Initial Nickel Research Articles

Optimizing binary biosorption of cobalt and nickel ions on brown algae using a central composite design

One of the most valuable approaches to eliminate heavy metal ions from aqueous solutions is biosorption. Cobalt and nickel can be removed from aqueous solutions simultaneously using sodium chloride-treated Cystoseria indica, which is a kind of brown algae. Three parameters, including pH, initial concentration of heavy metals, and adsorbent mass, were designated to run batch adsorption experiments. The central composite design was employed to show the simultaneous change of all factors according to a pre-specified experimental matrix that creates a response model in which the interactions between the calculated responses and each variable as well as interaction influences, are revealed. R2 values for the computed model were 0.96 and 0.95 for the response surface 1 (cobalt) and 2 (nickel), respectively. Central composite design calculated the optimum adsorption process as pH, 5.9; biomass dosage, 0.06 g; initial nickel concentration, 91.94 mg/l; and initial concentration of cobalt 89.36 mg/l. The kinetic and isotherm models were engaged to evaluate the equilibrium data at the optimum condition. The biosorption of both heavy metal ions obeyed the intra-particle diffusion kinetic model best, with the equilibrium adsorption time at 80 min. The extended Freundlich isotherm model is better fitted for the equilibrium biosorption data of nickel and cobalt ions. The maximum biosorption of nickel and cobalt ions simultaneously at optimized condition was 69.99 and 75.21 mg/g, respectively.

Adsorption extraction of nickel (II) from industrial aqueous solutions

A scheme for the primary unit of a technological means for the adsorption extraction of nickel from industrial solutions resulting from the processing of oxidised nickel ores is presented. The solutions comprise an aqueous extract of complex compounds of transition metals from an ore having an initial nickel content of 1-2 %. The traditional stepwise treatment of the solutions is oriented towards sequential precipitation of metals by ammonia water in the form of hydroxides, involving their decantation and filtration, etc., which significantly complicates the process of obtaining the target metal. The adsorption process significantly increases the economic efficiency of the extraction process for this valuable metal. In terms of their properties, carbon sorbents are chemically resistant, able to endure the harsh conditions of high temperature exposure and treatments based on strongly acidic and strongly alkaline solutions. Moreover, such sorbents have a developed porous structure, a significant specific surface area and high mechanical strength. The process of nickel extraction using carbon adsorbents from solutions in a weakly alkaline environment at elevated temperatures is described. The scheme of the nickel (II) ion extraction by adsorption unit is based on the use of a fluidised bed whose operational parameters are calculated directly by studying the sorption of nickel ions. The adsorption extraction of nickel (II) ions facilitates the complete selective separation and derivation of the metal following desorption of a saturated solution making the process suitable for direct electrolytic metal production.

Constraints on the Physical Properties of SNe Ia from Photometry

Abstract We present a photometric study of 17 SNe Ia based on multi-color (Johnson–Cousins–Bessell BVRI) data taken at Piszkéstető mountain station of Konkoly Observatory, Hungary between 2016 and 2018. We analyze the light curves (LCs) using the publicly available LC-fitter SNooPy2 to derive distance and reddening information. The bolometric LCs are fit with a radiation-diffusion Arnett model to get constraints on the physical parameters of the ejecta: the optical opacity, the ejected mass and the initial nickel mass in particular. We also study the pre-maximum, dereddened color evolution by comparing our data with standard delayed detonation and pulsational delayed detonation models, and show that the 56Ni masses of the models that fit the colors are consistent with those derived from the bolometric LC fitting. We find similar correlations between the ejecta parameters (e.g., ejecta mass, or 56Ni mass versus decline rate) as published recently by Scalzo et al. (2019).

EFFECT OF RAPID THERMAL TREATMENT ТЕMPERATURE ON ELECTROPHYSICAL PROPERTIES OF NICKEL FILMS ON SILICON

Present work is devoted to determination the regularity of change of specific resistance and Schottky barrier height of nickel films on n-type silicon (111) at their rapid thermal treatment in the temperatures range from 200 to 550 °C. Nickel films of about 60 nm thickness were deposited by magnetron sputtering onto the silicon substrates having a resistivity of 0.58 to 0.53 Ohms×cm. The rapid thermal treatment was carried out in the range of 200 to 550 °C under heat balance mode by irradiating the backside of the substrates with non-coherent light flux in nitrogen ambient for 7 seconds. The thickness of the nickel films was determined by scanning electron microscopy. The sheet resistance of the samples was measured by a four-probe method. The Schottky barrier height was determined from I-V plots. It is shown that at a temperatureы of rapid thermal treatment of Ni/n-Si (111) 200–250 °C nickel will be transformed to Ni2Si, increasing in thickness by 1.15–1.33 times, specific resistance increases to 26–30 μOhm×cm, and Schottky barrier height decreases from 0.66 to 0.6 V. At a rapid thermal treatment temperature of 300°C the initial nickel film thickness increases by 1.93 times, the resistivity and Schottky barrier height decrease to 26–30 μOhm×cm and 0.59 V respectively due to the conversion of the Ni2Si into NiSi and the fixation of the barrier height by surface states at the silicidesilicon interface. Rapid thermal treatment of 350–550 °C transforms the original nickel film into NiSi, increases its thickness by 2.26–2.67 times, reduces its resistivity to 15–18 μOhm×cm and increases the Schottky barrier height to 0.62–0.64 V. The minimum defects and better reproducibility of electrophysical properties are characterized by NiSi films formed by rapid thermal treatment of nickel films on n-type silicon at a temperature of 400–450 °C. The results obtained can be used in the technology of integrated electronics products containing rectifying contacts.

Preparation of nickel porous materials by sintering nickel oxalate and sodium chloride after blending and reduction

In this paper, sodium chloride(NaCl) was used as the separator agent and the pore-forming agent. Nickel porous materials were prepared by sintering nickel oxalate(NiC2O4) and NaCl after blending and reduction. The pore micro morphology, porosity, pore size, pore size distribution and permeability coefficient of nickel porous materials at different sintering temperatures were studied. The results show that NaCl as a separator can effectively prevent numerous direct contacts between the initial nickel particles and then reduce the sintering agglomeration during the process of blending. Thus, uniformly mixed fibrous nickel powders and NaCl powders are prepared. Nickel porous materials prepared by sintering nickel oxalate and NaCl after blending and reduction have a pore structure composed of lapped pores between the fibrous nickel particles and the prefabricated pores formed by the pore-forming agent. By changing the sintering temperature, the porosity and pore structure characteristics of the materials can be well controlled, and the nickel porous materials with good pore properties are obtained. When the sintering temperature increases from 450 °C to 650 °C, the open porosity is 71.7 % ∼ 79.5 %, the average pore size is from 0. 519 μm ∼ 1.043 μm, and the permeability is from 0.076×10−12 m2 ∼ 0.19×10−12 m2. The pore size distribution shows three peaks at low sintering temperatures. The distribution gradually turns into a double peak and eventually tends to a single peak as the sintering temperature increases.

Study of the effect of the size of the initial nickel powder on the structure formation of the mixture during mechanical activation of titanium and nickel

The structure and morphology of the mechanoactivated powder mixture has significant impact on the process of further synthesis. In this paper, the influence of the sizes of the initial powders on the formation of the structure of the mechanoactivated powder mixture during mechanical activation and the formation of layered agglomerates in the powder mixture of titanium and nickel is studied. The evolution of the formation of the size and density of layered agglomerates with the participation of both small and large nickel powder after different times of mechanical activation is studied. The study showed that the mechanical activation process leads to the formation of layered agglomerates and an increase in activity, which is associated with an increase in the contact surface of dissimilar particles, the number of defects. It is established that the use of initial nickel of different dispersion contributes to the formation of different structure of mechanoactivated powder mixture.

Research of the foil production for the SHS process

Self-propagating high-temperature synthesis, discovered by Soviet scientists A.G. Merzhanov, I.P. Borovinskaya and V.M. Shkiro is a process with significant scientific and technological potential. It is used in industries to produce goods that have properties that cannot be reproduced by other methods. Self-propagating high-temperature synthesis may be used to obtain products of different geometric parameters and functional properties. The paper presents the results of studies on the production of a foil from Ni–Al powders for the subsequent implementation of the self-propagating high-temperature synthesis. In preliminary experiments, the properties of the initial aluminum and nickel powders were determined. Based on the results of the experiments, an assumption was made about the possibility of their use for foil production. The foil can be used for local heating of third-party products. It was proposed to obtain foil in two ways. The first method involves the powders mixture rolling in specialized powder rolling mills. The second method provides preliminary pressing of workpieces and their subsequent rolling. The study showed the rationality of the second method application. The initiation of the self-propagating high-temperature synthesis process was next performed. The most rational way to initiate the combustion process has been proposed. The analysis of the compositions of the reaction products was made.

Hydrodeoxygenation of karanja oil using ordered mesoporous nickel-alumina composite catalysts

Abstract This study presents a systematic investigation of hydrodeoxygenation (HDO) of karanja oil over ordered mesoporous nickel-alumina composite catalysts. These catalysts were prepared by the evaporation-induced self-assembly method. The catalysts showed the ordered mesoporous structure up to 15 wt% nickel content in the catalyst. The mesoporous structure, however, became disorder beyond this nickel content. The catalysts were associated with catalytically active dispersed tetrahedral (or octahedral) coordinated nickel aluminate with strong interaction with alumina and a negligible amount of catalytically poor extra-framework nickel. The mesoporous nickel-alumina composite catalysts thus demonstrated superior catalytic activity compared to mesoporous alumina and γ-Al2O3 supported nickel catalysts. Wide ranges of linear paraffins (C14-C22) were formed in the reaction with C17 alkane as the main product. The conversion of oxygenates was enhanced with the rise in initial hydrogen pressure and nickel content in the catalyst without affecting product distribution much. The cracking of heavy hydrocarbons was, however, significant at elevated reaction temperatures, resulting in high selectivity to C17 alkane. For the optimum nickel loading of 20 wt%, the conversion of oxygenates was almost 100% with about 70 wt% C17 alkane and 15 wt% each lower and higher than C17 alkanes at 633 K and 2 h reaction time.

Eco-friendly and economical gold extraction by nickel catalyzed ammoniacal thiosulfate leaching-resin adsorption recovery

Nickel catalyzed ammoniacal thiosulfate leaching-resin adsorption recovery, an environmentally friendly and cost-effective process, was developed to extract gold from a gold concentrate calcine. The catalytic mechanism was presented based on thermodynamic analysis that NH3 catalyzed the anodic dissolution of gold, and Ni3O4 catalyzed the cathodic reduction of O2. The leaching result indicates that thiosulfate consumption reduced considerably under nickel-ammonia catalysis, whilst gold leaching percentage was comparable with that under conventional copper-ammonia catalysis. The kinetics study demonstrates that the reaction orders of initial nickel (II), ammonia and thiosulfate concentrations were separately 0.21, 0.37 and 0.28. The apparent activation energy calculation shows that the catalytic efficiencies of nickel-ammonia and copper-ammonia were close, and gold leaching with nickel-ammonia catalysis was possibly diffusion controlled that was supported by the XPS analysis result. For the gold recovery from its actual leach solution by ion-exchange resin, the resin and desorbent dosages were less, and loaded gold could be desorbed by a simple one-step desorption process because nickel did not co-adsorb with gold on resin surface. Besides, gold leaching percentage only declined 1.8% after the leach solution was recycled five times, and thiosulfate consumption decreased 5.8 kg/t-calcine.

The survey of application of the linear and nonlinear kinetic models for the adsorption of nickel(II) by modified multi-walled carbon nanotubes

Pollution due to the presence of nickel is of great importance because of its toxic nature and non-biodegradability. Nickel is one of the most common heavy metals used in the industry. The purpose of the study is to investigate the efficiency of modified multi-walled carbon nanotubes (MWCNTs) on the adsorptive removal of nickel (II) from its aqueous environment and also to survey the applicability of the linear and nonlinear adsorption kinetic models on the process. The effects of process parameters including pH (4, 5, 7, and 10), MWCNT dosage (2.5, 5, 10, and 12 mg/L), initial nickel (II) ion concentration (25, 50, 100, and 125 mg/L) and contact time (5, 10, 25, and 40 min) on the removal efficiency of nickel using MWCNTs were studied, and their optimum conditions were also determined. Maximum nickel removal efficiency of 82% was observed at the optimum conditions of pH 10, MWCNT dosage of 10mg/L, initial nickel concentration of 100 mg/L and contact time of 10 min. The experimental data fitted best into the linear Ho (I) kinetic models than the other linear models. The rate-determining step of the process was found to be chemisorption. The correlation coefficient R2 values obtained for the linear and nonlinear models revealed that the nonlinear Ho adsorption kinetic provided a better explanation of the adsorption kinetic data of nickel removal by MWCNTs.

Physicomechanical, dynamic mechanical, and morphological properties of Polyurethane/NCC/AgNP nanocomposites and their application in removal of heavy metals from wastewater

Silver nanoparticles (AgNPs) were rapidly synthesized using sugar beet leaf extract, and the formation of nanoparticles was observed within 3 h. AgNPs uniformly were reacted onto the surface of nanocrystal cellulose (NCC) via complexation leading to NCC/AgNPs, (NCC/Ag) nanohybrids with varying concentration of AgNPs (0, 1, 4, 8, and 10%) along with 2 wt% of NCC. Polyurethane (PU) and PU/NCC/AgNPs were synthesized via in situ polymerization by varying the concentration of AgNPs (0, 1, 4, 8, and 10%) along with 2 wt% of NCC. The results recorded from transmission electron microscopy and X‐ray diffraction support the biosynthesis and characterization of AgNPs. The effects of NCC/AgNP content on the physicomechanical properties involving density, tensile behavior, and surface hardness of the nanocomposites have been measured. The effects of the NCC/AgNP content on the viscoelastic properties of PU were investigated using dynamic mechanical analysis (DMA). From DMA analysis, it has been noted that the incorporation of NCC/AgNPs leads to a change in Tg. The PU and PU/NCC/AgNP nanocomposites were employed as an excellent adsorbent for the adsorption of nickel (II) and lead (II) ions. The results indicated that ion adsorption basically relies on adsorbing time, solution pH, initial nickel and lead concentration, and adsorbent dosage. POLYM. COMPOS., 40:4004–4012, 2019. © 2019 Society of Plastics Engineers

Thermally Assisted Adhesion Enhancement in High-Phosphorous Electroless Nickel Plating

High-phosphorus electroless nickel is a widely recognized protective plating for oilfield metallic parts subject to corrosion and wear. In the present investigation, thermally activated diffusion treatment was applied to enhance electroless nickel (10-13 wt.% P) plating adhesion on low-alloy steel (UNS G41400) and reduce the risks of spalling. High-phosphorus electroless nickel (10-13 wt.% P) was applied to a variety of UNS G41400 low-alloy steel test samples as per ASTM B733 that were subsequently heat-treated in air for four distinct temperatures, i.e., 510, 540, 570, and 600 °C for 2-10 h. Following post-plating diffusion heat treatments, the initial amorphous electroless nickel was replaced by Ni3P precipitates dispersed in a crystalline nickel-rich phase, with an average hardness improvement from 500 to 700 HK. An increased atomic interdiffusion (from 400 to 3.5 µm) was observed at plating–substrate interfaces, resulting in enhanced adhesion and reduced susceptibility toward spalling. This improvement in adhesion was measured repeatedly through post-bending crack analyses and subsequently validated by interface microindentation. Along with diffusion across plating–substrate interface, nickel oxide formation on surface by oxidation was observed to grow at quasi-parabolic rate with no detrimental impact on spalling. In all cases, plating adhesion was improved by heat treatments due to the diffusion-controlled formation of a seemingly ductile layer.

Supernova lightCURVE POPulation Synthesis II: Validation against supernovae with an observed progenitor

Abstract We use the results of a supernova light-curve population synthesis to predict the range of possible supernova light curves arising from a population of single-star progenitors that lead to type IIP supernovae. We calculate multiple models varying the initial mass, explosion energy, nickel mass and nickel mixing and then compare these to type IIP supernovae with detailed light curve data and pre-explosion imaging progenitor constraints. Where a good fit is obtained to observations, we are able to achieve initial progenitor and nickel mass estimates from the supernova lightcurve that are comparable in precision to those obtained from progenitor imaging. For 2 of the 11 IIP supernovae considered our fits are poor, indicating that more progenitor models should be included in our synthesis or that our assumptions, regarding factors such as stellar mass loss rates or the rapid final stages of stellar evolution, may need to be revisited in certain cases. Using the results of our analysis we are able to show that most of the type IIP supernovae have an explosion energy of the order of log(Eexp/ergs) = 50.52 ± 0.10 and that both the amount of nickel in the supernovae and the amount of mixing may have a dependence on initial progenitor mass.

Synthesized Nano particle derivation of poly (Styrene - co- Maleic Anhydride) and sour cherry Rock for removing nickel (II) ion from aqueous solutions.

In this study, Prunus Cerasus Rock (PCR) and Poly (Styrene - co- Maleic Anhydride) modified with Melamine-Oxalic acid (SMA-MO) were used to prepare a cheap adsorbent through chemical modification. The maximum removal was observed at pH = 6.0 and adsorbent dose 1.5 g/L for initial Nickel -ions concentration 30 mg/L. Study of temperature effect proved that the process is endothermic. Langmuir and Freundlich isotherm models were used for equilibrium adsorption data. Langmuir isotherm proved to be a better fit. Pseudo first order and pseudo second order kinetic models were applied to analyze the kinetic mechanism of adsorption.

The potential of nonliving Sargassum hemiphyllum as a biosorbent for nickel(II) removal—isotherm, kinetics, and thermodynamics analysis

The ability of non‐living Sargassum hemiphyllum to remove nickel(II) from aqueous solutions was investigated. The optimum adsorption condition was occurred at a pH range from 4 to 8, a biomass of 0.5 g L−1, and an initial nickel(II) concentration of 250 mg L−1 with a contact time of 20 min. The Langmuir, Freundlich, and Dubinin‐Radushkevich isotherm models were used to fit the adsorption isotherms. The fitting results were more in line with the Langmuir model (R2 = 0.9915), and the maximum adsorption capacity obtained by Langmuir model was 42.95 mg g−1 at 308 K, respectively. The biosorption kinetics were analyzed using the pseudo‐first‐order, pseudo‐second‐order and intraparticle diffusion, and it was determined that they followed pseudo‐second‐order kinetics (R2 = 0.9996) at 308 K. The enthalpy (ΔH°) and entropy (ΔS°) change of adsorption was 3.95 kJ mol−1 and 20.28 J mol−1 K−1, respectively, which indicated that the adsorption was spontaneous and endothermic. The biosorbents were also characterized by Fourier infrared spectroscopy (FT‐IR), Scanning electron microscopy and Energy disperse spectroscopy (SEM‐EDS), and X‐ray photoelectron spectroscopy (XPS). The characterization analysis demonstrated that the functional groups such as hydroxyl, carboxyl, amino, and methyl on the algal surface involved in the adsorption for nickel(II). Our results suggested that the nonliving S. hemiphyllum could be used as an effective biosorbent for the removal of nickel(II) from wastewater. © 2018 American Institute of Chemical Engineers Environ Prog, 38: S250–S259, 2019

Nano Zero-Valent Iron Supported on Activated Carbon: Effect of AC/nZVI Ratio on Removal of Nickel Ion from Water

The present study investigated the possible effect of contact time, initial nickel concentration, and adsorbent concentration on removing Ni (II) ion, which is toxic to living organisms, from the aqueous media using nano zero valent iron (nZVI) and nano zero valent iron coated powdered activated carbon. A large portion of the nickel removal was achieved in a contact time of five minutes. A removal efficiency of barely 24% was able to be achieved only using activated carbon, while the nickel removal was achieved by approximately 80% using 200 mg/L nZVI. On the other hand, the efficiency was observed to increase up to 99% even with the particle containing the lowest nZVI in the experimental studies using the AC-nZVI nanoparticles containing AC at a rate of 25%, 50% and 75%. Adsorption capacity was increased from 125 mg/g and 820 mg/g for activated carbon and nZVI, respectively to 1190 mg/g for 50% AC-nZVI. Based on our study results, the effect of nZVI is promoted when nZVI is synthesized together with activated carbon. The Freundlich model was also found the best to represent the isotherm modeling made for nZVI.

Spheroidization of Nickel Powder and Coating with Carbon Layer through Laser Heating.

We developed a simple and efficient process, laser heating of nickel powder in ethanol, to produce carbon-encapsulated nickel microspheres. Long-pulse-width laser heated nickel powder suspended in pure ethanol into liquid droplets. In turn, the latter droplets became sphere-like, pyrolyzed surrounding ethanol and dissolved the produced carbon atoms. Because of their lower solubility in solid nickel, excess carbon atoms were then expelled from the metal core after solidification, thus forming graphite-like shells on the laser-modified Ni spheres. Hence, after pyrolysis the transformation of carbon was found to follow the dissolution-precipitation mechanism. The produced carbon-encapsulated nickel microspheres exhibited higher oxidation resistance compared with the initial nickel powder, while keeping their magnetic properties essentially unchanged.

Nanometric nickel exsolution in the hexagonal perovskite Ba8Ta6NiO24: Survey of the structural, magnetic and catalytic features

Nickel nanoparticles that decorate the surface of a parent oxide are well known to be developed by some cubic-type perovskites from the exsolution of their intrinsic Ni2+ species in reducing conditions with subsequent catalytic properties. In this work, we show similar phenomenon in a hexagonal-type perovskite. The reducing treatment in ammonia of Ba8Ta6NiO24, a hexagonal perovskite-type oxide, leads to the exsolution of nickel nano-sized particles at the surface of the precursor leaving oxygen vacancies and partially depleted but rearranged Ni/Ta sites. Spectroscopic methods, X-ray diffraction, TEM and TGA were employed to investigate the Ni exsolution while TGA was used to investigate the thermal behavior and its reversibility. 50% of the initial nickel content transferred into Ni0 nanoparticles as determined from M(H) magnetization plots and TGA, in agreement with the concomitant creation of oxygen vacancies in the preserved Ni2+ coordination (50%). The cationic vacancies (Vc) involve face-sharing octahedral dimers in which Ni/Ta/Vc rearranged through the shared face window, but preserved a non-centrosymmetric cationic partition. Ni exsoluted oxides often show a catalytic activity; we present here an original example of a hexagonal perovskite with catalytic activity toward syngas production by dry reforming of methane with carbon dioxide.

Low-Temperature Catalytic CO2 Dry Reforming of Methane on Ni-Si/ZrO2 Catalyst

The activity of a ZrO2-supported nickel catalyst promoted by silica (Ni-Si/ZrO2) in CO2 dry reforming of methane was carried out at 400 and 450 °C. The catalysts were prepared by an impregnation method and characterized by H2-TPR, XRD, TEM, TG-MS, Raman, XPS, and in situ XPS and DRIFTS. It was discovered that Ni-Si/ZrO2 showed higher initial conversion of CH4 (0.50 s–1) and CO2 (0.44 s–1), and stability for low temperature (400 °C) DRM reaction in comparison to an SiO2-supported nickel catalyst promoted by zirconia (Ni-Zr/SiO2) (0.32 s–1 for both CO2 and CH4). The Ni-Si/ZrO2 catalyst featured the formation of active nickel particles with a small size of 6–9 nm and with slightly strong electronic donor ability, stabilization of the initial metal nickel state under the reaction conditions, and the formation of easily removed C1 coke. However, for the 450 °C DRM reaction, the coke that formed on the Ni-Si/ZrO2 catalyst was mainly C2 coke that was difficult to remove, because the CO2 preferred to combine with...

Nickel removal from electroplating wastewater using electrocoagulation

Electrocoagulation processes for reducing nickel concentration in electroplating wastewater had been carried out in laboratory scale experiments. The experiments were conducted in a 500 mL batch reactor with dual electrodes: aluminum as the anode and copper as the cathode with electroplating wastewater at pH 7 and initial nickel concentration of 10,55 ppm. Parameters of electrocoagulation process such as removal efficiency, specific energy and produced precipitate were determined and assessed under various DC voltages (5, 7.5 and 10 V) and various operation time (30, 60 and 90 min) as variable of experiment. The results show that the optimum condition of electrocoagulation process was obtained at 5 VDC and for 76.5 min.