Initial Copper Ion Concentration Research Articles

Removal of Cr(VI) from Water Using Attapulgite/Chitosan Composites

In this work attapulgite and chitosan were employed to prepare composites as eco-friendly adsorbent. Study on the adsorption efficiency of the adsorbent for Cr (VI) in aqueous solution was carried out. External factors such as the amount of attapulgite in the composites, initial concentration of Cr (VI), adsorption time and adsorbent dosage how to influence the adsorption efficiency of composites were investigated. The results showed that 0.63g adsorbent can reach maximum adsorption rate, which the mass ratio of attapulgite and chitosan is 0.8:1, the initial concentration of copper ions is 100mg / L and absorption time is 30min. Isotherm data fitted well to the Langmuir isotherm model.

Cu<sup>2+</sup> Removal by Hydroxyapatite Nanorods Prepared by Surfactant-Templated Method

Nanohydroxyapatite (HA) with rod-like shape was synthesized by a cationic surfactant-templated method. Batch adsorption experiments were conducted to investigate its copper adsorption property from aqueous solution. The effect of initial copper ion concentration and contact time were studied. Results showed that HA adsorption capacity increased from 25.6 mg/g to 81.4 mg/g with the increase of initial copper ion concentration from 20 mg/L to 200 mg/L. Meanwhile, the removal efficiency decreased from 64.1% to 20.3%. Moreover, it also revealed that the removal efficiency of Cu2+increased with the increasing contact time and the initial adsorption process is rapidly increased within 15 min and the equilibrium was attained after 15 min.

Thermodynamic behavior of adsorption of copper (II) ion on Wuyi Rock Tea Dreg

AbstractIn this study, the adsorption behavior of copper (II) ion on the dregs of Wuyi Rock affected by various parameters such as initial pH, adsorption time, reaction temperature and its initial concentrations were investigated. Wuyi Rock tea dreg shows a fine adsorbed ability for copper (II) ion. The adsorption equilibrium time was close to 60 min. The adsorption efficiency of copper (II) ion on Wuyi Rock tea dreg was sharply increased with the increasing reaction temperature. The pH value is a significant factor to influence the adsorption of the copper (II) ion on Wuyi Rock tea dreg compared with initial concentration of copper (II) ion, adsorption time, and temperature. The change of pHzpc of the tea dreg before and after copper (II) ion adsorption indicates that chemical adsorption plays a dominant mechanism. The optimal pH of 4.0 was found. Both models of Langmuir and the Freundlich could perform the experimental data conducted; however, Langmuir model had the better correlation coefficient than F...

Copper Cementation with Zinc Recovered from Spent Zinc–Carbon Batteries and Dissolution of Cement Copper in Hydrochloric Acid Solutions

In this study, the usability of waste zinc obtained from spent zinc–carbon batteries for copper cementation was examined. The effects of the initial concentration of copper ions, rotation speed of the zinc plate, initial pH of solution, and reaction temperature on copper cementation were investigated. It was determined that the cementation rate increased with increasing concentration of copper ions, rotation speed, reaction temperature, and initial pH of solution. It was found that the cementation reaction followed first-order kinetics and was controlled by diffusion. Copper powder produced by cementation was characterized using X-ray diffraction and scanning electron microscopy techniques. The dissolution of cement copper in hydrochloric acid solution was determined for the purpose of the production of copper(II) oxychloride. The effects of acid concentration, temperature, and stirring speed on the dissolution of cement copper were investigated. It was observed that the dissolution of copper powder increased with an increase in acid concentration, stirring speed, and temperature.

The single batch biosorption of copper(II) ions on Sargassum acinarum

In this study, the biosorption of copper(II) ions to Sargassum acinarum, a brown seaweed, was investigated in a batch system. The optimum biosorption conditions were determined as initial pH 5.5, temperature 25°C, initial copper(II) ion concentration 100 mg/L and biosorbent concentration 1.0 g/L. At the optimum biosorption conditions, the biosorption capacity of S. acinarum for copper(II) ions was found as 36.56 mg/g algae. The Langmuir and Freundlich isotherm models were applied to the biosorption data and the biosorption equilibrium was described well by the Langmuir isotherm model, with maximum biosorption capacity of 40.50 mg/g (0.637 mmol/g algae) of copper(II) ions. The intraparticle diffusion model and the pseudo-second-order kinetic model were applied to the experimental data in order to determine the removal mechanism and biosorption kinetic of copper(II) ions by S. acinarum. The pseudo-second-order kinetic model described very well the biosorption kinetic of copper(II) ions. Results showed that S. acinarum was an efficient biosorbent in the removal of copper(II) ions from an aqueous solution.

Biological Removing and Isothermal Absorption Studies of Copper by Fungal Biomass of Trichoderma

The environment suffers from the harmful effects of industrial pollution, including heavy metals. Nowadays, due to the low cost, high efficiency and environmental sustainability, biological techniques have been used to reduce or eliminate pollutants. Trichoderma species are free living fungi existing in the soil that produce antimicrobial materials. They inhibit the growth of pathogenic fungi and play a useful role in agriculture and ecosystem management. In this study, the uptake of copper ions was studied by three species of Trichoderma influenced by environmental variables such as the pH and the concentration of metal ions in a liquid medium containing potato extract and dextrose. Three different pH values (5, 7, 9) were selected for the solution and the initial concentration of copper ions was selected 1, 50, and 100 ppm. The remaining amounts of Cu in the media were measured after two months of exposure to pollutants with fungi; the measurements were performed using atomic absorption. Results showed that all three fungal species were able to absorb and reduce the amount of Cu in all three pH values; some case, their performances varied depending on the species as well as the culture conditions. T. harzianum species had the maximum efficiency for removing copper (79.92%), (3.94 mg/g, at fungal dry weight). Based on our results, the most efficiency of the three fungal species was obtained at the alkaline pH (78.09%). Also, Frindlych and Langmuir isotherm models were used to obtain isotherm equilibrium curves. Our results showed that the Langmuir isotherm model at pH 9 and the initial concentration of 50 ppm for copper ions was the most consistent.

The Uptake of Copper(II) Ions by Chelating Schiff Base Derived from 4-Aminoantipyrine and 2-Methoxybenzaldehyde

The Schiff base, 4-[(2-methoxybenzylidene)amino]-1,5-dimethyl-2-phenyl-1H-pyrizol-3(2H)-one (SB), was used for the first time to adsorb copper(II) ions in aqueous solution. Various parameters such as initial pH, agitation period and different initial concentration of copper(II) ions which influenced the adsorption capacity were investigated. The equilibrium adsorption data for copper(II) ions were fitted to Langmuir, Freundlich and Dubinin-Radushkevish isotherm models. The maximum monolayer adsorption capacity of SB as obtained from Langmuir isotherm was 5.64 mg/g. Kinetic data correlated well with the pseudo second-order kinetic model indicating that chemical adsorption was the rate limiting step.

MITIGATION OF METAL ION POLLUTION FROM INDUSTRIAL WASTE WATER USING WASTE WOOL

A study on the adsorption of copper (II) ions from the aqueous solution on waste wool had been carried out to analyze the adsorption capacity of waste wool, thereby aiming towards mitigation of metal ion pollution in industrial waste water. The effect of varying concentration of copper ions and varying time period, was studied on fixed weight of waste wool. The initial and final concentration of copper ions was measured by conductometric and spectrophotometric methods. Adsorption data were modeled with the langmuir and freundlich adsorption isotherms. The isotherm and first order equation were found to be applicable. Removal of metal ions using industrial waste wool is found to be favourable. Thus the work can be extended to study various physico-chemical parameters for removal of copper (II) ions from industrial effluents using waste wool. A later work can be involved where the waste wool adsorption parameter can be further utilized for composite ceramic products.

Preparation of Cu(II) ions adsorbent from acrylic acid‐grafted corn starch in aqueous solutions

AbstractAcrylic acid graft onto corn starch with excellent water holding capacity were successfully synthesized and employed for copper ions removal in aqueous solution. N,N′‐methylenebisacrylamide and potassium persulfate effectively worked as cross‐linking agent and the reaction initiator for copolymerization reaction, respectively. The data of FTIR confirmed that acrylic acid has been grafted onto starch. The effect of time on the water holding performance was investigated, and its maximum value was 96.6 g/g. The copolymers were dispersed in aqueous solution of Cu2+ ions and form polymer‐copper ions complex. The copper ions removal capacity of grafted starch was investigated by UV–visible spectrophotometry as a function of pH, water holding capacity, the content of NaCl, and the initial concentration of copper ions. In the presence of NaCl, the highest copper ions removal capacity was 2.56 mmol copper ions per gram of grafted starch, and 85.3% of copper ions have been removed. The isothermal study indicated that the adsorption data could be well modeled by Langmuir isotherms.

Low cost adsorbents obtained from ash for copper removal

We investigated the utilization of ash and modified ash as a low-cost adsorbent to remove copper ions from aqueous solutions such as wastewater. Batch experiments were conducted to determine the factors affecting adsorption of copper. The influence of pH, adsorbent dose, initial Cu2+ concentration, type of adsorbent and contact time on the adsorption capacity of Cu2+ from aqueous solution by the batch adsorption technique using ash and modified ash as a low-cost adsorbent were investigated. The optimum pH required for maximum adsorption was found to be 5. The results from the sorption process showed that the maximum adsorption rate was obtained at 300 mg/L when a different dosage of fly ash was added into the solution, and it can be concluded that decreasing the initial concentration of copper ion is beneficial to the adsorption capacity of the adsorbent. With the increase of pH value, the removal rate increased. When the pH was 5, the removal rate reached the maximum of over 99%. When initial copper content was 300 mg/L and the pH value was 5, the adsorption capacity of the zeolite Z 4 sample reached 27.904 mg/g. The main removal mechanisms were assumed to be the adsorption at the surface of the fly ash together with the precipitation from the solution. The adsorption equilibrium was achieved at pH 5 between 1 and 4 hours in function of type of adsorbent. A dose of 1: 25 g/mL of adsorbent was sufficient for the optimum removal of copper ions. For all synthesized adsorbents the predominant mechanism can be described by pseudo-second order kinetics.

The Research on Treating Waste Water Containing Copper by HAP

In this experiment, the copper-containing wastewater was adsorbed by HAP which was prepared by high temperature calcination after high temperature cooking fish scales. By the single factor experiments and orthogonal experiments, the optimal conditions were as follows: the initial concentration of copper ion was 200mg/L,the dosage of HAP was 0.2g,the reaction time was 30min,and pH was 5. The maximum removal efficiency was 98.23%.

Process Conditions and Kinetics for the Removal of Copper from Water by Electrocoagulation

Abstract The present study provides results from a study of the removal of copper from water through electrochemically generated Al3+ using aluminium alloy as the electrodes. Various operating conditions on the removal efficiency of copper were investigated, such as initial copper ion concentration, initial pH, current density, and temperature. Results showed that the optimum removal efficiency of 98.5% was achieved at a current density of 0.025 A/dm2, at pH of 7.0. Effects of co-existing anions such as carbonate, phosphate, silicate, and fluoride were studied on the removal efficiency of copper. Results of pilot scale study show that the process was technologically feasible. Adsorption of copper could be described by the Langmuir adsorption isotherm suggesting monolayer coverage of adsorbed molecules. First- and second-order rate equations, Elovich and Intraparticle diffusion models, were applied to study adsorption kinetics. The adsorption process follows the second-order kinetics model with good correl...

Studies on Removal of Low Content Copper from the Sea Nodule Aqueous Solution using the Cationic Resin TP 207

Selective removal of copper remaining in the raffinate, obtained after solvent extraction of copper with LIX 84-I from the sea nodule leach solution, containing 0.512 g/L Cu(II), 0.212 g/L Fe(III), 15.16 g/L Ni(II), and 2.012 g/L Co(II), was carried out with TP 207, in the batch and column adsorption system. The operational factors affecting the copper adsorption such as initial copper ion concentration (0.05–1.0 g/L), pH (1–4), resin dosage (5–100 g/L), and temperature (293–338 K) were investigated. Adsorption of copper was found to be maximum at an equilibrium pH of 1.97 without any adsorption of other metal ions in the solution and was strongly affected by the resin dosage. Adsorption equilibrium data was well fitted with the Langmuir isotherm, and the monolayer adsorption capacity of copper ion was determined as 68.7 mg g−1, at 298 K. The positive values of ΔHo (11.5, 10.4, and 10.1 kJ mol−1) determined at corresponding initial copper concentrations: 0.1, 0.3, and 0.5 g/L, respectively, in the solution, indicated that the adsorption was endothermic in nature. Kinetic studies confirmed that the adsorption of copper followed pseudo second order reaction with intra particle diffusion.

A critical study on the removal of copper by an electrochemically assisted coagulation: equilibrium, kinetics, and thermodynamics

ABSTRACTThe present paper provides an electrocoagulation process for the removal of copper from water through electrochemically generated Zn2+ using zinc as the anode and galvanized iron as the cathode. The different operating parameters on the removal efficiency of copper were investigated, such as initial copper ion concentration, initial pH, current density, and temperature. The results showed that the optimum removal efficiency of 96.6% was achieved at a current density of 0.05 A dm−2, at pH of 7.0. The effect of co‐existing anions such as arsenate, phosphate, boron, and fluoride were studied on the removal efficiency of copper. The results of pilot scale study show that the process was technologically feasible. The adsorption of copper, preferably fitting the Langmuir adsorption isotherm, suggests monolayer coverage of adsorbed molecules. First and second‐order rate equations, Elovich, and intraparticle diffusion models were applied to study adsorption kinetics. The adsorption process follows second‐order kinetics model with good correlation. Temperature studies showed that adsorption was endothermic and spontaneous in nature. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.

Study on the Removal of Copper Ions from Water Using Eco-Friendly Attapulgite/Chitosan Composites

In this work attapulgite and chitosan were employed to prepare composites as eco-friendly adsorbent. Study on the removal efficiency of the adsorbent for copper ions in aqueous solution was carried out. External factors such as the amount of attapulgite in the composites, temperature, initial concentration of copper ions, adsorption time and adsorbent dosage how to influence the removal efficiency of composites were investigated. The results showed that at room temperature, 0.37g adsorbent can reach maximum adsorption rate, which the mass ratio of attapulgite and chitosan is 1:1, the initial concentration of copper ions is 50mg / L and absorption time is 2h.

Separation of Copper Ions from Synthetically Prepared Electroplating Wastewater at Different Operating Conditions using Electrodialysis

The removal of ionic copper from electroplating wastewater was investigated using a five-compartment electrodialysis cell. The experiments were carried out using two different types of ion-exchange membranes (Purolite A500, Purolite PPC100). The effects of initial copper ions concentration, solutions conductivity, solutions pH on the duration of electrodialysis, massic flow (the amount of copper deposited on the cathode lead), and extraction percentage of copper ions were determinated. The electrodialysis unit operates under the constant applied voltage (7.5 V), with the electrolyte recirculation. When initial copper ions concentration is high (4 g/L), the extraction percentage of copper ions increased (>85%). Chemical stability of ion exchange membranes was investigated by Fourier transformed infrared spectroscopy. The results show that the membranes were not damaged during the electrodialysis, after three hours.

Removal of copper (II) from wastewater by heartwood powder ofAreca catechu: kinetic and equilibrium studies

Abstract The adsorptive behavior of heartwood powder of Areca catechu for copper(II) ion from synthetic wastewater has been investigated as a function of contact time, initial concentration of copper(II) ion, solution pH and biosorbent dosage, using batch method at room temperature. The optimum conditions for the metal adsorption were found to be at 0.5 g biosorbent dose, pH 5.5, and 30 min equilibrium time for the entire concentration range of the adsorbate. The equilibrium adsorption data were fitted to Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherm models and the model parameters were evaluated. The maximum adsorption capacity obtained from Langmuir isotherm model was found to be 9.578 mg g−1. The kinetic study showed that the pseudo-second-order kinetic model better described the biosorption process in comparison to pseudo-first-order, Elovich and intra-particle diffusion kinetic model. FT-IR spectrum analysis revealed that O-H, N-H and C-O groups present in the adsorbent were the p...

Synthesis of novel PVA crosslink mixed matrix scaffolds and adsorption of copper ions from waste water

Mixed matrix scaffolds were composed through uniform distributed of ion exchange resins (H+ form Amberjet, ID 780 &mgr;m) into the stereo-structural chitosan matrix prepared by dissolving chitosan powder with a middle molecular weight into acetic solutions. Along the synthesis processes of mixed matrix scaffolds, 4 wt% of chitosan solutions containing of resin particles were homogeneous crosslinked with aqueous polyvinyl alcohol (PVA) solutions to produce PVA crosslink mixed matrix scaffolds. Specifically, ion exchange resin particles suspending in a viscous PVA crosslink chitosan solution were poured into cylindrical aluminum containers to prepare PVA crosslink chitosan mixed matrix scaffolds through the freeze-gelation process. PVA crosslink mixed matrix scaffolds were then utilized for removal of copper ions from waste water. The uniform distribution of ion exchange resins embedded in the stereo structure of chitosan matrices can clearly be observed on the images of the scanning electron micrograph (SEM). The adsorption processes were operated by adsorbing copper ions of waste water onto the amine functional groups (–NH2) exposed on the external and porous stereo-structural surfaces of chitosan matrices as well as the sulfonate functional groups at the outer surface of ion exchange resins respectively. Adsorption experiment were carried out at 25°C and pH 6.0 over the concentration ranging from 200 to 3000 mg Cu2+/l. The maximum adsorption capacity for PVA crosslink mixed matrix scaffolds were 93.5 mg Cu2+/g-adsorbents at the initial copper ion concentration of 2500 mg Cu2+/l. The adsorption isotherm curve could be simulated by Langmuir adsorption model. The desorption ratio of copper ions of PVA crosslink chitosan mixed matrix scaffolds was 97.9% at a low initial copper ion concentration of 200 mg Cu2+/l. As the initial copper ion concentrations increased, desorption ratio decreased.

Recovery of metallic copper by integrated chemical reduction and high gradient magnetic separation

The recovery of metals from waste effluents is necessary for pollution prevention and sustainable practice. High gradient magnetic separation (HGMS) is seen as a viable method. We investigated the capture of valence copper from aqueous copper ion by HGMS in combination with a chemical reduction process. When a copper solution (3.9 or 15.6 mM) was exposed to excess of dithionite (mole ratio of 1:3) in the presence of ammonia (mole ratio of 4) and amended with MnCl2 (2.5 g/L) and the mixture passed through a flow reactor under a strong magnetic field (10000 Gauss), valence copper was obtained and captured in the reactor with well over 95% yields. The chemical reduction reactions were unaffected by the presence of MnCl2 while the amount of MnCl2 (0, 20 and 32 mM) has significantly varied the copper recovery efficiency, especially in the case of high initial copper ion concentration (15.6 mM). Formation of MnO2 flocs was found to have a detrimental effect on copper removal efficiency. The HGMS method offers a tool of resource recovery for copper from waste effluents.

Leaching copper from shredded particles of waste printed circuit boards

Leaching copper from shredded particles of waste printed circuit boards (PCBs) was carried out in sulfuric acid solution using hydrogen peroxide as an oxidant at room temperature. The influence of system variables on copper recovery by leaching was investigated, such as sulfuric concentration, amount of hydrogen peroxide addition, waste PBCs particle size, presence of cupric ion, temperature and time. The results shown that the optimum addition amount was 100mL 15 (wt%) sulfuric acid solution and 10mL of 30% hydrogen peroxide for leaching 10g waste PCBs powder with a solid/liquid ratio of 1/10 for 3h at room temperature (∼23°C). Moreover leaching temperature and initial copper ion concentration had insignificant effect on the leaching recovery of copper. The effect of different particle size of shredded waste PCBs on leaching of copper was investigated under the optimum leaching condition. The results revealed that shredding pieces of waste PCBs smaller than 1mm was efficient and suitable for copper leaching. Then the leaching solution was concentrated to crystallize CuSO4·5H2O, and crystal liquor was reused for the next cycles.