An environmentally friendly system for high efficient silver recovery from anode slime

2019 ◽  
Vol 116 (2) ◽  
pp. 208 ◽  
Author(s):  
Li Xiao ◽  
Peng Qian ◽  
Yang Yu ◽  
Peiwei Han ◽  
Yongliang Wang ◽  
...  
Keyword(s):  
Sodium Thiosulfate ◽  
Anode Slime ◽  
The Novel ◽  
Solution Ph ◽  
Silver Recovery ◽  
Oxidant Concentration ◽  
Conversion Rates ◽  
High Efficient ◽  
Silver Dissolution ◽  
Thiosulfate Concentration

Anode slime is an extremely valuable secondary resource for the recovery of silver and has attracted wide attentions. Effective metal recovery is usually constrained by either environmental hazards or high consumption of lixiviant for cyanide and non-cyanide leaching reagents. To tackle these issues in the process of silver recovery from anode slime, this research demonstrated a new leaching system with using an efficient oxidant which encapsulates cyanide into ferric complexes to ensure it not releasing into the environment while effective silver recovery was achieved. Comparing with the traditional tetra-amine copper oxidant, it was found that the dissolution rate of silver was significantly improved and leachate consumption was largely decreased. The effects of stirring speed, sodium thiosulfate concentration, oxidant concentration, solution pH and time on silver dissolution were investigated. When the novel system of iron-encapsulated cyanide was applied to extract silver from anode slime, the final conversion rates of silver was 97% after 60 minutes. This system has great potential in silver recovery from anode slime.

scholarly journals Multiresidue Analytical Method for the Determination of Eight Penicillin Antibiotics in Muscle Tissue by Ion-Pair Reversed-Phase HPLC after Precolumn Derivatization

1999 ◽  
Vol 82 (5) ◽  
pp. 1083-1095 ◽  
Author(s):  
Eric Verdon ◽  
Pierrick Couëdor
Keyword(s):  
Muscle Tissue ◽  
Phosphate Buffer ◽  
High Performance ◽  
Solid Phase ◽  
Sodium Thiosulfate ◽  
Reversed Phase ◽  
Extraction Column ◽  
Precolumn Derivatization ◽  
Solution Ph

Abstract A high-performance liquid chromatographic multiresidue method was developed for the determination of 8 penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, nafcillin, oxacillin, cloxacillin, and dicloxacillin) at trace levels in muscle tissue. This method involves extraction of the penicillins with phosphate buffer pH 9 followed by cleanup and concentration on a C18 solid¯phase extraction column and reaction with benzoic anhydride at 50°C for 5 min and with 1,2,4-triazole and mercury(II) chloride solution pH 9 at 65°C for 10 min. The derivatized compounds are eluted on a C18 column with a mobile phase containing acetonitrile and phosphate buffer (pH 6; 0.1 mol/L) loaded with sodium thiosulfate and ion-pairing tetrabutylammonium hydrogenosulphate. The method detection limit is approximately 3-11 μg/kg and the limit of determination was evaluated down to 25 μg/kg in line with the criteria of the EU decision No. 93/256/EEC.

scholarly journals Haemocompatibility and ion exchange capability of nanocellulose polypyrrole membranes intended for blood purification

2012 ◽  
Vol 9 (73) ◽  
pp. 1943-1955 ◽  
Author(s):  
Natalia Ferraz ◽  
Daniel O. Carlsson ◽  
Jaan Hong ◽  
Rolf Larsson ◽  
Bengt Fellström ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Platelet Adhesion ◽  
Conductive Polymer ◽  
Exchange Capacity ◽  
The Novel ◽  
Isotonic Solution ◽  
Solution Ph ◽  
Heparin Coating ◽  
New Generation ◽  
Cellulose Composite

Composites of nanocellulose and the conductive polymer polypyrrole (PPy) are presented as candidates for a new generation of haemodialysis membranes. The composites may combine active ion exchange with passive ultrafiltration, and the large surface area (about 80 m 2 g −1 ) could potentially provide compact dialysers. Herein, the haemocompatibility of the novel membranes and the feasibility of effectively removing small uraemic toxins by potential-controlled ion exchange were studied. The thrombogenic properties of the composites were improved by applying a stable heparin coating. In terms of platelet adhesion and thrombin generation, the composites were comparable with haemocompatible polymer polysulphone, and regarding complement activation, the composites were more biocompatible than commercially available membranes. It was possible to extract phosphate and oxalate ions from solutions with physiological pH and the same tonicity as that of the blood. The exchange capacity of the materials was found to be 600 ± 26 and 706 ± 31 μmol g −1 in a 0.1 M solution (pH 7.4) and in an isotonic solution of phosphate, respectively. The corresponding values with oxalate were 523 ± 5 in a 0.1 M solution (pH 7.4) and 610 ± 1 μmol g −1 in an isotonic solution. The heparinized PPy–cellulose composite is consequently a promising haemodialysis material, with respect to both potential-controlled extraction of small uraemic toxins and haemocompatibility.

Interception of sediment-liberated phosphate in a surface aquatic system for eutrophication control

2019 ◽  
Vol 20 (1) ◽  
pp. 197-208
Author(s):  
Ge Gao ◽  
Shengjiong Yang ◽  
Huining Xu ◽  
Mawuli Dzakpasu ◽  
Pengkang Jin ◽  
...  
Keyword(s):  
Primary Source ◽  
Internal Loading ◽  
Aquatic System ◽  
Laboratory Scale ◽  
Aquatic Systems ◽  
The Novel ◽  
Solution Ph ◽  
Overlying Water ◽  
Eutrophication Control ◽  
Actual Application

Abstract Phosphorus internal loading from the sediment of a surface aquatic system is considered to be the primary source of phosphorus responsible for eutrophication. In this study, we propose a possible solution to intercept phosphorus liberated from sediment to overlying water by a membranous nano-barrier (MNB) with tunable capacity. The equilibrium could be attained within 2 h when the MNB interacted with phosphate-containing water. The intercepting capacity was almost unaffected when the solution pH was varied from 4 to 10. The laboratory-scale trial showed that the MNB could positively intercept phosphorus liberated from sediment when the MNB covered the sediment, and the MNB was easy to replace once it became phosphate saturated, making its actual application feasible. Generally, the novel MNB can be considered to be a possible pathway for eutrophication control in shallow surface aquatic systems and scenic water.

scholarly journals Chemical Modification of Bagasse-Based Mesoporous Carbons for Chromium(III) Ion Adsorption

2017 ◽  
Vol 15 (1_suppl) ◽  
pp. 52-61
Author(s):  
Haiwen Ma ◽  
Kunquan Li ◽  
Qiangfei Chai
Keyword(s):  
Adsorption Capacity ◽  
Ion Adsorption ◽  
Mesoporous Carbons ◽  
Solution Ph ◽  
High Efficient ◽  
Kinetic Rates ◽  
Key Factor ◽  
Pseudo Second Order ◽  
Xps Study ◽  
H3po4 Activation

Aims Modified bagasse-based mesoporous carbons were prepared for the efficient chromium(III) ion adsorption and removal from aqueous solutions. Methods Mesoporous carbons were prepared from bagasse with H3PO4 activation and subsequently oxidized with nitric acid and modified with ethylenediamine. Results The results showed that the modified carbon was rich in mesopores, oxygen and nitrogen-containing groups, and the Cr(III) adsorption capacity was greatly improved after modification, which was found to be higher than both pristine and oxidized carbons. The Cr(III) adsorption capacity on modified carbon was significantly influenced by the solution pH, and the optimum pH was 6 with the maximum Cr(III) adsorption capacity up to 24.61mg/g, which was almost 3 times higher than that for pristine carbon. Thermodynamic results manifested the adsorption was spontaneous and endothermic. Kinetic rates fitted the pseudo-second-order model very well. XPS study indicated the amino group was a key factor of the high efficient adsorption.

scholarly journals Synthesis and Binding Studies of a Novel Highly Selective Ag(I) Ligand

2020 ◽  
Author(s):  
Abiodun Aderibigbe ◽  
Andrew J. Clark
Keyword(s):  
Coordination Complexes ◽  
Low Grade ◽  
The Novel ◽  
Important Class ◽  
Tetrahedral Coordination ◽  
Binding Studies ◽  
Silver Recovery ◽  
Nmr Titration ◽  
Titration Data ◽  
Excellent Selectivity

Ligands bearing <i>S</i>- and <i>N</i>- donors are an important class of extractants with demonstrated efficiency and selectivity for Ag<sup>+</sup> extraction over metals with similar chemistries. However, the synthesis of some of these ligands can be complicated and low yielding. Here, we report the synthesis of a novel ligand - <i>N</i>-(2-((4-vinylbenzyl)thio)ethyl)acetamide, over two simple steps and in a good yield. The extractant was observed to demonstrate excellent selectivity for Ag<sup>+</sup>, extracting only Ag<sup>+</sup> from an aqueous solution also containing Cu<sup>2+</sup> and Pb<sup>2+</sup>. Moderate extraction efficiencies of 36 % for Ag<sup>+</sup> and 0% each for Cu<sup>2+</sup> and Pb<sup>2+</sup> were observed. From mass spectrometry and proton NMR titration data, the extractant was found to form both the 1:1 and 1:2 (Ag<sup>+</sup>:ligand) complexes with Ag<sup>+ </sup>indicating that ligand forms bent linear and tetrahedral coordination complexes with Ag<sup>+</sup>. Overall, the results indicate that the novel amide-based ligand is highly selective for Ag<sup>+</sup> removal from aqueous solutions containing Cu<sup>2+</sup> and Pb<sup>2+</sup>. These results indicate the ligand could be easily synthesized and applied for selective silver recovery from low grade ores.

scholarly journals Silver Recovery from the Oxidative Leaching Residue of Copper Anode Slime

1989 ◽  
Vol 30 (3) ◽  
pp. 165-174 ◽  
Author(s):  
Koichi Arai ◽  
Sumiko Sanuki ◽  
Norio Minami ◽  
Satoshi Sunada
Keyword(s):  
Anode Slime ◽  
Copper Anode ◽  
Silver Recovery ◽  
Copper Anode Slime ◽  
Oxidative Leaching ◽  
Leaching Residue

scholarly journals Heterogeneous Fenton Oxidation Using Magnesium Ferrite Nanoparticles for Ibuprofen Removal from Wastewater: Optimization and Kinetics Studies

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Andrei Ivanets ◽  
Vladimir Prozorovich ◽  
Marina Roshchina ◽  
Inga Grigoraviciute-Puroniene ◽  
Aleksej Zarkov ◽  
...  
Keyword(s):  
Fenton Reaction ◽  
Mesoporous Structure ◽  
Ferrite Nanoparticles ◽  
High Catalytic Activity ◽  
Magnesium Ferrite ◽  
Solution Ph ◽  
Morphological Studies ◽  
Oxidant Concentration ◽  
Iron Leaching ◽  
Heterogeneous Fenton Oxidation

In this study, the catalytic properties of Fenton-like catalyst based on magnesium ferrite nanoparticles for IBP degradation were examined. Structural and morphological studies showed the low crystallinity and mesoporous structure for the catalyst obtained via a glycine-nitrate method. The influences of catalyst dosage, oxidant concentration, and solution pH on the pollutant degradation were investigated. The pseudo-first-order model describes kinetic data, and under optimal condition (catalyst dose of 0.5 g L-1, H2O2 concentration of 20.0 mM, and pH of 8.0), apparent rate constant reached 0.091 min-1. It was shown that Fenton reaction was mainly induced by iron atoms on the catalyst surface, which is supported by very low iron leaching (up to 0.05 mg L-1) and high catalytic activity at neutral solution pH (6.0-8.0). It was found that the IBP mineralization onto magnesium ferrite catalyst was rapid and reached up to 98-100% within 40 min. Thus, prepared magnesium ferrite nanoparticles can be used as an effective Fenton-like catalyst for the IBP degradation from wastewater.

Fabrication and Water Treatment Application of High Efficient PbO2 Electrode

2017 ◽  
Vol 727 ◽  
pp. 821-829 ◽  
Author(s):  
Yi Nan Li ◽  
Xin Yu Zhuang ◽  
Hong Yu Li ◽  
Li Mei Ai ◽  
Yi Hu Wang ◽  
...  
Keyword(s):  
Surface Coating ◽  
Earth Element ◽  
Lattice Structure ◽  
Catalytic Performance ◽  
Material Surface ◽  
Catalytic Layer ◽  
The Novel ◽  
Life Test ◽  
High Efficient ◽  
Treatment Application

A novel and high efficient PbO2 electrode has been fabricated in the present study for refractory wastewater treatment. The traditional Ti plate is made into honeycomb by electronic corrosion to be used as electrode basement. The novel surface topography improves the specific surface area of the electrode material and enhances the adhesion of surface coating. SnO2-Sb layer is deposited between basement and PbO2 layer which reduces the thermal stress and improve electrode life. Rare earth element La is doping into PbO2 layer to improve the lattice structure and the catalytic performance. Finally, F ion is adding into the catalytic layer to improve the smoothness of the material surface. Characterized by SEM and XRD, results showed that the electrode prepared has novel surface morphology. Pollutants degradation results and electrode life test showed that the PbO2 electrode investigated in the present study has great advantage compared with traditional electrodes and has good application prospect.

scholarly journals Synthesis and Binding Studies of a Novel Highly Selective Ag(I) Ligand

2020 ◽  
Author(s):  
Abiodun Aderibigbe ◽  
Andrew J. Clark
Keyword(s):  
Coordination Complexes ◽  
Low Grade ◽  
The Novel ◽  
Important Class ◽  
Tetrahedral Coordination ◽  
Binding Studies ◽  
Silver Recovery ◽  
Nmr Titration ◽  
Titration Data ◽  
Excellent Selectivity

Ligands bearing <i>S</i>- and <i>N</i>- donors are an important class of extractants with demonstrated efficiency and selectivity for Ag<sup>+</sup> extraction over metals with similar chemistries. However, the synthesis of some of these ligands can be complicated and low yielding. Here, we report the synthesis of a novel ligand - <i>N</i>-(2-((4-vinylbenzyl)thio)ethyl)acetamide, over two simple steps and in a good yield. The extractant was observed to demonstrate excellent selectivity for Ag<sup>+</sup>, extracting only Ag<sup>+</sup> from an aqueous solution also containing Cu<sup>2+</sup> and Pb<sup>2+</sup>. Moderate extraction efficiencies of 36 % for Ag<sup>+</sup> and 0% each for Cu<sup>2+</sup> and Pb<sup>2+</sup> were observed. From mass spectrometry and proton NMR titration data, the extractant was found to form both the 1:1 and 1:2 (Ag<sup>+</sup>:ligand) complexes with Ag<sup>+ </sup>indicating that ligand forms bent linear and tetrahedral coordination complexes with Ag<sup>+</sup>. Overall, the results indicate that the novel amide-based ligand is highly selective for Ag<sup>+</sup> removal from aqueous solutions containing Cu<sup>2+</sup> and Pb<sup>2+</sup>. These results indicate the ligand could be easily synthesized and applied for selective silver recovery from low grade ores.

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