Zinc Efficiency Research Articles

Membrane-assisted enrichment of zinc(II) from and into ammoniacal media through non-dispersive synergistic extraction

Abstract The enrichment of zinc(II) in ammoniacal media with non-dispersive synergistic extraction (NDSX) was achieved in a sandwich-supported liquid membrane module, in which a mixed extractant containing 4-ethyl-1-phenyl-1,3-octadione (HA) and trioctylphosphine oxide (TOPO) was used as the carrier. Several parameters of Zn(II) transport, including carrier concentration, diluent type, feed pH, total ammonia concentration, and temperature, were systematically investigated. The results showed that the mixing of TOPO with HA can effectively improve the Zn(II) enrichment from and into ammoniacal solutions. The transport efficiency of zinc increases with increasing carrier concentration and temperature. Moreover, Zn(II) transport is dependent on the total ammonia concentration and solution pH of the feed phase. The nonpolar n-octane is more beneficial to zinc transport than the polar octanol. Five successive transports exhibit excellent membrane stability and the effective uphill transport of zinc from and into ammoniacal media with NDSX.

Recycling Zinc and Preparing High-Value-Added Nanozinc Oxide from Waste Zinc–Manganese Batteries by High-Temperature Evaporation-Separation and Oxygen Control Oxidation

In this work, zinc was recycled and nanozinc oxide with high added values was prepared from waste zinc–manganese batteries by high-temperature evaporation-separation and oxygen control oxidation. Air was used as both the oxidant and the carrier gas. Because of the relatively fast oxidation rate of zinc, this Article attempts to balance the evaporation rate and oxidation rate of zinc by adding foreign materials to contend for the oxygen or covering the zinc with porous materials to isolate the oxygen. The results showed that the oxidation rate was still fast and the effect of contending for the oxygen by adding carbon powder or lead powder was not satisfied. The zinc hull was oxidized fast in the crucible and mixed with other oxides together, while covering the porous material (wire mesh, fiber felt) can accomplish the purpose of oxygen controlling. Zinc can be evaporated and separated from the zinc hull and oxidized during the zinc evaporation process, which is a benefit for producing pure nanozinc oxides. Under the experimental condition of 1123 K heating temperature, 3 kPa air pressure, and blowing air at 723 K, using fiber mat to cover the zinc hull, the recovery efficiency of zinc is ∼98.99%, and the uniform morphology of tetrapod-shaped nanozinc oxide was prepared successfully. This study provides a novel and environmentally friendly method for the resource utilization of zinc from waste zinc–manganese batteries.

Fine roots for uptake and translocation of zinc into young leaves as important traits for zinc efficiency of maize genotypes

ABSTRACT Suitable germplasm and breeding for zinc (Zn)-efficient genotypes has been prioritized to combat Zn deficiency problem. Six maize genotypes were grown in a nutrient solution with or without Zn to identify genotype tolerance to low Zn and its mechanism. Zhongnong 99 was found to be about 2-fold more Zn-efficient than L69 × 178. Young shoot Zn concentration and content was significantly correlated with Zn efficiency (ZE). Furthermore, Zn-efficient genotype as Zhongnong 99 distributed more Zn into young parts of shoot and also developed longer and thinner roots (≤ 0.2 mm) under -Zn conditions than inefficient genotypes. The close relationship (0.82***, 0.88***, 0.90***) between Zn content of young shoots and fine roots indicated that fine roots (≤ 0.2 mm) contributed more efficient Zn uptake into old parts which distributed to young parts. In conclusion, the analysis of young shoots and fine roots (≤ 0.2 mm) represent a suitable screening technique for ZE evaluation of under -Zn conditions.

Efficiency of Zinc and Calcium Ion Crosslinking in Alginate-coated Nitrogen Fertilizer

The work evaluated the difference of nitrogen retention in sodium alginate hydrogel microspheres with 50% of nitrogen, to allow the production of controlled release fertilizers. The crosslinking with the calcium and zinc ions occurs in a differentiated way, and it is emphasized that zinc binds more slowly and covalently. After the spheres were elaborated, a leaching test was performed to simulate the release of nitrogen by soil moisture. In this case, the zinc nitrate-reticulated beads showed a lower loss of the nitrogen content compared to calcium, with values of 6.7129% of nitrogen for zinc nitrate, corresponding to about 50% of the initial value, and 43.6345 % of nitrogen for calcium chloride corresponding to about 90% of the initial value. The characterization of the samples was performed by fourier transformed infrared (FTIR) analysis, and characteristic calcium and zinc alginate compounds were observed, in the same way as the connections caused by nitrogen. It can be defined that the zinc-crosslinked alginate obtained a lower swelling capacity and higher retention of nitrogen than with calcium chloride, being an alternative for the preparation of slow-release fertilizer. DOI: http://dx.doi.org/10.17807/orbital.v10i3.1103

Extraction of Heavy Metal Ions from Inorganic Wastewater

The results of studies on the extraction efficiency of zinc, copper, nickel, lead and cadmium ions by BAU-A, BAU-K and C-VERAD adsorbents are presented. From heavy metals, simulated wastewater was purified. The selectivity of adsorbents with respect to the heavy metals studied is shown. The results of the work can be used in the purification of inorganic industrial wastewater.

Influence of small amount of Mg incorporated into hexagonal ZnO crystal on cell performance in membrane free Zinc–Nickel redox battery

This study focused on improving the cell efficiency of Zinc–Nickel redox battery. The cycle life of zinc anodic material in KOH alkaline electrolyte was enhanced by small amount of Mg insertion into ZnO framework through a typical hydrothermal method. The as-prepared ZnO and MgxZn1−xO (x=0.001, 0.0025, and 0.005) anodic materials before and after charging/discharging test were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDX) to investigate the effect of inserted Mg ions on the zinc dendrite growth. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were utilized to examine the electrochemical performances of Mg-inserted ZnO as anodic material. The Mg-inserted ZnO–Ni membrane free redox batteries possess higher discharge voltage, higher cycle stability, lower corrosion current, and smaller charge-transfer resistance in comparison with bare ZnO. In addition, the redox cell efficiency was 85% in the ZnO anodic material inserted Mg of 0.0025mol even after 100 cycles.

Removal of Zinc from an Aqueous Solution Using Micellar-Enhanced Ultrafiltration (MEUF) with Surfactants

In the present study, the optimum conditions have been investigated for the separation of Zn2+ ions from aqueous media by micellar enhanced ultrafiltration (MEUF). For this purpose, optimum conditions for the concentration of surface active agent in the feed solution (sodium dodecyl sulfate, SDS), cetyltrimethyl ammonium bromide (CTAB), triton-X-100 (TX100)), filtering pressure, stirring rate and for the membrane porosity have been determined. It is shown that the filtering pressure has a significant effect on the permeate flux but a relatively insignificant impact on rejection of Zn2+. Permeate flux increased linearly with increasing pressure, ranging from 0.32 mLmin-1m-2 at 3 bar to 0.72 mLmin-1m-2 at 4 bar. The results showed that by adding SDS anionic surfactant, the permeate flux and the removal efficiency of zinc increased. Best results in terms of zinc rejection coefficient is 97.5 % at 5.0 x 10-4 M zinc concentration, 1.0 x 10-2 M SDS concentration (~x 8 cmc), stirring rate 500 rpm and transmembrane pressure 4 bar.

Comparative studies on acid leaching of zinc waste materials

Three industrial waste materials were characterized in terms of their elemental and phase compositions, leaching behaviour in 10% sulfuric acid solution as well as leaching thermal effects. Slag from melting of mixed metallic scrap contained about 50% Zn and 10% Pb. It consisted mainly of various oxides and oxy-chlorides of metals. Zinc spray metallizing dust contained about 77% Zn in form of zinc and/or zinc-iron oxides, zinc metal and Zn-Fe intermetallic. Zinc ash from hot dip galvanizing was a mixture of zinc oxide, metallic zinc and zinc hydroxide chloride and contained about 80% Zn. Dissolution efficiency of zinc from the first material was 80% (independently on the solid to liquid ratio, 50–150 kg/m3), while decrease of the efficacy from 80% to 60% with increased solid to liquid ratio for the two remaining materials was observed. Both increase in the temperature (20 °C to 35 °C) and agitation rate (300 rpm to 900 rpm) did not improve seriously the leaching results. In all cases, transfer of zinc ions to the leachate was accompanied by different levels of solution contamination, depending on the type of the waste. Leaching of the materials was exothermic with the similar reaction heats for two high oxide-type products (slag, zinc ash) and higher values for the spray metallizing dust.

Efficient extraction of copper and zinc from seafloor massive sulphide rock samples from the Loki’s Castle area at the Arctic Mid-Ocean Ridge

Seafloor massive sulphide (SMS) deposits have been identified as important marine metal resources for the future. However, literature on the recovery/extraction of metals from SMS is currently limited, and to date, no research has been published on the processing of SMS from the active hydrothermal vent field at the Arctic Mid-Ocean Ridge. In this paper extraction of copper and zinc, as economically important metals, from the seafloor massive sulphide rock samples from the Loki’s Castle area at the Arctic Mid-Ocean Ridge was investigated during nitric acid leaching. The results presented are of the various leaching experiments conducted under different conditions to optimise the extraction of copper and zinc. The mineralogical analysis indicated that the main copper and zinc bearing minerals were chalcopyrite and sphalerite, respectively. It was shown that the leaching efficiency and extraction of copper and zinc can be controlled mainly by temperature and acid concentration. The elemental composition and mineralogical data indicated that 95% of copper and zinc bearing minerals were leached out after 3 h, at the solid-to-liquid ratio of 1:10, temperature of 90 °C and acid concentration of 10%.

Zinc and selenium modulate barium-induced oxidative stress, cellular injury and membrane-bound ATPase in the cerebellum of adult rats and their offspring during late pregnancy and early postnatal periods

Context: Barium (Ba) may induce oxidative stress leading to tissues injury.Objective: Our study investigated the therapeutic efficiency of zinc (Zn) and selenium (Se) against neurotoxicity induced by Ba in adult rats and their progeny.Material and methods: Pregnant rats are exposed either to Ba (67 ppm), Ba + Zn, Ba + S or to only Zn and Se.Results: In Ba-treated rats, there was an increase of MDA, H2O2, AOPP levels and SOD activity in the cerebellum of dams and their pups, a decrease in GPx, CAT, AChE, Na+K+-ATPase and Mg2+-ATPase activities, GSH and NPSH levels. These changes were confirmed by histological damages. Co‐administration of Zn or Se to Ba-treated rats ameliorated the biochemical and histological aspects.Conclusion: Our results revealed that Zn and Se have shown promising effects against Ba toxicity in the cerebellum of adult rats and their suckling pups.

Breakage of sulfur crosslinks in styrene-butadiene rubber by zinc(II) dithiocarbimate derivative

The chemical structure of rubbers makes reprocessing quite difficult. In this work, the chemical regeneration was used for styrene-butadiene rubber recycling. As a first step, the rubber was compounded with commercial vulcanization additives on a roll mill. Rheometric and rheological parameters were obtained in a Rubber Process Analyzer (RPA 2000), and the composition was vulcanized and molded in a hydraulic press. The cured samples were characterized by mechanical tests (tensile strenght, tear resistance and hardness). Following this first step, zinc(II) dithiocarbimate complex was then mixed with the vulcanized rubber and devulcanization was carried out. Finally, the regenerated composition was revulcanized and properties obtained before and after the regeneration and revulcanization processes were compared. The results showed that low concentrations of zinc(II) dithiocarbimate complex favored its action as a vulcanization accelerator, producing elastomers with high values of torque, viscosity, modulus, hardness, tear resistance, and stress at break. Amounts in the range 4.0–8.0 phr favored its performance as a regeneration agent, giving rise to rubbers with low values of the already mentioned properties. Lastly, it was also observed that above 8.0 phr of the complex, the properties were further increased, indicating a supression of the regenerating efficiency of zinc(II) dithiocarbimate complex.

Efficiently enriching zinc(II) from and into ammonium chloride media with species regulation and Aliquat336

Abstract Solvent extraction of zinc(II) from and into ammoniacal chloride media with trialkylmethylammonium chloride (Aliquat336) has been investigated in the presence and absence of trioctylphospine oxide (TOPO). The results indicate that zinc extraction with Aliquat336 is sensitive to pH and ammonia concentration of ammoniacal chloride solutions. The extraction efficiency of zinc increases with increasing chloride concentration due to the formation of ZnCl 3 − species. Meanwhile, zinc can be effectively stripped with ammoniacal solutions from the loaded organic phases because of the formation of Zn(NH 3 ) 4 2+ species. The Aliquat336 mixed with TOPO can induce a synergistic effect on zinc extraction but antagonistic effect on ammonia stripping of zinc. Therefore, through adjusting the coordination equilibrium of zinc species in extraction and stripping processes, the efficient enrichment of zinc ions from and into the ammoniacal chloride media can be achieved by solvent extraction, which is beneficial for zinc recovery from the complex ore resources.

Zn (II) Removal from River Water Samples of Sembrong, Johor State, Malaysia by Electrokinetic Remediation

Heavy metals pollution has become one of the most serious environmental problems today. The treatment of heavy metals is of special concern due to their recalcitrance and persistence in the environment. Even many physical, chemical and biological treatment processes have been proposed to remove heavy metals from river water, the use of these treatment processes are not efficient and relatively costly. This study focused on the potential application of electrokinetic (EK) remediation in Sembrong River water to remove zinc (Zn2+). The physicochemical and biological parameters and water quality index (WQI) of Sembrong River water was characterized. The electrokinetic remediation experiments were performed by controlling pH, and electric density on voltage were observed and investigated. The results indicated that all physicochemical and biological parameters of Sembrong River complied with the standard discharged limit set by the Department of Environment (DOE). However, suspended solids (SS) and pH can be categorized as Class III according to INWQS. The best performance of 88% efficiency of zinc can be achieved EK experiment run at a fixed voltage of 30 V at pH 5.14 after 60 min of the process operate. This technology may be proposed for faster and eco-friendly removal of heavy metals in the environment.

ZnO/Si heterojunction solar cell fabricated by atomic layer deposition and hydrothermal methods

Abstract Currently, the first generation of silicon solar cells is dominating the photovoltaic market. Silicon cells are produced by various methods, which employ either crystalline or multi-crystalline substrates. However, both these manufacturing processes are expensive and potentially harmful to the environment and health. One example of this is that the surface is given its texture in a highly corrosive water solution of nitric and hydrofluoric acid. Additionally, both the diffusion and manufacturing of p-n junction and of metal contacts are associated with very high temperatures. This prompted us in our search for cheaper and more environmental friendly technologies. In this work, we discuss the possibility of producing components of photovoltaic cells by employing atomic layer deposition and hydrothermal technologies. This does not require the use of hazardous chemicals and high temperatures. The maximum efficiency of zinc oxide/silicon solar cells is 14% and 10% for textured and planar structures, respectively. A environmentally-friendly and simple procedure is thus being proposed, which, together with its relative efficiency, makes it an attractive alternative to the present procedure.

Increased adsorption of aqueous zinc species by Ar/O2 plasma-treated carbon nanotubes immobilized in hollow-fiber ultrafiltration membrane

Herein, we employed Ar/O2 plasma treatment technique to functionalize multi-walled carbon nanotubes (MWCNTs), thus to improve their dispersion capability and adsorption for cationic metal ions in water. The results indicate that plasma treatment significantly increased the surface oxygen content, and modified surface functionality of MWCNTs without damaging the integrity of nanotube patterns, thus, exhibiting superior dispersion and adsorption properties. Moreover, nanocomposite membranes were fabricated by incorporating functionalized MWCNTs inside a polymeric substrate membrane with hollow-fiber configuration. These membranes were studied for the adsorptive filtration of zinc (Zn2+) and other metal cations from synthetic and real water. The adsorptive removal efficiency of zinc by the composite membrane with functionalized MWCNTs remained at above 90%, regardless of water chemistry conditions. Unlike CNT adsorption of organics reported in the literature, the presence of natural organic matter (NOM) did not adversely affect zinc removal, indicating lack of competitive adsorption between zinc ions and NOM. Furthermore, the self-fabricated membranes effectively removed zinc and iron from a secondary wastewater effluent in the presence of common co-existing ions such as Na+, Ca2+, Mg2+, Mn2+ and Fe2+, illustrating the selective adsorption of Zn from wastewater. Importantly, the adsorption capability of CNT membranes for zinc was conveniently regenerated under acidic condition. This verified that the CNT membranes retained the original metal removal capacity even after five consecutive adsorption–desorption cycles.

Removal of Zinc by Bitter Orange Peels Activated Carbon and Commercially Activated Carbon, a Comparison Study.

In this study, a comparison between using activated carbon prepared from bitter orange peels (BOAC) and a common commercially activated carbon (CAC), which is brought from the market, as adsorbent materials. This study was designed to find out which of these two activated carbons is more effective in the removal of zinc from waste water. This work examines the use of bitter orange peels, which are available as waste in local markets and in household garbage as an alternative presage to prepare an activated carbon by using (H2SO4) as activating reagent. The effects of pH, initial zinc concentrations, treatment time, adsorbent media bed height and the flow rate of simulated synthetic aqueous solution (SSAS) on the removal efficiency of zinc were all studied under 24oC
 The results indicated that the removal efficiency of zinc increases with decreasing in pH of SSAS. When the initial concentration of zinc increases in SSAS, the removal efficiency of zinc was decreased. The study proved that the increasing of contact time leads to greater removal efficiency. When the height of adsorbent media in fixed column increases, the removal efficiency was increased. The experiments also showed that the removal efficiency of zinc from the SSAS increased, when the flow rate decreased. It could be concluded from this work that (BOAC) is better than (CAC) as an adsorbent materials in the removal of zinc; with a removal efficiency of (90%, 86%), respectively

Towards Zinc Biofortification in Chickpea: Performance of Chickpea Cultivars in Response to Soil Zinc Application

A field experiment was conducted at three locations in the southern region of Ethiopia during the 2012 and 2013 cropping seasons to evaluate chickpea cultivars for their response to soil zinc application, including agronomic performance, grain yield, grain zinc concentration, zinc and agronomic efficiency. Fifteen chickpea cultivars were evaluated in a randomized complete block design with three replications at each location and year. The highest number of pods (237) plant−1 was obtained from Butajira local landrace. The cultivar Naatolii produced the highest grain yield (2895 kg·ha−1), while the breeding line FLIP03-53C had the lowest yield (1700 kg·ha−1). The highest zinc concentrations of 47.5, 47.4, and 46.4 mg·kg−1 grain were obtained from the cultivar Arerti, and the two breeding lines FLIP07-27C and FLIP08-60C, respectively. The highest zinc efficiency (88%) was obtained from the Wolayita local landrace, whereas the highest agronomic efficiency of 68.4 kg yield increase kg−1 zinc application was obtained from the cultivar Naatolii. The current research identified chickpea cultivars with high grain zinc concentration, zinc efficiency, agronomic efficiency, and grain yield. The identification of cultivars with high grain zinc concentration allows the use of chickpea as a potential alternative to help to correct zinc deficiency, which is highly prevalent in the population of the region.

Influence of foliar-applied zinc in the form of mineral and complexed with amino acids on yield and nutritional quality of onion under field conditions

The aim of this field experiment was to investigate the efficiency of foliar-applied zinc (Zn) in the form of mineral (ZnSO4) and complexed with lysine (Lys), methionine (Met), or threonine (Thr) as a strategy to improve yield and nutritional quality of two onion cultivars (Allium cepa L. cvs. Behbahan and Perimavera). Different Zn sources and free amino acids (i.e., Lys, Met, and Thr) were applied once at the early rapid vegetative growth stage and once 45 d later at concentration of 0.5%. A control treatment (free of Zn and amino acids) was also used. Plant response to Zn foliar application varied depending on the cultivar and Zn sources. In ‘Behbahan’, foliar application of Zn from all sources significantly increased bulb yield while in ‘Primavera’, using ZnSO4 was ineffective. In both cultivars, the highest bulb yield was obtained by Zn-Lys complex. All Zn sources significantly increased Zn concentration in bulb, although the Zn-Lys complex was the most effective one. Foliar application of Zn-Lys complex resulted in a significant reduction of bulb nitrate accumulation while other Zn fertilizer sources had no significant effect on bulb nitrate content. In both cultivars, application of lysine either free or complexed with Zn significantly increased the bulb total soluble solids (TSS) compared with control while ZnSO4 had no significant effect on bulb TSS. In ‘Perimavera’, all Zn sources increased bulb pyruvic acid concentration while in ‘Behbahan’, only Zn-Lys and Zn-Met complexes were effective in increasing bulb pyruvic acid concentration. According to the results, Zn-Lys complex can effectively be used as foliar spray for improving yield and quality of onion in Zn-deficient calcareous soils.

Evaluation of Wheat Cultivars for Zinc Efficiency and Bio-fortification

Evaluation of Wheat Cultivars for Zinc Efficiency and Bio-fortification

Electrodeposition of compact zinc from the hydrophobic Brønsted acidic ionic liquid-based electrolytes and the study of zinc stability along with the acidity manipulation

Compact crystalline zinc was electrodeposited on stainless-steel electrode (SS) via potentiostatic/galvanostatic electrolysis from the hydrophobic Brønsted acidic ionic liquid, protonated betaine bis((trifluoromethyl)sulfonyl)imide (IL [Hbet][TFSI]), −based electrolytes containing ZnCl2 or ZnO under argon or ambient air atmosphere. Approximate 10wt% of propylene carbonate and water, respectively, were used as the co-solvents for [Hbet][TFSI] to form the IL-based electrolytes. The efficiency of zinc deposition/stripping, which is significantly affected by the Brønsted acidity of the IL-based electrolytes, was studied at glassy carbon electrode (GC) to evaluate the stability of the zinc electrodeposits along with the electrolyte acidity. The stability is very poor for the zinc electrodeposits obtained from ZnCl2 solution. However, it increases with increasing the quantity of ZnO or urea in the electrolytes; the former neutralize the dissociable protons in [Hbet] cations to form water, and the latter may form H-bonding with [Hbet] or be protonated to form the weakly acidic cations [HUrea]. Both suppress the reaction between the Zn electrodeposits and protons. The stability of the Zn electrodeposits, therefore, can be improved via the manipulation of the IL acidity.