 was coated on γ-Fe2O3 surface while the other existed independently. Furthermore, BET surface area of s-γ-Fe2O3@MnO2 was more than two times that of the counterpart without SiO2 assistance (ws-γ-Fe2O3@MnO2). s-γ-Fe2O3@MnO2 exhibited enhanced PMS activation capacity with 97.6% phenol removal efficiency within 80 min, superior to other samples. Various influencing parameters on phenol oxidation were optimized. Reactive oxygen species (ROS) scavenging experiment and electron paramagnetic resonance (EPR) validated co-existence of hydroxyl radicals (·OH) and sulfate radicals (SO4·−) as well as singlet oxygen (1O2) during PMS activation. However, phenol degradation was a non-radical oxidation process dominated by 1O2. A rational reaction mechanism was proposed. Fe(II) promoted Mn(IV)/Mn(III) redox cycling and the enlarged surface area derived from SiO2 mediated templating synthesis were responsible for the enhanced phenol degradation. This strategy can give a guidance for synthesis of highly efficient catalyst for sewage remediation.

Take into account the fact that the natural rutile utilized for the production of titanium dioxide pigment through chloride process is desperately lacking worldwide especially in China, an attempt was exploited for extracting synthetic rutile from Yunnan ilmenite concentrate with hydrochloric acid pressure leaching process. The leaching parameters for one step leaching process were investigated. The results shown that the optimum condition is leaching temperature of 413 K (140 °C), acid concentration of 20 pct HCl, leaching time of 4 hours and liquid/solid mass ratio of 8:1. A two steps leaching process was also suggested to reutilize the leaching liquor which with a high content of HCl. The results showed that the content of HCl decreased from 135 to 75 g/L, total iron increased from 44.5 g/L to about 87.6 g/L, and the liquid/solid mass ratio decreased to 5:1 with a two steps leaching process. The leaching product produced through a two steps leaching process shows a pure golden red with a high content of titanium (92.65 pct TiO2), a relatively low content of calcium (0.10 pct CaO) and magnesium (0.12 pct MgO), but high content of silicon (5.72 pct SiO2).

Hierarchical NiO/Ni

Magnetic BiOBr/SrFe12O19 nanosheets were successfully synthesized using the hydrothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and UV-visible diffused reflectance spectra (UV-DRS), and the magnetic properties were tested using a vibration sample magnetometer (VSM). The as-produced composite with an irregular flaky-shaped aggregate possesses a good anti-demagnetization ability (Hc = 861.04 G) and a high photocatalytic efficiency. Under visible light (&lambda, &gt, 420 nm) and UV light-emitting diode (LED) irradiation, the photodegradation rates of Rhodamine B (RhB) using BiOBr/SrFe12O19 (5 wt %) (BOB/SFO-5) after 30 min of reaction were 97% and 98%, respectively, which were higher than that using BiOBr (87%). The degradation rate of RhB using the recovered BiOBr/5 wt % SrFe12O19 (marked as BOB/SFO-5) was still more than 85% in the fifth cycle, indicating the high stability of the composite catalyst. Meanwhile, after five cycles, the magnetic properties were still as stable as before. The radical-capture experiments proved that superoxide radicals and holes were main active species in the photocatalytic degradation of RhB.

At present, dye wastewater is the most difficult industrial wastewater to treat. Photocatalytic degradation of dye wastewater under visible light irradiation is the most potential method. Magnetic photocatalytic material is a very good choice because of its easy separation and without secondary pollution. Based on a comparative study between α-Bi2O3 and β-Bi2O3, β-Bi2O3/SrFe12O19 magnetic photocatalyst was prepared to aim at rhodamine B(RhB) photodegradation. The photodegradation rate of RhB reaches 92.97% after 150 min photocatalytic reaction under visible light irradiation. We hope that this work can provide a reference for dye wastewater treatment.

Sustainable design aims at environmentally friendly, socially acceptable and economically acceptable. Sustainable design method in life cycle stages takes into account environmental, economic and social factors. It is an important means for industrial manufacturing to save resources and energy, reduce waste and improve quality. The sustainable design method is an effective design method for enterprises to reduce the cost of products, increase the added value and competitiveness. In this paper, the sustainable design method is analyzed, and the product sustainable design evaluation system and the process of product design innovation are constructed. The product sustainable design method is used in the design case, further research and application are carried out, and good results are obtained. The research in this paper provides a basis and method support for the sustainable design of enterprises, which is of great significance and application value for the development and realization of new products and the sustainable design and manufacture of products.

Rechargeable all-solid-state batteries have better safety and higher energy density than the commercial rechargeable Li-ion batteries with organic liquid electrolytes. However, it is still quite challenging to develop a thin, flexible and high Li-ion conductive solid electrolyte for all-solid-state batteries. Here we develop a flexible poly(ethylene oxide) (PEO)-based composite electrolyte with high ionic conductivity of 1.3 × 10−4 S cm−1 at 30 °C. Fast Li-ion conductive NASICON Li1.3Al0.3Hf1.7(PO4)3 (LAHP) powders with a high bulk ionic conductivity of 7 × 10−4 S cm−1 at 25 °C are added into PEO-LiTFSI electrolyte to increase the total Li-ion conductivity of the electrolyte. Solid nuclear magnetic resonance (NMR) has been employed to analyze the Li-ion conducting mechanism of the electrolyte. Moreover, the composite electrolyte PEO-LiTFSI-20LAHP with a more amorphous component shows better electrochemical stability than the PEO-LiTFSI electrolyte. The performance of the electrolyte PEO-LiTFSI-20LAHP is also tested in different all-solid-state cells; the composite membrane blocked lithium-dendrite growth, which increases the cycling life of all-solid-state cells.

The traditional aeration leaching process for the upgrading of reduced ilmenite is extremely sluggish and needs significant improvements in its efficiency. An improved aeration leaching process which comprises reduction, aeration with a catalyst, wet magnetic separation, and further leaching, was used for the preparation of synthetic rutile in the present study. The effects of NH4Cl concentration, HCl addition, 9, 10-anthraquinone-2, 6-disuifonic acid, disodium salt (catalyst AQ-2, 6) addition, temperature, stirring speed, liquid/solid mass ratio, and leaching time on the metallic iron removal rate from the reduced ilmenite were studied. The bench-scale experiment results reveals that the aeration leaching efficiency can be significantly improved by adding 2.0% HCl or 0.2% AQ-2, 6 in NH4Cl solution, and the fine magnetite (Fe3O4) particles can be steadily produced with the addition of AQ-2, 6. The pilot-scale experiment results show that the synthetic rutile can be upgraded to ∼86% of TiO2 with 0.2% AQ-2, 6 addition within 8 h of aeration leaching, and the recovery of TiO2 can be improved by 3% when replace the traditional hydrocyclones with the swet magnetic separation. The improved process can not only shorten the leaching time but also possible to improve the quality of the products by accurate classification.

There is an abundance of vanadium-titanium magnetite in Panzhihua, China, which contains more than 8.73 × 108 tons of TiO2 accounting for 90.6% of the national reserves. To fully utilize Panzhihua titanium resources, many processes were proposed. The development and utilization of vanadium-titanium magnetite resource have extremely vital significance. However, its current use of technology is inadequate. This article is a review on techniques to make comprehensive use of vanadium-titanium magnetite, especially in the titanium extraction, and the existing problems are also introduced. The authors predict its possible tendency of development of comprehensive utilization of vanadium-titanium magnetite in the future.

Chlorination process is a clean and efficient way to manufacture of titanium dioxide pigment. However, the limited natural rutile promotes the investigation on the upgrading of ilmenite ore into titanium-rich materials. The principle and producing situation of some production methods of TiO2-rich materials preparation for the chlorination process are discussed. The advantage and disadvantage of the Reduction smelting produces titaniferous slag, Carbothermal reduction-nitridation, Acid leaching, and Reductive leaching produce synthetic rutile are also summed in this paper. This paper presents a review of these technologies and carbothermal reduction-nitridation method is recommended to deal with Panzhihua ilmenite ore to meet the needs of the titanium dioxide pigment production by chlorination process.

The fusing temperature and the viscosity are important physical properties of high titanium slag. The Einstein-Roscoe equation was used to study the thermodynamic simulation of high titanium slag via FactSage software. The effects that the MnO had on the fusing temperature and the viscosity of high titanium slag were studied, and the reliability of the thermodynamic simulation method is verified by experiments. The results showed that the fusing temperature and the viscosity of high titanium slag decreased when the MnO content increased. The fusing temperature of high titanium slag was 1626.17∼1691.24 °C. After the high titanium slag was completely melted, the viscosity of high titanium slag was 86∼127 mPa · s. When the temperature was lower than the fusing temperature, the high titanium slag precipitated into solid-phase particles. The amount of precipitation increased when the temperature decreased, which in turn increased the viscosity of the high titanium slag.

The recovery of alumina from electroslagremelting of Ti-bearing blast furnace slag has been investigated by Bayer process, XRD methods. The effects of NaOH concentration , ratio of liquid to solid, leaching time and temperature, particle size, precipitating time and temperature, calcining temperature and time were investigated. With leaching, filtering, precipitating and calcining, alumina recovery of 75.56 pct was obtained under the conditions of NaOH concentration of 260 g/l, ratio of liquid to solid of 5:1, particle size of 85 pct passing 0.074 mm, leaching at 373 K (100°C) for 160 minutes , precipitating at 313 K (40°C) for 35 minutes and Calcining at 1473 K (1200°C) for 3 hours. KeywordsAlumina; Blast furnace slag; Bayer process; Electroslag-remelting;Recovery

Through the novel method in preparation of cathode, dehydration of molten salt etc, high purity of titanium (Ti) has been prepared by the electrochemical reduction of titanium dioxide (TiO2) .An investigation into the kinetics of the electrochemical reduction of TiO2 in molten calcium chloride (CaCl2) has been performed in according to electrochemical experiment. Partially reduced samples were prepared by terminating the reduction process after different reaction times and characterized by means of X-ray diffraction (XRD) analysis and chemical analysis.After analyzing, it is shown that the subsidiary reactions are the main reasons to affect the efficiency of current. Finally the methods to improve the efficiency of current have been provided.