Adsorption Capacity For Ni2 Research Articles

Functionalised graphene oxide dual nanocomposites for treatment of hazardous environmental contaminants

During the past few decades, water contamination has raised a huge concern due to rapid industrialization, agricultural wastes, metal galvanizations, and leather industries as a result of the discharge of organic pollutants, dyes and heavy metals. The present study investigates the synthesis of copper oxide nanoparticles (CuO-NPs) and graphene oxide-copper oxide nanoparticles (GO/CuO-NPs) for heavy metal ions adsorption like Ni2+ and Cd2+ from wastewater. For this purpose, batch and continuous adsorption studies were performed. The chemical and physical characteristics were analyzed by FTIR, XRD, SEM, and AFM. AFM analysis confirmed the hexagonal structure and an average diameter of 79.91, 82.01 and 21.45 nm for GO/CuO-NP, CuOn, and CuOm, respectively. In batch scale, it is concluded that GO/CuO-NPs showed the best adsorption capacity for Ni2+ and Cd2+ than CuOn and CuOm at pH value of 8, adsorbent dose of 250 mg, initial concentration of 50 mg/L, a contact time of 15 min. GO/CuO-NP showed the maximum Ni2+ and Cd2+ removal of 99.16 and 98.84 % respectively at 15 min contact time. Similarly, the maximum Ni2+ and Cd2+ ions removal of about 99.37 and 99.18 % was observed with GO/CuO-NPs at an adsorbent dose of 250 mg and 50 mg/L dye concentration. The adsorbent isotherm and kinetic analysis revealed that the results were best fitted with Langmuir isotherms and the Pseudo-second order model, respectively. While in continuous adsorption analysis, GO/CuO-NPs showed the best adsorption capacity for Ni2+ and Cd2+ than CuOn and CuOm at an initial concentration of 50 to 75 mg/L, a flow rate of 4 mL/min, and a bed height of 1.5 to 2 cm. However, the present study provides valuable insight into novel nanocomposites' development to eliminate Ni2+ and Cd2+ from industrial wastewater.

Effective adsorption of cadmium and nickel ions in mono and bicomponent systems using eco-friendly adsorbents prepared from peanut shells

The work investigates the potential of peanut shells, an abundant agro-industrial waste, to serve as an adsorbent precursor for the effective and simple treatment of effluents loaded with cadmium and nickel ions. Among the adsorbents prepared, carbonized peanut shell (CCarb), due to its higher adsorption capacity, proved to be the most effective compared to carbonized and activated peanut shell (CATQ). The carbonization process led to structural changes, which resulted in an increase in surface area (around 6 times more in CATQ) and pore volume (around 3 times more in CATQ). Even so, the amount of H+ acid sites due to acid activation produced unfavorable effects for adsorption. Hydroxyl, carboxyl and carbonyl groups were identified on the adsorbent surface which presented favorable charges for metal adsorption. This improvement propels the carbonized variant to the forefront, demonstrating the highest adsorption capacity and reaching equilibrium in less than 90 and 60 min for cadmium and nickel ions, respectively. In both monocomponent and bicomponent systems concentrations greater than 40 ppm signify an increase in adsorption capacity for Ni2+. The experimental data best fit the Freundlich model, showing maximum adsorption capacities of 17.04 mg g−1 for cadmium and 31.28 mg g−1 for nickel. Despite the antagonistic effect observed in the bicomponent system, this study concludes by underlining the promise of activated carbon from peanut shells to harmonize technical and environmental concerns.

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.

Study on the equilibrium and kinetics of nickel adsorption on rice husk: the role of activation

Rice husk is an agricultural byproduct that is produced in huge quantities during the rice milling process. Following the trend of utilizing agricultural waste, rice husk is activated by many activators to synthesize heavy metal ion adsorbent materials. This work presents the results of the study on the adsorption of nickel ions (Ni2+) by activated rice husks. The husk was activated by three agents (NaOH, acetic acid, and H2O2), which removed 73.29 percent of the hemicellulose and 60.25 percent of the ligin (calculated by the Chesson-Datta method). The influence of time on the adsorption capacity of Ni2+ ions of activated rice husks was carried out with an initial concentration of Ni2+ ions of 160mg/L and a pH of 5.5. The concentration of adsorbent was 1,0 g.L-1. After 80 minutes of adsorption, the equilibrium adsorption capacity reached 33.33 mg.g-1. The maximum adsorption capacity calculated by the Langmuir adsorption model was 57.46 mg.g-1. Three kinetic models (Lagergren's apparent first-order kinetics, second-order apparent kinetics and Webber-Morris internal diffusion kinetics) were also studied and analyzed.

Removal of nickel and copper ions in strongly acidic conditions by in-situ formed amyloid fibrils

The research investigated a novel strategy that can synchronously remove Ni2+ and Cu2+ by synthesizing amyloid fibrils under harsh conditions. The adsorption capacity of Ni2+ and Cu2+ increased by 18.5% and 34.1% respectively in the in-situ scenario as compared to that Ni2+ and Cu2+ were introduced after amyloid fibrils preparation, meantime, it avoids the generation of acidic waste liquid in the process of preparing amyloid fibrils. The adsorption behaviors of Ni2+ and Cu2+ can be well described by the pseudo-second-order kinetic model and Langmuir isotherm. The functional groups of amide, hydroxyl, and carboxyl played determining roles in the adsorption process. Moreover, when the amyloid fibrils were prepared in the presence of Ni2+ and Cu2+, i.e., the in-situ adsorption scenario, metal ions tended to occupy the functional sites, inhibit protein aggregation, and affect long amyloid fibrils synthesis accordingly. Metal ion-binding site prediction server was used to predict the binding sites of metal ions towards the protein sequence within amyloid fibrils, and the metal ion was observed to preferentially bind to a particular residue such as glutamic acid, cysteine, and serine. The amyloid fibrils be potentially valuable for the removal of heavy metals in strongly acidic wastewater such as acidic mining drainage.

Characterization of ZSM-5 monolith as solid sorbent for Ni2+ removal

Solid wastes exhibit excellent prospects in the removal of heavy metals from contaminated water. However, raw solid waste materials usually show mediocre uptake efficiency, it is imperative to functionalize or transform them into new solid waste-based materials. The present work provides a novel technique by utilization of silica fume waste for Ni2+ removal from wastewater. The sorbent was prepared by in-suit conversion of amorphous silica fume based geopolymer into monolithic ZSM-5 via polycondensation and seed-induced hydrothermal treatment process. The adsorption behavior of Ni2+ in aqueous solution onto the as-synthesized monolithic ZSM-5 was investigated. The adsorption experiment data fitted well with the pseudo-second-order kinetic model and Langmuir isotherm model. Thermodynamic parameters including ΔH, ΔG and ΔS were calculated from the temperature-dependent sorption isotherms. All the results confirmed that the sorption of Ni2+ onto monolithic ZSM-5 was a spontaneously endothermic chemisorption process, demonstrating the removal of Ni2+ from wastewater using monolithic ZSM-5 was feasible. The adsorption capacity of Ni2+ onto monolithic ZSM-5 was 13.22 mg/g at 25 °C, which was a competitive result compared with similar adsorbents and commercial ZSM-5 powders.

Preparation and properties of ternary copolymer hydrogel materials

In order to improve the adsorption of heavy metal ions on acrylic hydrogels, P(AA-co-AM-co-S) hydrogels were synthesized from acrylic, acrylamide and styrene as raw materials. During the synthesis, potassium persulfate was used as the initiator, N, N’-methylenebisacrylamide was used as the crosslinking agent, and the degree of neutralization was 80%. The structure of the prepared hydrogel was determined by infrared spectroscopy. The adsorption properties of hydrogels on Ni2+ at different times and pH were determined. The results show that the adsorption capacity of Ni2+ ions on the hydrogel reaches the equilibrium adsorption capacity in about 2 hours and reaches 159 mg/g. The second-order kinetic model fits well. The optimal pH for the adsorption of Ni2+ ions by the hydrogel is 3.5 ~ 4.5 and the adsorption capacity is 160 mg/g. This study has important theoretical and practical significance for the development of high-efficiency, environmentally friendly, low-cost heavy metal ion hydrogels.

Adsorption of Lead and Nickel on to Expanded Graphite Decorated with Manganese Oxide Nanoparticles

In this study, expanded graphite (EG) was decorated with manganese oxide nanoparticles (MONPs) by the hydrothermal method, and the newly formed composite (MONPs-EG) was applied as adsorbent for the removal of heavy metals from aqueous solutions. The comparative and competitive adsorption of Pb2+ and Ni2+ (0.01–1.00 mM) on MONPs-EG was investigated. Data from isothermal adsorption of single and binary systems suggested that both Pb2+ and Ni2+ were well described by the Langmuir isotherm, and the maximum adsorption capacities at 298 K were calculated at 0.278 and 0.113 mmol/g for Pb2+ and Ni2+, respectively. In binary systems, a dramatic decrease in adsorption capacity of Ni2+ was observed, while the adsorption capacity of Pb2+ was almost stable, indicating the favorable adsorption of Pb2+ over Ni2+ onto the prepared adsorbent. Kinetics studies of single and binary systems showed that a pseudo-second order model could explain the adsorption processes well. Thermodynamic analysis results demonstrated that the adsorption of these metal ions on the prepared adsorbent is spontaneous and exothermic in nature. The adsorption capacity of MONPs-EG increased significantly in the presence of humic acids. Overall, the results of this study suggest that MONPs-EG can be used effectively as an adsorbent for heavy metals removal from aqueous solutions.

Zeolite Synthesized from Coal Fly Ash Produced by a Gasification Process for Ni2+ Removal from Water

There are increasing demands and great potential of coal gasification in China, but there is a lack of studies focused on the disposal and utilization of coal fly ash produced by the gasification process. In this study, a coal fly ash sample derived from a gasifier in Jincheng, China, was utilized as raw material for the synthesis of zeolite by alkali fusion followed by hydrothermal treatments. The effects of operation conditions on the cation exchange capacity (CEC) of synthesized zeolite were investigated. The synthesized zeolite with the highest CEC (270.4 meq/100 g), with abundant zeolite X and small amount of zeolite A, was produced by 1.5 h alkali fusion under 550 °C with NaOH/coal fly ash ratio 1.2 g/g followed by 15 h hydrothermal treatment under 90 °C with liquid/solid ratio 5 mL/g and applied in Ni2+ removal from water. The removal rate and the adsorption capacity of Ni2+ from water by the synthesized zeolite were determined at the different pH, contact time, adsorbent dose and initial Ni2+ concentration. The experimental data of adsorption were interpreted in terms of Freundlich and Langmuir equations. The adsorption of Ni2+ by the synthesized zeolite was found to fit sufficient using the Langmuir isotherm. More than 90% of Ni2+ in water could be removed by synthesized zeolite under the proper conditions. We show that the coal fly ash produced by the gasification process has great potential to be used as an alternative and cheap source in the production of adsorbents.

Thermodynamics of the adsorption of nickel ions from aqueous phase using graphene oxide and glycine functionalized graphene oxide

Adsorption capacity of Ni2+ on graphene oxide (GO) and glycine functionalized graphene oxide (GO-G) surfaces was well investigated and elucidated. Amino group was used to functionalizing agent for the surface modification of GO to GO-G. The effect of numerous influential parameters such as contact time, temperature and initial concentration of Ni2+ in the aqueous solution was well illustrated and optimized using batch adsorption study. The optimized values of adsorbent dose, initial concentration of Ni2+, contact time, and pH were found to be 20mg, 15mg/L, 50min, and 6 respectively, ongoing through the impact of temperature it was seen that, when the temperature was increased from 283 to 308K, the removal of Ni2+ by GO surface decreased but the removal of Ni2+ by functionalized GO-G surface decreased until 298K and after that it was increased. Adsorption isotherm study for the adsorption process was carried out using four types of the Langmuir and Freundlich isotherm models. Results clearly depict that adsorption of Ni2+ ions on to the GO adsorbent surface was well fitted and found to be in good agreement with the type (II) Langmuir isotherm model as the obtained regression constant value (R2) is found to be 0.999 while the adsorption of Ni2+ on GO-G surface was found to be in good agreement with the Freundlich isotherm model because the regression constant value (R2) is found to be 0.999.

Synthesis and selective recognition property of Ni2+‐imprinted microporous polymer beads

Nickel ion‐imprinted polymer (IIP) was synthesized from dimethylglyoxime and 4‐vinyl pyridine monomers. These functional monomers were self assembled with the Ni2+ template and then copolymerized with divinylbenzene and ethylene glycol dimethacrylate crosslinkers in toluene porogen via suspension polymerization. Imprinting was achieved by removing the template ion from the copolymers by extensive washing. The IIP particles produced were 300–700 µm in diameter and were spherical. The chemical and physical structures were characterized by Fourier transform infrared spectroscopy, energy dispersive X‐ray spectroscopy, and Brunauer–Emmett–Teller analysis. The adsorption capacity and kinetics, and separation selectivity were investigated using atomic adsorption spectroscopy in batch adsorption operation mode. The Ni2+‐imprinted polymers showed excellent adsorption ability and selective separation property. The adsorption capacity for Ni2+ was 320 µmol/g, and the selectivity factors (α) for Cu2+, Zn2+, Fe2+, and Cd2+ were 6, 11, 12, and 27, respectively. The adsorption capacity and separation selectivity were affected by the environmental pH, as the protonation easily took place in acidic condition. Copyright © 2013 John Wiley & Sons, Ltd.

Synthesis and Adsorption of Ni(II) on Ni(II)-Imprinted Polyaniline Supported on Attapulgite Modified with 3-Methacryloxypropyltrimethoxysilane

A novel Ni(II) ion-imprinted polymer [Ni(II)-IIP] was prepared by surface-imprinting technique using aniline as the functional monomer and 3-methacryloxypropyltrimethoxysilane (MPS)-modified attapulgite as the support material. The prepared sorbents were characterized by Fourier transmission infrared spectra, BET and scanning electron microscopy. The adsorption experiments carried out using Ni(II)-IIPs were optimized by changing the length of the polymer, contact time, solution pH, the concentration of template ion and the amount of cross-linking agent, etc. In addition, batch experiments were performed to evaluate adsorption kinetics and adsorption isotherms. The study results revealed that Ni(II)-IIPs had higher adsorption capacity and higher recognizing ability for Ni2+ compared with non-imprinted polymers. The experimental data fitted well with both the pseudo-second-order kinetic model and the Langmuir model. The maximum theoretical adsorption capacity for Ni2+ ions is 123.61 mg/g. The relative selec...

Study of the Textural Properties of Bovine Bones Char under Different Conditions

Environmental pollution is today a very important issue and the development of low cost materials and different sources need to be investigated. Our research group for several years she has been the development of adsorbent materials for industrial wastewater treatment and rivers. In this research compares the porosity developed by two different treatments using bovine bones to adsorb metal ions. Using bovine bones as raw material, two carbonized samples were obtained under different conditions. One of the carbonized samples was obtained in an oxidizing atmosphere at up to 600℃ for 2 hours. The other was obtained in an inert atmosphere at up to 800℃, during 2 hours. Different textural characteristics were obtained in each of the carbonized samples according to the conditions of synthesis. The carbonized sample obtained in the oxidizing atmosphere, CHUOX, produces a great pore distribution, with a significant mesopore volume, reflected in the hysteresis loop, while in carbonized bone obtained in an inert atmosphere, CHUN, a formation of micropores and mesopores smaller than that obtained in the other carbonized sample is observed. The surface area obtained is 130 m2 g-1 for CHUOX and 170 m2 g-1 for CHUN. Furthermore, the adsorption capacity of Ni2+ and Cu2+ ions from solution was measured for these two carbonized samples, and a higher retention of both ions in the carbonized sample obtained in the inert atmosphere was found, with values between 28.57 and 67.56 mg g-1. The immersion enthalpies of carbonized samples in ion solutions are determined with an exothermic effect for the solution-solid interaction.