Initial Nickel Concentration Research Articles

Removal of nickel(II) ions by histidine modified chitosan beads

In order to increase the nickel adsorption capacity of raw chitosan beads (CB), they were chemically modified with histidine (HIS–ECH–CB) by using crosslinking agent, epichlorohydrine (ECH). The nature and morphology of the sorbent were characterized using FTIR, TGA and SEM analysis. For optimization of adsorption conditions, sorption experiments were performed by varying contact time, pH, temperature and initial nickel concentration. Based on the adsorption experiment, the HIS–ECH–CB showed the significant adsorption capacity of 55.6mg/g under the optimal adsorption condition. Nickel adsorption isotherms data were fitted to Freundlich isotherm. Thermodynamic parameters namely ΔG°, ΔH° and ΔS° of the Ni(II) adsorption process were calculated. The negative values of Gibbs free energy of adsorption (ΔG°) indicated the spontaneity of the adsorption of Ni(II) ions on the histidine modified chitosan. Desorption of Ni(II) ions from HIS–ECH–CB could be done rapidly by using 0.1M HCl, HNO3 and EDTA solutions and the beads could be used again to adsorb Ni(II) ions.

The efficiency of Jordanian natural zeolite for heavy metals removal

The capability of Jordanian natural zeolite to remove nickel from aqueous solutions was experimentally investigated using a packed bed column. The zeolite samples were obtained from Jabal AL Aritayn in the northeast of Jordan. The effects of the initial concentration of nickel (C0), the packed bed length (L) and the zeolite grain size (Dp) on the adsorption process were considered. The finding indicated that these parameters named had a significant effect on the removal of nickel by the Jordanian zeolite. The characteristic breakthrough curves of the adsorption process were measured. The Klinkenberg model was adopted to explain the kinetic behavior of the adsorption phenomena, and we attempted to fit the packed bed experimental data to the breakthrough curve. The effective diffusivity was estimated and used to predict breakthrough curves under other adsorption conditions.

Micellar enhanced ultrafiltration (MEUF) and activated carbon fibre (ACF) hybrid processes for nickel removal from an aqueous solution

In the present study, nickel removal from an aqueous solution using micellar enhanced ultrafiltration at various operating parameters such as initial permeate flux, retentate pressure, initial nickel concentration, pH, molecular weight cut-off and molar ratio of nickel to sodium dodecyl sulphate (SDS) was investigated. The SDS surfactant removal from an aqueous solution using activated carbon fibre (ACF) was also monitored. The removal efficiency of nickel from an aqueous solution increased with an increase in the retentate pressure, initial permeate flux, pH and molar ratio of nickel to SDS, while the specific and relative fluxes declined. Considering the nickel removal efficiency and the permeate flux, initial permeate flux of 1.05 m3/m2/day, nickel to SDS molar ratio of 1:10 and operating retentate pressure of 1.4 bar were found to be the optimum operating parameters within the experimental condition for 0.5mM or less initial nickel concentration. At the optimized experimental condition,the nickel removal efficiency was 98% and the corresponding permeate nickel concentration was less than 1 mg/L. Similarly, two ACF cartridge units in series have removed the SDS up to 85% and the adsorptive capacity of ACF for SDS was 170 mg/g. the Langmuir isotherm equation fitted better with the experimental results than the Freundlich isotherm equation.

Effect of nickel incorporation on microstructural and optical properties of electrodeposited diamond like carbon (DLC) thin films

A simple electrodeposition technique was used to synthesize diamond like carbon (DLC) and nickel incorporated diamond like carbon (Ni-DLC) thin films on ITO coated glass substrates. Initial concentration of nickel in the electrolyte was kept fixed at 4.76×10−4M for all depositions of Ni-DLC films. Growth process of the films was studied by synthesizing films with variation of deposition time. With nickel addition to DLC the band gap and the Urbach energy varied from 2.67eV to 2.48eV and 1.0803eV to 1.452eV, respectively as estimated from UV-vis-NIR spectrophotometry of DLC and Ni-DLC. Results indicated that the metal incorporation effectively increased the graphitization of DLC films. Microstructural studies by SEM and AFM revealed that the particles in the Ni-DLC films were evenly distributed and the packing density of particles increased with increased time of deposition. XRD pattern exhibited the presence of Ni crystallites in an amorphous carbon network along with the phases of diamond and graphite in the Ni-DLC film. The FTIR spectrum showed peaks accountable for both CH3 and CH2 bonding. It was also apparent that nickel incorporation significantly modulated the FTIR spectrum of DLC film, as several new peaks appeared only in the case of Ni-DLC film at ∼776cm−1, 745cm−1 and 668cm−1.

Evaluation of transgenic tobacco plants expressing a bacterial Co–Ni transporter for acquisition of cobalt

Phytoremediation is a viable strategy for management of toxic wastes in a large area/volume with low concentrations of toxic elemental pollutants. With increased industrial use of cobalt and its alloys, it has become a major metal contaminant in soils and water bodies surrounding these industries and mining sites with adverse effects on the biota. A bacterial Co–Ni permease was cloned from Rhodopseudomonas palustris and introduced into Nicotiana tabacum to explore its potential for phytoremediation and was found to be specific for cobalt and nickel. The transgenic plants accumulated more cobalt and nickel as compared to control, whereas no significant difference in accumulation of other divalent ions was observed. The transgenic plants were evaluated for cobalt content and showed increased acquisition of cobalt (up to 5 times) as compared to control. The plants were also assessed for accumulation of nickel and found to accumulate up to 2 times more nickel than control. At the same initial concentration of cobalt and nickel, transgenic plant preferentially accumulated cobalt as compared to nickel. The present study is perhaps the first attempt to develop transgenic plants expressing heterologous Co transporter with an improved capacity to uptake cobalt.

Practical assessment of electrocoagulation process in removing nickel metal from aqueous solutions using iron-rod electrodes

Abstract The aim of this study was to investigate the practical application of electrocoagulation (EC) process in removal of nickel from aqueous solutions by iron-rod electrodes. This experimental research was carried out as a pilot scale using forty bipolar iron-rod electrodes in a glass container with a 1.5 l capacity which was connected to an electrical source. The removal efficiency of nickel from synthetic solutions was measured with initial nickel concentrations of 5 and 500 mg l−1, at pH of 3, 7 and 10, reaction times of 20, 40, 60 and 80 min and electrical potentials of 20, 30 and 40 V. Results showed that by increasing pH, nickel removal effi ciency for each concentration has increased, as much as 99.9% and 99.8% for 500 and 5 mg l−1 concentrations respectively. The optimum removal effi ciencies at nickel concentrations of 500 and 5 mg l−1 were reached at 20 and 40 min of reaction time and 20 V of potential difference respectively. The final pH of treated solutions has also increased which was du...

Adsorption of Ni(II) on ion exchange resin: Kinetics, equilibrium and thermodynamic studies

This article describes the ion exchange of a heavy metal Ni(II) from aqueous solutions onto a Dowex HCR-S, cationic resin. Batch adsorption studies were conducted to evaluate the effect of various parameters such as pH, resin dose, stirring speed, temperature, contact time and initial Ni(II) concentration on the removal of Ni(II). Adsorption rate increased with the increase in initial nickel concentration, stirring speed and temperature. Equilibrium adsorption isotherms were measured for the single component system, and the experimental data were analyzed by using Langmuir, Freundlich, Elovich, Temkin, Khan, Sips, Toth, Koble-Corrigan and Radke-Prausnitz isotherm equations. The Sips equation appears to fit the equilibrium data. Different models were tested for their applicability. Adsorption kinetic data were modeled using the Lagergren pseudo-first-order, Ho’s pseudo-second-order and Elovich models. It was found that Ho’s pseudo-second-order model could be used for the prediction of the system’s kinetics. Thermodynamic activation parameters such as ΔG*, ΔS* and ΔH* of the adsorption of Ni(II) on Dowex HCR-S cationic resin were also calculated.

Adsorption of Nickel (II) Ions From Aqueous Solutions Using Alumina

The paper presents the results achieved during the process of nickel removal from aqueous solutions by adsorption on alumina (Aluminum oxide) in continuous conditions. The continuing experiments were conducted in a glass column with diameter of 16 mm and fixed bed of adsorbent with quantity ranging from 30 to 115 g, adsorbent grains size from 1.0 to 2.0 mm, and retention time of 0.5 to 12 minutes. The quantity of nickel in the aqueous solutions was changed within the range of 0.045 up to 0.12 mg/l Ni. The analysis of the obtained experimental data defined the mutual affection of the retention time, the initial nickel concentration in the water, and the adsorbent quantity, i.e. the content of the adsorbent in the treated solution to the adsorbent capacity.According to the achieved results, logarithmic mathematical model showed best correlation between experimental and calculated values, also maximum nickel ions adsorption uptake onto the alumina were determined as 400 mg/g.

Identification and characterization of Leucobacter sp. N-4 for Ni (II) biosorption by response surface methodology

In the present study, batch experiments were carried out to characterize and optimize the removal process of Ni (II) by a nickel tolerant strain Leucobacter sp. N-4, which was isolated from the soil samples. The effects of operating parameters with respect to initial solution pH (3.0–6.5), initial nickel concentration (50–100 mg/L) and biomass dosage (1–10 g/L) on Ni (II) biosorption were investigated by response surface methodology (RSM). The maximal Ni (II) removal efficiency (nearly 99%) was achieved under the following conditions: pH 4.75, biomass dosage 5.38 g/L and initial Ni (II) concentration 53.6 mg/L. The adsorption-equilibrium data fitted well with both Langmuir and Freundlich isotherms. The monolayer adsorption capacity of biomass obtained from Langmuir isotherm was about 19.6 mg/g. Infrared spectrometer (IR) results showed that chemical functional groups (e.g. –NH 2, –OH and COO–M) of the biomass should be the active binding sites for Ni (II) biosorption from aqueous solutions.

Adsorption of Nickel Ions from Aqueous Solutions by Nano Alumina: Kinetic, Mass Transfer, and Equilibrium Studies

The presence of nickel in aquatic systems due to discharge of industrial effluents is of concern because of its toxic and nonbiodegradable nature. Its removal from water and wastewater is mandatory. Though activated carbon has been effective in removing metallic species including nickel from water and effluents, its high cost limits its large scale application to developing nations. The present paper addresses the removal of nickel from aqueous solutions by alumina nano particles. The adsorbent, nano alumina powder, was synthesized in the laboratory and was characterized by X-ray diffractometry (XRD), Fourier transformation infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The BET surface area and porosity of nanosized alumina powder were found to be 78.79 m2 g−1 and 0.51, respectively. The initial concentration of nickel, agitation speed, and contact time were found to affect the removal of nickel from aqueous solutions. Kinetic studies were performed and pseudofirst order, second...

Adsorption of Nickel(II) Ion from Aqueous Solution Using Rice Hull Ash

Rice hull was calcined to rice hull ash (RHA) at 500°C under 20 mL air s−1 for 50 min. The RHA thus prepared has been found to adsorb nickel(II) ion from aqueous solution efficiently. Experimental results indicated that the rate of adsorption of nickel ion and the adsorption of nickel ion at equilibrium were increased upon decreasing RHA dosage. They were also increased with increasing initial nickel concentration or adsorption temperature. On the other hand, they were found to remain unchanged when the initial pH was increased from 2.3 to 5.6, or the stroke speed was changed in the range of 30–180 stoke min−1. The kinetic data obtained obeyed the pseudo-second-order rate equation. An empirical equation correlating the relationship between the adsorption of nickel ion and the adsorption time was also determined.

Effect of peanut hull ash dosage on the degree of influence of operation variables on the adsorption of nickel ion from aqueous solution using peanut hull ash

This paper examines the role of peanut hull ash dosage (PHA dosage) in studies on the degree of influence of operation variables such as initial nickel concentration, initial pH, stroke speed and adsorption temperature on the adsorption of nickel ion from aqueous solution using PHA. The experimental results indicated the degree of the effects of these variables were very significant or pronounced for low PHA dosage; while those were strong or null for high PHA dosage. It is suspected that the effects of those operation variables are concealed by the effect of the PHA dosage.

Adsorption behavior of nickel(II) onto cashew nut shell: Equilibrium, thermodynamics, kinetics, mechanism and process design

The adsorption behavior of nickel(II) from aqueous solution onto agricultural waste such as cashew nut shell (CNS) was investigated as a function of parameters such as solution pH, CNS dose, contact time, initial nickel(II) concentration and temperature. The Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models were applied to describe the equilibrium isotherms using nonlinear regression analysis. The equilibrium data fits well for the both Langmuir and Freundlich adsorption isotherms. The Langmuir monolayer adsorption capacity of CNS was found to be 18.868 mg/g. Thermodynamic parameters such as Δ G°, Δ H° and Δ S° have also been evaluated and it has been found that the sorption process was feasible, spontaneous and exothermic in nature. Pseudo-first-order, pseudo-second-order and Elovich kinetic models were used to describe the kinetic data and the rate constants were evaluated. The result of the kinetic study shows that the adsorption of nickel(II) could be described by the pseudo-second-order equation, suggesting that the adsorption process is presumably chemisorption. The adsorption process was found to be controlled by both surface and pore diffusion, with surface diffusion at the earlier stages followed by pore diffusion at the later stages. Analysis of adsorption data using a Boyd kinetic plot confirmed that external mass transfer is the rate determining step in the sorption process. A single-stage batch adsorber was designed for different CNS dose/effluent volume ratios using the Freundlich equation.

Kinetics of nickel biosorption by acid‐washed barley straw

AbstractThis work reported the rate of nickel biosorption using acid‐washed barley straw (AWBS) at different initial nickel concentration, AWBS particle size, solution pH, and temperature. The biosorption process was rapid and the equilibrium was reached in about 100 min with initial nickel concentrations from 250 to 1000 mg/L. AWBS with particle size of <0.425 mm exhibited a greater adsorption rate and reached equilibrium faster than particle sizes of 0.425–1.18 mm. An increase in pH from 3.0 ± 0.1 to 7.0 ± 0.1 increased the rate of adsorption and resulted in a higher equilibrium nickel uptake. Nickel adsorption was more favourable at 23 ± 1°C compared to 5 ± 1°C and 40 ± 1°C. The external mass transfer model was able to fit the dynamic nickel biosorption data and provided acceptable overall volumetric mass transfer coefficients.

Preparation of agriculture residue based adsorbents for heavy metal removal

Guava seeds, a byproduct produced during guava juice processing, are currently of no economic value. In the present work two different types of adsorbents have been prepared from raw guava seeds, namely chemically activated guava seed carbon (AGSC) using zinc chloride and chemically modified guava seeds (MGS) through graft co-polymerization reaction. The adsorption capacity of both adsorbents towards Ni(II) has been investigated. It has been found that the equilibrium adsorption capacity is a function of initial pH, contact time, initial nickel(II) concentration, and adsorbent dosage. The optimum pH for both adsorbents was found to be 6. Both Langmuir and Freundlich models best describe the equilibrium experimental data. The maximum adsorption capacities for AGSC and MGS are 18.05 and 32.05 mg/g respectively. The kinetic experimental data were fitted well by the second-order model. The natures of the main functional groups which may be present on raw guava seeds and MGS have been investigated by infrared (IR) studies.

Base Treated Cogon Grass (Imperata cylindrica) as an Adsorbent for the Removal of Ni(II): Kinetic, Isothermal and Fixed‐bed Column Studies

AbstractThe adsorption of Ni(II) from aqueous solutions using base treated cogon grass or Imperata cylindrica (NHIC) was performed under batch and column modes. Batch experiments were conducted to determine the factors affecting adsorption such as pH, adsorbent dosage, initial nickel concentration, contact time and temperature. The fixed‐bed column experiment was performed to determine the practical applicability of NHIC and to obtain the breakthrough curve. Adsorption was fast as equilibrium was achieved within 60 min, and was best described by the pseudo second order model. According to the Langmuir model, a maximum adsorption capacity of 6.96 mg/g was observed at pH 5 and at a temperature of 313 K. Thermodynamic parameters such as ΔG0, ΔH0 and ΔS0 were calculated, and indicated that adsorption was a spontaneous and endothermic process. The mechanistic pathway of Ni(II) uptake was examined by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X‐ray (EDX) spectroscopy. The Thomas and Yoon‐Nelson models were used to analyze the fixed‐bed column data.

Biossorção de níquel e cromo de um efluente de galvanoplastia utilizando alga marinha pré-tratada em coluna

This work investigated the biosorption of chromium (III) and nickel (II) present in the effluent of a galvanoplasty plant using the pre-treated biomass of Sargassum filipendula seaweed. The column operation conditions were 8 g of biosorbent mass, 3.85 pH for the feed effluent, 30oC temperature, 6 mL min. -1 flow rate, 7.12 meq L -1 initial chromium concentration and 3.66 meq L -1 initial nickel concentration. A mathematical model was used to represent the dynamics of biosorption of the metals in a fixed-bed column. The Langmuir multicomponent isotherm model (q m = 2.78 meq g -1 , b Cr = 0.85 L meq -1 , b Ni = 0.08 L meq -1 ) was used to represent the equilibrium data of the column and to simulate the biosorption dynamics of the ions. The simulation results showed that the mathematical model described satisfactory the complex binary biosorption of chromium and nickel in the effluent.

Sorption of Ni(II) ions from aqueous solution by Lewatit cation-exchange resin

Ion-exchange is an alternative process for uptake of heavy metals from aqueous solutions. In the present study, the sorption of nickel(II) ions from aqueous solution was investigated by using Lewatit MonoPlus SP 112 (strongly acidic, macroporous cation-exchange resin) in a batch adsorption system as a function of pH (2.0–8.0), initial nickel concentration (50–200 mg/L), resin dosage (0.5–2.0 g/L), contact time (0.5–3 h), and temperatures (298–318 K). The data were analyzed on the basis of Lagergren pseudo-first order, pseudo-second order (Types 1–5), Elovich and external, Weber–Morris intraparticle, pore–surface mass diffusion models. The experimental data showed that the maximum pH for efficient sorption of nickel(II) was 6.0. At the optimal conditions, nickel(II) ions sorption on the resin was decreased when the initial metal concentration increased. The results indicated that the resin dosage strongly affected the amount of nickel(II) ions removed from aqueous solution. The adsorption process was very fast due to 80% of nickel(II) sorption was occurred within 30 min and equilibrium was reached at about 90 min. Freundlich and Langmuir adsorption isotherm models were used for sorption equilibrium data and the maximum adsorption capacity (171 mg/g) of Lewatit MonoPlus SP 112 was obtained from Langmuir isotherm. The thermodynamic parameters (Δ G°, free energy change; Δ S°, enthalpy change; and Δ H°, entropy change) for sorption of nickel(II) ions were evaluated. The rise in temperature caused a partly increase in the value of the equilibrium constant ( K c) for the sorption of nickel(II) ions. Moreover, column flow adsorption study was also studied. Breakthrough curves were obtained from column flow studies by using both synthetic solution and rinsing bath water of filter industry. The column regeneration was carried out for two sorption–desorption cycles. The eluant used for regeneration of the cation-exchange resin was 7% (w/w) HCl. The experimental results demonstrated that Lewatit MonoPlus SP 112 cation-exchange resin could be used effectively for the removal of nickel(II) ions from aqueous medium.

The effect of nickel(II) ions on the growth and bioaccumulation properties ofEscherichia coli

The influence of nickel(II) ions concentration on the growth and nickel(II) bioaccumulation properties of Escherichia coli (cultivated in the LB medium) was studied. When the investigated initial concentration of nickel(II) was in the range of 20–300 mg L−1, it was found that the growth of E. coli was delayed obviously with the increasing nickel(II) ion concentration, while the accumulation capacity increased until the maximum was obtained. FTIR spectrum showed that the peak near 3300 cm−1 shifted remarkably, and simultaneously, the peaks at 1660 cm−1 strengthened according to the nickel(II) concentration. As shown by the X-ray photoelectron spectroscopy analysis, the nitrogen, sulphur, and phosphorus contents of the cultivated cell were reduced, while the content of oxygen was increased. The biologic characteristics of the microorganism did not change as shown in the transmission electron microscope images. © 2008 American Institute of Chemical Engineers Environ Prog, 2009

Alumina Nanoparticles for the Removal of Ni(II) from Aqueous Solutions

Alumina nanoparticles were developed by the sol−gel method and were used for the removal of Ni(II) ions from aqueous solutions. The nanoparticles were characterized by TEM and XRD. Nanoparticles of alumina were then used for removal of Ni(II) ions from aqueous solutions of nickel. The nanosize of the adsorbent was confirmed by TEM and XRD. Removal (%) was found to be dependent on the initial concentration of nickel, and maximum removal was found to be 96.6% at 25 mg/L Ni(II). The removal increased from 99 to 99.6% by decreasing the initial concentration from 75 to 25 mg/L. Equilibrium time was found to be 120 min. As expected, higher removal was obtained at higher adsorbent dose. The removal was governed by first-order kinetics, and the value of the rate constant of adsorption was found to be 1.83 × 10−2 min−1 at 25 mg/L and 25 °C. The removal was found to be pH dependent, and maximum removal was found to be at pH 8.0. The adsorption process was endothermic in nature. The experimental data fit well the La...