Initial Nickel Ion Concentration Research Articles

Adsorption of Ni2+ by functionalized hydroxyapatite-chitosan composite

Abstract Chitosan and hydroxyapatite are commonly used materials for adsorption. In this work, chitosan was modified by polyethylene glycol and maleic anhydride. Subsequently, a hydroxyapatite-chitosan composite was synthesised by precipitation. The composite was characterised and analysed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Adsorption experiments were used to investigate the effects of external factors such as different pH values, adsorbent dosage, adsorption time and initial nickel ion concentration on the adsorption capacity of Ni2+ and to discuss the mechanism of Ni2+ removal by composites. The results show that the hydroxyapatite-chitosan composite has significant adsorption of Ni2+. The adsorption capacity of the hydroxyapatite-chitosan composite for Ni2+ reaches 63.8 mg g−1. The adsorption process is consistent with the pseudo-second-order kinetic model and the Langmuir isothermal model.

Recovery of nickel from electroless nickel plating wastewater based on the synergy of electrocatalytic oxidation and electrodeposition technology.

Nickel exists primarily as a stable complex in electroless nickel plating wastewater, and the Ni recovery from it cannot be achieved solely through electrodeposition. As the electrocatalytic oxidation has excellent oxidation potential to break down the complex, an efficient and stable electrochemical system using the synergy of electrocatalytic oxidation and electrochemical deposition technology was developed for the recovery of nickel from electroless nickel plating wastewater. In the present study, the effects of initial pH, current density, and initial nickel ion concentration on the treatment performance of the electrochemical system was investigated. The highest Ni recovery (94.84%) and total organic carbon removal (63.94%) were achieved at a current density of 83.3mA/cm2 , initial pH of 3.0, and initial Ni concentration of 0.01 M. At the same time, the recovered nickel product was confirmed by scanning electron microscopy, energy dispersive X-ray, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Furthermore, the electrochemical system displayed good stability and economic benefits, thereby suggesting its excellent application potential for the treatment of electroless nickel plating wastewater. PRACTITIONER POINTS: An efficient and stable electrochemical system was developed for the recovery of nickel from electroless nickel plating wastewater. In an acidic medium, the nickel recovery rate and TOC removal ratio were 94.84% and 63.94%, respectively. The system displayed good stability, thereby suggesting its excellent application potential for the treatment of nickel plating wastewater.

The Influence of Salt Anions on Heavy Metal Ion Adsorption on the Example of Nickel.

The biodegradable polysaccharide chitosan possesses protonated and natural amino groups at medium pH values and has therefore been used as an adsorbing material for nickel salts in water treatment. Nickel is a problematic heavy metal ion which can cause various diseases and disorders in living organisms. Here, we show the influence of oxyanions (e.g., nitrate and sulfate) to the adsorption of nickel ions. Hence, simultaneously we are addressing the increasing global problem of nitrate and sulfate ion pollution in groundwater and surface water. A series of adsorption experiments was carried out in order to determine (i) the adsorption equilibrium, (ii) the adsorption capacity in dependence on the initial nickel ion concentration, and (iii) the influence of the anion presented in solution for the adsorption capacity. Surface morphology of chitosan flakes before and after the adsorption process has been studied with SEM-EDX analysis. The chitosan flakes exhibited promising adsorption capacities of 81.9 mg·g−1 and 21.2 mg·g−1 for nickel (sulfate) and nickel (nitrate), respectively. The calculated values of Gibbs free energy change ΔG0 confirm the higher adsorption of nickel ions in presence of sulfate ions. Hence, higher anion valence leads to a higher adsorption capacity.

Adsorption kinetics and isotherms for the removal of nickel ions from aqueous solutions by an ion-exchange resin: application of two and three parameter isotherm models

The capacity of a strong cation-exchange resin for removal of nickel from aqueous solutions was investigated under different conditions such as contact time, initial nickel ion concentration, stirring speeds, solution pH, and resin dose. The equilibrium isotherm data were analyzed using Langmuir, Freundlich, Temkin, Elovich, Fowler–Guggenheim, Kiselev, Hill–de Boer, Jovanovic, Hill, and Koble–Corrigan isotherms. Correlation coefficients indicated the following order to fit isotherms: Langmuir > Koble–Corrigan > Freundlich > Hill > Jovanovic > Temkin > Hill–de Boer > Fowler–Guggenheim > Kiselev > Elovich. On the basis of the lowest values of the four error functions studied, Hill model provided the best correlation for the experimental data. The kinetic data were analyzed using pseudo-first-order, pseudo-second-order, and Elovich model. Intra-particle diffusion model and the liquid film diffusion model were used to investigate the adsorption mechanism. Kinetic studies showed that the adsorption of Ni2+ ions onto ion-exchange resin followed Elovich kinetic model, and indicates that the intra-particle diffusion controls the rate of adsorption. Furthermore, separation factors and distribution coefficients of nickel were calculated.

Natural zeolite for nickel ions removal from aqueous solutions: optimization and modeling using response surface methodology based on central composite design

Natural zeolite was tested as a low-cost adsorbent for Ni(II) removal from aqueous solutions. In order to reduce the total number of experiments necessary for achieving the best conditions of the batch sorption procedure, response surface methodology based on central composite design was carried out for the natural zeolite. Four independent variables, viz. initial nickel ion concentration (10–200 mg/L), adsorbent dose (0.1–0.7 g/L), contact time (5–120 min), and initial pH of solution (2–8) were transformed to coded values and the quadratic model was built to predict the responses. Very high regression coefficients between the variables and the response indicate excellent evaluation of experimental data using a second-order polynomial regression model. Three-dimensional plots demonstrate relationships between the nickel ion uptake with the paired factors (as the fourth factor was kept at its optimal level), which illustrate the behavior of the sorption system in a batch process. The model showed that nickel uptake in aqueous solution was affected by all four factors studied. An optimum nickel uptake was achieved at an initial nickel ion concentration of 10–15 mg/L, clinoptilolite dosage of 0.37–0.43 g/L, a contact time of 56–68 min, and a pH of 4.8–6. On the basis of experimental results and model parameters, it can be inferred that the adsorbent, which exhibits a relatively high adsorption capacity, can be utilized for the removal of nickel from aqueous solution.

Adsorptive removal of nickel from aqueous solutions by activated carbons from doum seed (Hyphaenethebaica) coat

The present study investigates the possibility of using low cost agriculture waste as doum-palm seed coat for the removal of nickel ions from aqueous solutions. Two activated carbons had been prepared from raw doum-palm seed coat (DACI and DACII); as well, the raw material was used as an adsorbent (RD). Batch adsorption experiments were performed as a function of pH of solution, initial nickel ions concentration, dose of adsorbent and contact time. Adsorption data were modeled using Langmuir, Freundlich, Temkin and D–R Models. Different error analysis conforms that the isotherm data followed Freundlich models for all adsorbents. Adsorption kinetic data were tested using pseudo-first order, pseudo-second order and Elovich model. Adsorption mechanism was investigated using the intra-particle diffusion model. Diffusion coefficients were calculated using the film and intraparticle diffusion models. Kinetic studies showed that the adsorption of Ni2+ ions onto RD, DACI and DACII followed pseudo-second order kinetic model, and indicates that the intra-particle diffusion controls the rate of adsorption but it is not the rate limiting step.

Comparative Studies of Isotherm and Kinetics on the Adsorption of Cr (VI) and Ni (II) from Aqueous Solutions by Powder of Mosambi Fruit Peelings

This study focuses on the use of powder of Mosambi fruit peelings (PMFP) as an inexpensive and efficient adsorbent to remove Cr(VI) and Ni (II) from aqueous solutions. The influence of physico-chemical key parameters such as the initial metal ion concentration, pH, agitation time, particle size and adsorbent dosage has been considered in batch tests. Sorbent ability to adsorb Cr(VI) and Ni (II) ions were examined and the mechanism involved in the process was investigated. The optimum results were determined at an initial chromium ion concentration was 10mgL, p=2, agitation time=60min, an adsorbent dose (150 mg/50ml) and the particle size (0.6mm) Langmuir constants [Q0=7.51(mg/g) and b=1.69(L/mg)] Freundlich constant (Kf=2.94 ), Lagergren rate constants (Kad (min)=5.75 x10-2) for [Cr(VI)] 10 mgL and initial nickel ion concentration of 50 (mg L), pH=4,agitation time – 90 min, an adsorbent dose (125mg/50ml) and the particle size (0.6mm). The % adsorption, Langmuir constants [Q0=29.41(mg/g) and b=0.4789(L/mg)], Freundlich constant Kf= 23.92(mg/g) and n=2.24 (L/mg), Lagergren rate constants [Kad (min) = 4.37 x 10] for [Ni (II)] 50 (mg L), were determined for the adsorption system as a function of sorbate concentration. The equilibrium data obtained were tested using Langmuir, Freundlich adsorption isotherm Research Article International Research Journal of Pure & Applied Chemistry, 4(1): 26-45, 2014 27 model and the kinetic data obtained were fitted to pseudo first order model. Heavy metal removal with the above adsorbent appears to be technically feasible, ecofriendly and has high efficacy.

Application of the BDST model for nickel removal from effluents by ion exchange

The effect of pH on the equilibrium ion exchange capacity of nickel using an imino diacetate ion exchange resin has been studied to determine the pH for optimum metal uptake. A series of fixed bed ion exchange studies have been carried out using the resin to remove nickel from water and the effect of a number of process variables, including initial nickel ion concentration, resin particle size and effluent solution flowrate, have been studied. The Bed Depth Service Time (BDST) model has been applied to the experimental date with only limited predictive success and subsequently a modified “BDST” model has been successfully applied to the data to model the system.

Removal of nickel ions by cementation on zinc from NiSO4 solution in presence of accelerator non-toxic organic compounds

This work deals with the removal of nickel ions by cementation on zinc from dilute nickel sulphate solution. The effect of different parameters such as, initial nickel ion concentration, temperature, rotation speed of a magnetic stirrer and concentrations of 1-aryl-3-(1-phenylpyrazolo [3,4-b]quinoxalin-3-yl)-2-propenone derivatives on the rate of nickel ion removal were investigated. The cementation reaction followed first‐order kinetics and diffusion controlling steps. The rate of cementation was found to increase in the presence of pyrazolo-quinoxaline derivatives. The value of activation energy and the increase in the rate of cementation with stirring support the fact that cementation of Ni2+ on Zn is diffusion controlled. The deposit morphology of nickel in the presence of chalcones was found to be dendritic. The dendrites create a local surface roughness which induces the formation of eddies. These eddies enhance the rate of nickel cementation. The experimental results were analysed by quantum chemical calculations.

Surface modification of Cameroonian magnetite rich clay with Eriochrome Black T. Application for adsorption of nickel in aqueous solution

In this study, the surface of Cameroonian magnetite rich clay was modified using Eriochrome Black T, EBT by the batch adsorption method. The EBT-modified magnetite rich clays were used for nickel ions adsorption from aqueous solution. The effect of various experimental factors; the pH of solution, the influence of concentration, the temperature, the contact time and the particle size of the sample were studied by using the batch technique. Adsorption process was better described by the pseudo-second-order kinetic and Tempkin isotherm model. The results showed that the EBT adsorption onto samples is affected by the pH of solution and the maximum EBT ion adsorption takes place between pH 2 and pH 3. The characterization of the surface modification was performed with FTIR and ZPC measurements. The FTIR shows that chemisorption took place at the surface of the bulk samples. The EBT-modified magnetite rich clay presented a binding capacity of nickel ions about 30% higher compared to the unmodified samples from an initial nickel ions concentration of 5.26mmol using 0.5g of sample.

Adsorption study on orange peel: Removal of Ni(II) ions from aqueous solution

Adsorption of Nickel(II) ions from aqueous solution onto a low cost adsorbent-orange peel was investigated to evaluate the effects of pH, initial nickel ion concentration and adsorbent dose on the removal of Ni(II) systematically. The optimal pH value for Ni(II) adsorption onto the orange peel was found to be 5.0. Greater percentage of metal ion was removed with decrease in the initial concentration of metal ion and increase in amount of adsorbent used. Adsorption data was modeled using the Langmuir and Freundlich adsorption. The adsorption kinetics was found to follow pseudo-second-order rate kinetic model, with a good correlation (r 2 > 0.99) and intra-particle diffusion as one of the rate determining steps. Thermodynamic parameters (ΔG°, ΔS° and ΔH°) for sorption system was determined at five different temperatures. Key words: Orange peel, heavy metal ion, adsorption, isotherms, kinetics.

Biosorption of Ni(II) from electroplating wastewater by modified (Eriobotrya japonica) loquat bark

Biosorption of nickel ions from aqueous solutions by modified loquat bark waste (MLB) has been investigated in a batch biosorption process. The biosorbent MLB was characterized by FTIR analysis. The extent of biosorption of Ni(II) ions was found to be dependent on solution pH, initial nickel ions concentration, biosorbent dose, contact time, and temperature. The experimental equilibrium biosorption data were analyzed by three widely used two-parameters Langmuir, Temkin and Freundlich isotherm models. Langmuir and Temkin isotherm models provided a better fit with the experimental data than Freundlich isotherm model by high correlation coefficients R2. The maximum adsorption capacity was 27.548mg/g of Ni(II) ions onto MLB. The thermodynamic analysis indicated that the biosorption behavior of nickel ions onto MLB biosorbent was an endothermic process, resulting in higher biosorption capacities at higher temperatures. The negative values of ΔG° (−5.84kJ/mol) and positive values of ΔH° (13.33kJ/mol) revealed that the biosorption process was spontaneous and endothermic. Kinetic studies showed that pseudo-second order described well the biosorption experimental data. The modified loquat bark (MLB) was successfully used for the biosorption of nickel ions from synthetic and industrial electroplating effluents.

Enhanced biosorption of nickel(II) ions by silica-gel-immobilized waste biomass: Biosorption characteristics in batch and dynamic flow mode

Batch and dynamic flow biosorption studies were carried out using the waste biomass entrapped in silica-gel matrix for the removal of nickel(II) ions from synthetic solutions and real wastewater. Batch biosorption conditions were examined with respect to initial pH, S/L ratio, contact time, and initial nickel ion concentration. Zeta potential measurements showed that immobilized biosorbent was negatively charged in the pH range of 3.0-8.0. The immobilized biomass was found to possess relatively high biosorption capacity (98.01 mg g(-1)), and biosorption equilibrium was established in a short time of operation (5 min). The equilibrium data were followed by Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. Scanning electron microscope analysis was used to screen the changes on the surface structure of the waste biomass after immobilization and nickel(II) biosorption. Sorbent-sorbate interactions were confirmed by Fourier transform infrared spectroscopy. The applicability of sorbent system was investigated in a continuous mode, and column studies were performed under different flow rate, column size, and biosorbent dosage. Also, the proposed sorbent system was successfully used to remove the nickel ions from industrial wastewater in dynamic flow treatment mode. The results showed that silica-immobilized waste biomass was a low-cost promising sorbent for sequester of nickel(II) ions from synthetic and real wastewater.

Preparation of ultrafine core-shell nickel spheres via self-sacrificial template

Self-sacrificial template, which is freshly precipitated Ni(OH) 2 colloid, is used to fabricate ultrafine core-shell nickel spheres. The size distribution, morphology, chemical and catalyzed properties of the synthesized spheres can be controlled by regulating the preparation conditions. The varying conditions are: initial nickel ion concentration, the pH value of the solution, the scouring agent and the anion in saline solution. With very little Ni 2+ concentration in the solution, the hollow spheres are formed. The higher the alkali content, the more the ultrafine colloidal cores.

Biosorption of nickel on blank alginate beads, free and immobilized algal cells

The potential use of blank alginate beads, free (non-immobilized) live and dead and immobilized dead algal cells for the removal of nickel ions from aqueous solutions was investigated. Immobilization enhanced the sorption of nickel and repetitive use of the sorbent could be achieved. Increasing initial pH or initial nickel ions concentration resulted in an increase in nickel uptake. The experimental results were fitted satisfactory to the Langmuir and Freundlich isotherm models. The results of the kinetic studies showed that the sorption of nickel ions on blank alginate beads, free live, dead and alginate immobilized dead algal cells followed pseudo-second order kinetics.

Nickel Removal from Aqueous Solutions Using Sheep Manure Wastes

This paper reports a study on the potential use of sheep manure waste (SMW) for the removal of nickel ions from aqueous solutions. The adsorption of nickel ions from aqueous solutions on SMW has been studied as functions of contact time, initial pH, amount of sorbent, sorbent particle size, initial concentration of nickel ions, salt, and chelating agents. The experimental results showed that the SMW has a high affinity for nickel binding, where 79 % removal of 100 ppm initial nickel ions concentration was obtained using 8.0 mg SMW/mL, at pH 6.5 in 4 minutes equilibrium time. The equilibrium adsorption data were analyzed using four different isotherms: the Langmuir, Freundlich, Redlich-Peterson, and Sips isotherm equations. The results of the kinetic studies showed that the adsorption of nickel ions on SMW is a pseudo-first order with respect to the nickel ions solution concentration.

Adsorption of Ni(II) Ions of the Surface of SiC Powder in the Formation of Dispersion Coatings

The adsorption of Ni(II) ions on SiC powder in NiSO4 solution has been measured as part of the codeposition of solid particles with a metal. The influences of SiC concentration in suspension, of the initial nickel ion concentration and pH of the bath, and of the sort, particle size and preliminary preparation of the SiC have been determined.Some facts indicating that both Ni(II) and H+ ions adsorption processes coexist on SiC and compete with each other have been established. Application of the Freundlich and Langmuir isotherms to the system studied has been tested and the effect of temperature on a change of adsorption determined.