Extraction Of Cu Research Articles

Potentially Exploitable Reprocessing Routes for Recovering Copper and Cobalt Retained in Flotation Tailings

This research aimed at recovering metals retained in the tailings from the flotation of copper (Cu) and cobalt (Co) ores conducted at the New Concentrator in Kipushi (NCK). Metals retention in the tailings (0.73% Cu and 0.37% Co) increased due to the removal of the gravity separation section from the processing circuit together with changes arising in the feed mineralogical characteristics namely the increase in sulfide minerals. The concentrator’s feed was traditionally composed of oxidized minerals of Cu and Co from the Luiswishi deposit (DR Congo). Experiments conducted at the laboratory scale enabled identifying two exploitable routes for recovering metals retained in the tailings: firstly, the sulfuric acid leaching of tailings under reducing conditions in view of preparing a leach liquor (2.43 g/L Cu and 1.10 g/L Co) that can be utilized for cementing Cu, using iron chips and precipitating Co; secondly, the flotation of valuable minerals using xanthates in view of obtaining a rougher concentrate grading 1.43% Cu and 0.75% Co recovered at 56% and 59%, respectively, and later on, the obtaining of a cleaner concentrate assaying 3.97% Cu and 2.4% Co at the recoveries of 35% and 43%, respectively. The final concentrate enables the hydrometallurgical extraction of Cu and Co.

An experimental and theoretical analysis of supercritical carbon dioxide extraction of Cu(II) and Pb(II) ions in the form of dithizone bidentate complexes

An experimental and theoretical analysis of supercritical carbon dioxide extraction of Cu(II) and Pb(II) ions in the form of dithizone bidentate complexes

Selective extraction and separation of Li, Co and Mn from leach liquor of discarded lithium ion batteries (LIBs)

Novel route has been developed to selectively extract lithium (Li), cobalt (Co) and manganese (Mn) from the leach liquor of discarded lithium ion batteries (LIBs) containing 1.4 g/L Cu, 1.1 g/L Ni, 11.9 g/L Co, 6.9 g/L Mn and 1.2 g/L Li. Initially, Cu and Ni were extracted by solvent extraction techniques using 10% LIX 84-IC at equilibrium (Eq.) pH 3 and 4.6, respectively. Subsequently, precipitation studies were carried out at different conditions such as pH, reaction time, precipitant concentration etc., to optimize the parameters for selective precipitation of Co from the leach liquor. Result showed that 99.2% Co was precipitated from the leach liquor (11.9 g/L Co, 6.9 g/L Mn and 1.2 g/L Li) after extraction of Cu and Ni in a range of pH 2.9 to 3.1 using un-diluted ammonium sulfide solution (10% v/v) as a precipitant at 30 °C, while only 0.89% Mn and 0.62% Li were co-precipitated. After Co precipitation, 98.9% Mn was extracted from the filtrate using 10% D2EHPA at equilibrium pH 4.5, and Li remained in raffinate. From the obtained purified solution, metals could be recovered either in a form of salt/metals by precipitation/ evaporation/ electrolysis method.

Hydrophobic Deep Eutectic as a New Solvent for Liquid-Liquid Extraction and Its Potential Application in Ligandless Extraction of Cu (II)

Background: The cost-effective and environmentally benign solvent of hydrophobic deep eutectic (DES) was prepared for the removal of Cu (II) from aqueous solution. Hydrophobic DES has been gaining increasing attention from researchers for the replacement of hazardous solvent consumption in liquid-liquid extraction (LLE). Objectives: To synthesize the hydrophobic DES and optimize the parameters for ligandless LLE using DES, and LLE with DES-LIG, respectively. Materials and Methods: The fatty acid-based DES was prepared using a mixture of capric acid (C10) and lauric acid (C12) as a potential solvent for the extraction of Cu (II). The DES was characterized via FT-IR, NMR, and TGA. The removal percentage of Cu (II) was compared between ligandless LLE and other conventional LLE techniques. DES was used as the solvent in the ligandless LLE, while 1,10-phenanathroline ligand with DES (DES-LIG) was used in the conventional LLE techniques. The optimized parameters such as pH, initial concentration, and contact time for Cu (II) removal were studied and analyzed using atomic absorption spectroscopy (AAS). Results and Discussion: The ligandless LLE with DES demonstrated the highest removal percentage of Cu (II) at optimum conditions of pH 8, initial concentration of 80 μg mL-1, and contact time of 45 minutes. Conclusion: The removal of Cu (II) was more effective in ligandless LLE using DES.

Enhanced extraction of copper from electronic waste via induced morphological changes using supercritical CO2

Electronic waste (e-waste) is one of the fastest growing waste segments in the world. This study investigates the use of supercritical CO2 (scCO2) and aqueous acid as co-solvent for the treatment of e-waste, specifically for the extraction of copper. Printed circuit board (PCB) was selected as the e-waste of study. In order to perform controlled experiments, melt-pressed Cu foil and polycarbonate sheets were prepared as surrogates for PCBs. It was found that a scCO2 and acid pre-treatment induced drastic morphological changes in the polymer, creating pores, cracks, and delamination. This finding was translated to the actual waste PCB system. This unique process involved the pre-treatment of the PCB with scCO2 and aqueous sulfuric acid at 120 °C and 148 atm for 30 min followed by leaching of the treated PCB in a solvent containing 2 M sulfuric acid and 0.2 M hydrogen peroxide at ambient conditions. Experimental results showed that 82% of the copper contained in the PCB was extracted in under 4 h. The characterization of the PCB demonstrated that the pre-treatment with scCO2 and acid induced the crystallization of the plastics (polymer component), creating pores and weakening the structure of the PCB, thereby enhancing the transport of the solvent to the buried metal interfaces. This novel process using scCO2 could reduce physical processing (e.g. grinding of the PCB) and acid usage during the extraction of Cu from e-waste, providing a greener alternative for current methods of recycling of metals, which are energy intensive with large environmental footprints.

Selective electromembrane extraction and sensitive colorimetric detection of copper(II)

Abstract In this study, an extremely effective electromembrane extraction (EME) method was developed for the selective extraction of Cu(II) followed by Red-Green-Blue (RGB) detection. The effective parameters optimized for the extraction efficiency of EME include applied voltage, extraction time, supported liquid membrane (SLM) composition, pH of acceptor/donor phases, and stirring rate. Under optimized conditions, Cu(II) was extracted from a 3 mL aqueous donor phase to 8 µL of 100 mM HCl acceptor solution through 1-octanol SLM using an applied voltage of 50 V for 15 min. The proposed method provides a working range of 0.1–0.75 µg·mL−1 with 0.03 µg·mL−1 limit for detection. Finally, the developed technique was applied to different environmental water samples for monitoring environmental pollution. Obtained relative recoveries were within the range of 93–106%. The relative standard deviation (RSD) and enhancement factor (EF) were found to be ≤4.8% and 100 respectively. We hope that this method can be introduced for quantitative determination of Cu(II) as a fast, simple, portable, inexpensive, effective, and precise procedure.

Pressure leaching of selenium and tellurium from scrap copper anode slimes in sulfuric acid-oxygen media

Copper anode slimes are essential secondary resources from which valuable metals, such as Cu, Se, Te, Au, and Ag, may be recovered. Herein, oxidation pressure leaching is proposed for the pretreatment of copper anode slimes to realize efficient extraction of Cu, Se, and Te and enrichment of Au and Ag in the leaching residue. Detailed investigations were conducted to determine the effects of sulfuric acid concentration, liquid-to-solid ratio, oxygen partial pressure, and reaction temperature on the recovery of Cu, Se, and Te. Results of thermodynamic analyses indicate that high pH values enhanced the transformation of insoluble Se2− into soluble HSeO3−, whereas low pH environments favored the presence of soluble Te(OH)3+. During the first stage of oxygen pressure leaching in H2SO4 (0.5 mol/L) with a liquid-to-solid ratio of 10 mL/g, the leaching ratios of Cu, Se, and Te were 99.54%, 96.95%, and 68.54%, respectively. The results of the SEM-EDS and MLA analyses of the first-stage pressure leaching residue indicate that the remaining Se and Te existed as Ag2Se and TeO2 phases, which were further dissolved in a H2SO4 solution (1 mol/L) with a liquid-to-solid ratio of 20 mL/g to obtain Se and Te leaching ratios of 99.5% and 98.6%, respectively.

Application of the Taguchi Method and Central Composite Design for the Highly Selective and Efficient Extraction of Cu(II) ions from an Aqueous Solution Containing Mn(II), Co(II), Ni(II), Zn(II), Cu(II), and Pb(II) ions Mixture Using Benzyl Bis(thiosemicarbazone)

A simple method was developed for the highly selective and efficient extraction of Cu(II) ions from an aqueous source solution containing Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and Pb(II) ions using benzyl bis(thiosemicarbazone) (LH2) as the chelating agent. The parameters involved in selectivity and efficiency of extraction were concurrently investigated by multivariate optimization methods with rapidity and reliability. First, the organic solvent (A = Chloroform, 1,2-dichloroethane, dichloromethane, nitrobenzene), extraction time (B = 2, 6, 10, 14 h), pH (C = 3.6), shacking rate (D = 320,560 rpm), and LH2 concentration (F = 0.0001, 0.0005 mol/L) influence on selectivity of the system were investigated using the Taguchi design. The obtained results reveal that B, D, and F have notable effects on the selectivity of the extraction procedure, whereas the A and C presented little influence. Then, to maximize the percentage of Cu(II) ion extraction, the significant parameters were further optimized using central composite design (CCD). Eventually, optimum conditions were achieved as dichloromethane, 12 h, 6, 400 rpm, and 1 × 10−3 mol/L for A, B, C, D, and F, respectively. At the above-specified conditions, Cu(ΙΙ) ion with acceptable high recoveries was extracted from the mixed cations solution, while other cations remained in the source phase. In this work, by the right choice of the extraction conditions, a general chelating agent has been converted to a highly selective and efficient chelating agent for Cu(II) ions. The high selectivity and efficiency of this method make it suitable for the successful extraction of Cu(ΙΙ) ion in various real samples with the recoveries ranged from 91.27 to 99.20%.

Preparation of polyacrylonitrile/polyindole conducting polymer composite and its use for solid phase extraction of copper in a certified reference material.

A polyacrylonitrile/polyindole (PAN/PIN) [50, 50] conducting polymer composite was chemically synthesized using FeCl3 as an oxidizing agent in chloroform solution and nitrogen atmosphere at 10 °C. The formation of the composite was supported by Fourier transform infrared spectroscopy. The morphological properties of the composite were investigated by atomic force microscopy and scanning electron microscopy. The thermal properties of the composite were examined by using thermogravimetric analyses. It was found that the composite had good thermal stability. The conducting polymer composite was used for the first time as an adsorbent for solid phase extraction of Cu (II). The optimum pH was found to be 7. The adsorption and elution shaking times were 5 and 15 min, respectively. The elution was done with 5 mL of 2 mol L-1 HNO3. The accuracy of the developed method was confirmed by analyzing certified reference material (TMDA-70.2 Lake Water).

Biochar Affects Heavy Metal Uptake in Plants through Interactions in the Rhizosphere

Heavy metals in soil pose a constant risk for animals and humans when entering their food chains, and limited means are available to reduce plant accumulation from more or less polluted soils. Biochar, which is made by pyrolysis of organic residues and sees increasing use as a soil amendment to mitigate anthropogenic C emissions and improve agronomic soil properties, has also been shown to reduce plant availability of heavy metals in soils. The cause for the reduction of metal uptake in plants when grown in soils enriched with biochar has generally been researched in terms of increased pH and alkalinity, while other potential mechanisms have been less studied. We conducted a pot experiment with barley using three soils differing in metal content and amended or not with 2% biochar made from Miscanthus x giganteus, and assessed plant contents and changes in bioavailability in bulk and rhizosphere soil by measuring extractability in acetic acid or ammonium nitrate. In spite of negligible pH changes upon biochar amendment, the results showed that biochar reduced extractability of Cu, Pb and Zn, but not of Cd. Rhizosphere soil contained more easily extractable Cu, Pb and Zn than bulk soil, while for Cd it did not. Generally, reduced plant uptake due to biochar was reflected in the amounts of metals extractable with ammonium nitrate, but not acetic acid.

Precious Metals Recovery from Waste Printed Circuit Boards by Gravity Separation and Leaching

ABSTRACT This study focuses on the recovery of valuable metals, such as gold, silver, and copper, from the printed circuit boards of waste computers, using physical separation followed by leaching methods. Characterization studies revealed that resins and glass fibers were attached as grain together with base and precious metals. A hammer mill was employed as a second stage crusher to disintegrate the different components of the printed circuit board, thus improving the selectivity and recovery of metals. Separation studies using a laboratory-scale shaking table showed that 33% of the feed was removed as a light product and 96.8% of Au, 96.7% of Ag, and 97.7% of Cu were recovered in heavy fraction. Leaching the light fraction using 3 M H2SO4 and 0.33 M HNO3 at 80°C for two h resulted in greater than 90% extraction of Cu. Au and Ag were dissolved at room temperature with a leaching solution of 0.2 M S2O3 2-, 0.02 M CuSO4, and 0.2 M NH3.H2O, which provided a recovery of more than 59% of Au and 98% of Ag within eight h. Direct leaching tests using optimized conditions were also implemented on the crushed sample, and 45% of Au, 87.6% of Ag, and 70.8% of Cu were extracted.

Synthesis and characterization of Fe3O4@polythionine-Au for the removal and pre-concentration of Cu(II) from marine samples

The extraction of Cu(II) ions in marine samples was performed by nanocomposite of magnetic polythionine-Au, as an efficient magnetic extraction phase. For characterization of the prepared materials, different methods including FT-IR, SEM, EDX, TEM and VSM were used. The magnetic polythionine-Au nanocomposite exhibited higher adsorption percentage (98%) than the magnetic polythionine (65%) for uptake of Cu(II) ions. The optimized parameters for magnetic solid-phase extraction procedure were as sample pH of 7, sorption time of 10 min, sorbent dosage of 30 mg, elution solvent (2 mL) of HNO3 (0.3 mol L−1)/thiourea (1% w/v) and breakthrough volume of 300 mL. The adsorption kinetic follows a pseudo-second-order kinetic model and well fitted with the Langmuir isotherm model. The adsorption capacity was 120 mg g−1 for Cu(II). Also, the effect of thermodynamics of adsorption process was discussed. The nanocomposite adsorbent can be used for five cycles without significant decrease in adsorption capacity. The calibration curve was linear in the concentration range of 0.7–50 μg L−1 (R2 = 0.9983). The limits of detection and quantification were achieved as 0.097 and 0.32 μg L−1, respectively. The real samples were a gastropod from the Persian Gulf (Trochus erithreus), and muscle tissues of a fish (Trout) and shrimp. Good relative spiked recoveries (95–105%) were obtained for the real samples.

Selective extraction of Cu+ and Cu2+ ions from mushroom and lichen samples prior to analysis by micro-volume UV-Vis spectrophotometry: Application of a novel poly (SMIm)-Tris-Fe3O4 nanocomposite

In this study, a novel poly (SMIm)-Tris-Fe3O4 nanocomposite was prepared for selective extraction of Cu+ and Cu2+ ions by ultrasound assisted-cloud point extraction (UA-CPE). The nanocomposite was characterized by analysis of ATR-FT-IR, 1H NMR and XRD. After optimization of the extraction conditions, the copper ions were independently detected against sample blank at 347 nm by micro-volume UV–vis spectrophotometer. Under the optimal conditions, good linear relationship was obtained in the ranges of 0.3−150 and 10−350 μg L−1 for each ion at pH 7.0 and pH 5.0, respectively, with a better regression coefficient than 0.992. The method detection limits, accuracy and precision were 0.095 and 3.03 μg L−1, 91.5−96.0 % and 93.0−98.5 %, and 2.5–4.5 and 3.8–7.1 % (n:5, 25 and 100 μg L−1) for Cu+ and Cu2+ ions, respectively. A preconcentration of 70-fold was obtained from 35-mL of sample. After validation, the method was successfully applied to determination of total Cu levels in lichen and mushroom samples after pre-reduction at pH 7.0, and the recoveries in the range of 90−96 % were obtained by two calibration approaches after spiking with 10 μg L−1. The results were also statistically compared with those obtained by FAAS analysis to ensure accuracy and precision.

A polymer inclusion membrane for the simultaneous determination of Cu(II), Ni(II) and Cd(II) ions from natural waters

A novel polymer inclusion membrane (PIM), doped with pyridine-2-acetaldehyde benzoylhydrazone (2-APBH) as extractant, was synthesized and applied for the simultaneous extraction and preconcentration of Cu(II), Ni(II) and Cd(II) ions from natural waters of different salinities. Poly(vinyl chloride) (PVC) and tributyl phosphate (TBP) were used to prepare the polymeric membrane. The carrier-mediated extraction of Cu(II), Ni(II) and Cd(II) ions by PIM was based on the reaction of 2-APBH as a polydentate ligand, forming uncharged chelates at pH 8. After a back-extraction step from the membrane to an acid solution (0.3 mol L-1 nitric acid), these ions were quantitative determined by flame atomic absorption spectroscopy. The optimum values of different analytical variables were determined by using the modified simplex method. The results showed limits of detection of 0.33 µg L-1 for Cu(II), 0.75 µg L-1 for Ni(II) and 0.48 µg L-1 for Cd(II). The accuracy was successfully assessed by analyzing a certified reference river water (LGC 6019). The applicability of the proposed PIM on real samples was also demonstrated on estuarine and seawater samples, with high salinities.

Separation of cobalt, nickel and copper with task-specific amido functionalized glycine-betaine-based ionic liquids

Task Specific Ionic Liquids (TSILs) were generated by association between a cationic amido functionalized analogues of glycine-betaine (AGB) and coordinating anions such as dicyanamide (Dca−), 4-chlorosalicylate (ClSal−), saccharinate (Sac−) and weak coordinating one such as bis(trifluorosulfonyl)imide (Tf2N−). Extraction of Cu(II), Ni(II), Co(II), from pure water and salt media was performed with these AGB-ILs at room temperature. The obtained results show that in pure water Clsal based AGB-ILs have a high extraction efficiency towards these metals, whereas dicyanamide based AGB-ILs may extract efficiently Cu(II). In some cases, extraction can be improved by using simple chaotropic salts or intermediate anion such as NO3− or Cl−. Co(II) may be quantitatively extracted by Dca based AGB-ILs in NaCl 4 mol L−1. The rational use of background salts can improve the selectivity of the extraction process and allow the separation and the recovery of the three metals separately from a mixture containing two or three divalent metals. The metal could be back-extracted from the ionic liquid phase with aqueous solution of Na2SO4, limiting the release of ionic liquid cation in aqueous media, thus preserving its integrity. The metal extractability by the Dca based ionic liquids after the stripping is quasi-equivalent to that of the fresh AGB-IL showing that it can be reused for three or four extraction and stripping cycles. A regeneration of Dca based ionic liquids after several extraction cycles is made possible by adding a solution of NaDca which restore their extractive capacity.

Extraction of Cu, Fe, Mn, and Ni from Margarine Samples Using Extraction Induced by Emulsion Breaking Procedure Prior to Graphite Furnace Atomic Absorption Spectrometry and Comparison of Results to Provisional Tolerable Daily Intake Values.

The emulsion induced by emulsion breaking (EIEB) procedure was previously reported for the extraction of copper, iron, manganese, and nickel from liquid oil samples such as vegetable oil. To optimize the EIEB procedure for determination of copper, iron, manganese, and nickel in solid oil (margarine) samples by Graphite Furnace Atomic Absorption Spectrometry (GFAAS). The extraction procedure uses a surfactant in nitric acid to form an emulsion followed by heating to break the emulsion. Optimization included variation of the test portion size, the type and concentration of the surfactant, the concentration of nitric acid in the aqueous solution, the emulsion agitation time, heating temperature, and the time required to break the emulsion. Mean element concentrations of 11 margarine samples were in the following ranges: Cu 0.031-0.131 µg/g, Fe 5.7-24.9 µg/g, Mn 0.542-1.11 µg/g, and Ni 0.108-0.134 µg/g. Under the optimized extraction conditions, the detection limits (µg/kg) were 4.8, 13, 1.5, and 23 for Cu, Fe, Mn, and Ni, respectively. The accuracy of the extraction procedure was determined by comparison to commonly used microwave digestion procedure. The EIEB results were not statistically different from the microwave digestion results when analyzed by GFAAS as determined by the statistical tests. The EIEB procedure was shown to be equivalent to the commonly used microwave digestion procedure for extraction of analytes from margarine samples. The optimized EIEB extraction procedure is simple, rapid, low cost, and environmentally friendly. It has improved detection limits and allows calibration with aqueous standards.

Neural network prediction of bioleaching of metals from waste computer printed circuit boards using Levenberg‐Marquardt algorithm

AbstractThe applicability of artificial neural network (ANN) to predict the bioleaching of metals using from computer printed circuit boards (CPCB) and the influence of process parameters were studied. The influence of process parameters initial pH (1.6‐2.4), pulp density (2%‐13%), and the initial volume of Inoculum (5%‐25%) were investigated on the rate of bioleaching of metals from CPCB. Network inputs were fed as initial pH, pulp density, and inoculum volume and with the extraction of Cu, Ag, and Au as output. The ANN was developed using the Levenberg‐Marquardt algorithm and trained for modeling and prediction. The most fitting architectures for Cu, Ag, and Au were [4‐5‐5‐2‐1], [4‐7‐5‐2‐1], [4‐7‐1‐1‐1] trained with Levenberg‐Marquardt algorithm, respectively. The R values were observed to be 0.996, 0.997, and 0.993 for Cu, Ag, and Au extraction predictions, respectively. The genetic algorithm model defined by ANN was used to achieve maximum extraction rates for Cu, Au, and Ag. The predicted data showed that there is a great capability of using ANN for the prediction of Cu, Ag, and Au extraction from CPCB through bioleaching process. Hence, the ANN model can be used to control the operational conditions for improved metals extraction through bioleaching.

Extraction and stripping of Cu and Ni from synthetic and industrial solutions of Sarcheshmeh Copper Mine containing Cu, Ni, Fe and Zn ions

Abstract The extraction and stripping of Cu and Ni ions from synthetic and industrial solutions of Sarcheshmeh Copper Mine containing Cu (770 mg/L), Ni (3200 mg/L), Fe (800 mg/L) and Zn (200 mg/L) were comprehensively investigated using D2EHPA, LIX 984, Cyanex 302, Chemorex CP 150 and Acorga 5774 diluted in kerosene. The influential parameters such as mixing speed and time, concentration of extractant, pH and temperature were considered in extraction stage. Furthermore, stripping of Cu and Ni was examined using different inorganic and organic acids (sulfuric, hydrochloric, nitric and citric acids) with different concentrations. The results indicated that the highest extractions of Cu and Ni occurred within 3 min, with the mixing speed of 500 r/min, 28 °C and A/O ratio of 1:1. Moreover, Cu was extracted by LIX 984 at the concentration of 10% (v/v), whereas Ni was extracted by Cyanex 302 at the concentration of 30% (v/v), efficiently. The optimal pH for Cu and Ni extraction is in ranges of 2−3 and 4−5, respectively. Cu and Ni were selectively extracted with the recoveries of 85%, 93% and 77%, 82% from synthetic and industrial solutions containing Ni, Cu, Zn and Fe ions, respectively. The results of optimal condition showed that 96% of Ni and 93% of Cu were stripped from the synthetic and industrial solutions. Finally, four elements Zn, Fe, Cu and Ni were extracted in three stages with D2EHPA, LIX 984 and Cyanex 302 extractants respectively with the least impurities.

Coupling phytoremediation efficiency and detoxification to assess the role of P in the Cu tolerant Ricinus communis L.

Phosphorous (P) fertilization is an important agronomic practice, but its role in enhancing phytoremediation efficacy and mediating detoxification has rarely been reported in environmental remediation studies. In this study, a pot experiment was undertaken to assess: firstly, the effect of P on phytoextraction of Cu by Ricinus communis L.; secondly, the potential mechanisms by differentiating the effects of the plant from that of P fertilizer (Ca(H2PO4)2); and thirdly, the role of P in physiological detoxification. Results showed that the application of P fertilizer significantly (p ≤ 0.05) increased the plant biomass as well as the Cu concentrations in plant tissues. This enhanced the phytoremediation efficiency represented by the total Cu extraction (up to 121.3 μg Cu plant−1). Phosphorous (P) fertilizer led to a negligible decline in soil pH (0.2 units) but significantly (p ≤ 0.05) reduced the concentrations of soil available in Cu and Fe, due to the formation of insoluble Cu/Fe-phosphate precipitates. Nevertheless, P fertilizer still improved the accumulation and extraction of Cu by R. communis, most likely attributable to the Fe-deficiency induced by applied P fertilizer. Moreover, the application of P fertilizer revealed a significant reduction in MDA, and a profound (p ≤ 0.05) elevation in the amount of photosynthetic pigments, GSH and AsA, along with the enhanced activities of antioxidative enzymes (SOD, POD, and CAT). In this way, Cu toxicity was alleviated. P fertilizers not only enhance the phytoremediation efficiency of Cu-contaminated soils by R. communis, but they also facilitate detoxification, which improves our understanding of the role of P in phytoremediation technologies.

Silica Gel‐Immobilized 5‐aminoisophthalohydrazide: A novel sorbent for solid phase extraction of Cu, Zn and Pb from natural water samples

A novel silica sorbent, silica gel‐immobilized 5‐aminoisophthalohydrazide (SiO2‐APH), was prepared by the condensation of 3‐chloropropyl‐functionalized silica gel with 5‐aminoisophthalohydrazide (APH) derived from dimethyl 5‐aminoisophthalate as a starting material and used for separation and preconcentration of Cu, Zn, and Pb metals in water samples using Flame Atomic Absorption Spectrometry (FAAS). The characterization of the new sorbent was carried out by Elemental Analysis, Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). Important analytical parameters including as pH, amount of sorbent, type and amount of eluting solvent, sample volume, vortex and ultrasonic bath time, matrix ions that effect the developed SiO2‐APH‐solid phase extraction (SPE) method were investigated and optimum parameters were detected. Recoveries of examined metals were obtained as 98% for Cu and Pb and 101% for Zn. The relative standard deviation (RSD, n = 8) of Cu, Zn and Pb metals were 3.2, 2.8 and 1.6%, respectively. Limit of detections (LODs) (n = 10) were found as 2.7 μg L−1 for Cu, 7.4 μg L−1 for Zn and 3.5 μg L−1 for Pb μg L−1. The accuracy of the new method was assessed by analyzing of TMDA‐51.4 and TMDA‐70.2 certified reference materials. The results obtained for metals were in a good agreement with certified values. Addition/recovery test was applied to the real well, river, dam and stream water samples to check the accuracy of the method. The results showed that the developed SiO2‐APH‐SPE method can be effectively used as an alternative method for determination of Cu, Zn, and Pb metals in water samples.