Corrosion behaviour of an aluminized nickel coating in a carbon dioxide capture process using aqueous monoethanolamine

Carbon steel A106 with an aluminized Ni coating was tested in a 5 mol/l (M) monoethanolamine (MEA) with a carbon loading of 0.2 mol/mol MEA at 80 °C using polarization resistance, Tafel, and electrochemical impedance spectroscopy (EIS) techniques. Surface morphology and elemental line profile of the coating were examined before and after a 900 °C heat-treatment in atmosphere environment. X-ray diffraction (XRD) results showed that the coating surface constitutes transformed from Ni₂Al₃ to Al-rich NiAl after heat-treatment. The electrochemical results show that the heat-treated coating displays outstanding corrosion performance with the conditions tested.     

Crevice corrosion initiation and propagation on Alloy-22 under galvanically-coupled and galvanostatic conditions

The initiation and propagation of crevice corrosion on the Ni–Cr–Mo Alloy-22 has been studied in concentrated chloride solutions under galvanically-coupled and galvanostatic conditions. Under galvanically-coupled natural corrosion conditions crevice corrosion initiated but propagation was limited by repassivation. This was attributed to the slow kinetics of oxygen reduction on passive surfaces external to the crevice. Under galvanostatic conditions a potential more positive than 200 mV_Ag/AgCl and an applied current greater than 5 μA were required to stabilize propagation. A minimum critical current density to establish active sites within the crevice was estimated to be around 250 μA cm⁻².     

Role of initial microstructure on nickel-YSZ cathode degradation in solid oxide electrolysis cells

Electrical performance degradation relating to materials interactions at elevated temperatures is one of the primary technical limitations to the near term successful commercialization of solid oxide electrolysis cells (SOECs). Electrochemical performance and structural degradation of nickel-YSZ fuel electrodes (SOEC cathodes) were studied as functions of materials, preparation techniques, and operating conditions. Significant electrochemical degradation was observed in cells operated at 840 °C with and without voltage bias. Carbon deposition, Ni evaporation, and impurity poisoning were not observed to negatively affect performance. However, the high Ni content and large initial Ni particle size caused rapid Ni migration and agglomeration. The agglomeration reduced Ni electrical interconnectivity as well as contact area with the current collector.     

Determination of the Optimum NiS Fire Assay Parameters for Pt,Pd, and Rh in Automotive Exhaust Catalytic Converters

This work investigates the performance of the nickel sulfide fire assay (NiS-FA) for the pyrometallurgical analysis of platinum group elements (PGEs) from mixtures of automotive exhaust catalytic converters (e.g., gasoline, diesel, and diesel particular filter) by assessing the effects of various flux materials and reaction parameters on platinum, palladium, and rhodium recovery. Inductively coupled plasma mass spectrometry and atomic absorption spectroscopy (AAS) are used for the analysis of the NiS-FA beads. We found that the optimum recovery (at least 99.0%) was achieved with reaction of 11.5 g of flux (0.53 w/w ratio, sodium tetraborate:sodium carbonate), 1 g nickel, and 0.84 g sulfur (1.2 w/w ratio, Ni:S) per gram of sample for 90 min at 975°C. Reference standards (NIST SRM 2557) were used to compare efficiencies and identify the optimum conditions. The results are consistent with certified values and PGEs could be recovered within the 95% confidence level. The precision (<4.0% RSD) of all measurements, expressed as percentage relative standard deviation (SD), ranged up to 3.0%.     

Removal of nickel(II) from aqueous solutions using iminodiacetic acid functionalized polyglycidyl methacrylate grafted-carbon fibers☆

Iminodiacetic acid functionalized polyglycidyl methacrylate grafted-carbon fibers (PGMA-IDA/CFs) were prepared for Ni(II) removal from aqueous solutions. The effects of solution pH value, temperature and adsorption time were investigated. The maximum adsorption capacity of Ni(II) on PGMA-IDA/CFs is 0.923 mmol·L?1 · g?1 at pH 5.2 and 50 °C. Kinetic data indicate that the adsorption process matches the pseudo-second-order model and Elovich kinetic model. Thermodynamic data suggest that the adsorption process is endothermic spontaneous reaction.     

成型和表面处理工艺对316L不锈钢镍释放率的影响

采用人工汗液浸泡法及火焰原子吸收光谱仪测试了316L不锈钢（/%:0.023C,17.57Cr,11.23Ni,2.03Mo）11种成型和表面处理工艺条件下的镍释放率。试验结果表明,50%压下率冷轧、1050℃固溶,镜面抛光的316L不锈钢型材镍释放率只有0.02 μg/cm²/周,很好地满足了欧盟新标准EN1811:2011的要求。但是成型工艺（冷轧态,铸态）表面处理方式（粗糙度）、取样方式（纵、横向）都会直接影响材料的镍释放率,使其提高3~26倍。     

Nickel diffusion in polycrystalline CuInSe2 thin films with a <112> fiber texture

Nickel diffusion in CuInSe₂ thin films was studied in the temperature range 430-520 °C. Thin films of copper indium diselenide (CuInSe₂) were prepared by selenization of CuInSe₂-Cu-In multilayered structure on glass substrate. A thin film of Nickel was deposited and annealed at different temperatures. Surface morphologies of the Ni diffused and undiffused CuInSe2 films were investigated using scanning electron microscope. The alteration of Nickel concentration in the CuInSe₂ thin film was measured by Energy Dispersive X-Ray Fluorescence (EDXRF) technique. These measurements were fitted to a complementary error function solution and the diffusion coefficients at four different temperatures were evaluated. The diffusion coefficients of Ni in CuInSe₂ films were estimated from concentration profiles at temperatures 430-520 °C as D = 1.86 × 10^− 7(cm²s^− 1)exp[− 0.68(eV)/kT].     

Hydrogen production by auto-thermal reforming of ethanol over nickel catalyst supported on mesoporous yttria-stabilized zirconia

Mesoporous yttria-stabilized zirconia (YSZ-X) supports with different Y/Zr molar ratio (X) were prepared by a sol–gel method. 20 wt% Ni catalysts supported on YSZ-X (X = 0, 0.1, 0.2, and 0.3) were then prepared by an incipient wetness impregnation method for use in hydrogen production by auto-thermal reforming of ethanol. The effect of Y/Zr molar ratio (X) on the catalytic performance of Ni/YSZ-X (X = 0, 0.1, 0.2, and 0.3) catalysts was investigated. Hydrogen selectivity and by-product distributions over the catalysts were different depending on the Y/Zr molar ratio (X). Hydrogen selectivity over Ni/YSZ-X (X = 0, 0.1, 0.2, and 0.3) catalysts showed a volcano-shaped curve with respect to Y/Zr molar ratio (X). Among the catalysts tested, Ni/YSZ-0.1 showed the best catalytic performance and the lowest carbon deposition in hydrogen production by auto-thermal reforming of ethanol. High reducibility and excellent structural stability of Ni/YSZ-0.1 catalyst were responsible for its superior catalytic performance.     

Copper doped nickel aluminate: Synthesis,characterisation, optical and colour properties

Novel environment friendly inorganic nano green pigments, Ni_1-xCu_xAl₂O₄ (x=0, 0.02, 0.04, 0.06, 0.08, 0.1) were successfully synthesised by simple, cost effective sol-gel method using citric acid as a gelling agent. Synthesised nano pigments were characterised by powder XRD, FT-IR, UV-DRS, SEM-EDX and TEM. Distribution of elements such as Ni, Cu, Al and O for the pigment Ni_0.98Cu_0.02Al₂O₄ was authenticated by elemental mapping analysis. The colour parameters were studied using CIE-LAB parameters. It is evident from the DRS measurement that the band gap energy of NiAl₂O₄ (3.11 eV) has been massively diminished to 2.63 eV when x=0.02, unexpectedly changed the colour of the pigment from cyan to green. Whilst x=0.1 the pigment colour has turned into grey and the corresponding band gap condensed into 2.17 eV. Effect of mineralisers like NaF, CaF₂, NH₄H₂PO₄ and Li₂CO₃ on the colour of Ni_0.98Cu_0.02Al₂O₄ was investigated.     

Determination of Aluminum in Nickel-Based Superalloys by Using Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy （LIBS） was developed to detect aluminum in nickel-based superalloys （K417, GH4033, DZ125L, З ∏742y） using a non-intensified...