Recovery of valuable metals from mining and mineral processing waste

Ammonia-thiosulfate-copper leaching, aided by a direct current electrochemical impact, is proposed to extract gold (Au), silver (Ag) and copper (Cu) from old flotation tailings mixed with waste rock. Over 80 % of Au available in the waste material and over 75 % of Cu and Ag were extracted into the pregnant leach solution (PLS) at room temperature. Electrowinning from that PLS recovered around 92 % of Au and Cu, and about 87 % of Ag in the cathode deposit that is suitable for further metallurgical refining. The results are better, compared to leaching in the same system but without electrochemical impact and at air addition. The proposed direct current aided method is promising and more environmentally friendly compared to cyanide and even to sodium thiosulfate leaching.

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Green-Synthesized Phosphorescent Carbon Dot Composite for Multilevel Anti-Counterfeiting

Nanoscale Advances ◽

10.1039/d1na00252j ◽

2021 ◽

Author(s):

wenjie Jiang ◽

Lan Liu ◽

Yueyue Wu ◽

Peng Zhang ◽

Feiyang Li ◽

...

Keyword(s):

Room Temperature ◽

Environmentally Friendly ◽

Carbon Dot

Room temperature phosphorescent (RTP) materials are rising and gaining considerable attention due to their special photo capture-release ability. Herein, a kind of environmentally friendly RTP C composite was devised by...

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Investigation an environmentally friendly method under magnetic field as a green solvent for the synthesis of brookite phase nanoparticles at room temperature

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-021-05889-4 ◽

2021 ◽

Author(s):

Yahya Absalan ◽

Mostafa Gholizadeh ◽

Vladimir V. Kopylov ◽

Leonid A. Butusov ◽

Valiolah Bagherzadeh ◽

...

Keyword(s):

Magnetic Field ◽

Room Temperature ◽

Environmentally Friendly ◽

Green Solvent ◽

Environmentally Friendly Method ◽

Brookite Phase

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Morphology Evolution and Luminescence Properties of YF3: Sm Nano-/Microcrystals

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.112 ◽

2012 ◽

Vol 463-464 ◽

pp. 112-118

Author(s):

Feng Tao ◽

Geng Zhu ◽

Zhi Jun Wang ◽

Feng Pan ◽

Yu Feng Sun ◽

...

Keyword(s):

Hydrothermal Method ◽

Growth Mechanism ◽

Room Temperature ◽

Red Light ◽

Environmentally Friendly ◽

Morphology Evolution ◽

Flat Panel Display ◽

Flat Panel ◽

Display Devices ◽

Potential Applications

Abstract. Recently, there has been increasting interest in the doping of nano-/microcrystal hosts with Sm3+. However, very few examples of Sm3+doped YF3-based nanophosphors have been reported. In this paper, a variety of uniform YF3:Sm nano-/microcrystals have been successfully prepared by a facile, effective, and environmentally friendly hydrothermal method. The morphology evolution process has been investigated by quenching the reaction at different time. Based on the results, a possible growth mechanism is presented in detail. The as-obtained YF3:Sm nano-/microcrystals show strong yellow and red light emissions under room temperature, which is quite different from those reported previously and might find potential applications in fields such as light phosphor powers and advanced flat panel display devices.

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CONCEPTS OF ELECTRONICALLY-CONTROLLED ELECTROMECHANICAL/MECHANOELECTRICAL STEER-, AUTODRIVE- AND AUTOABSORBABLE WHEELS FOR ENVIRONMENTALLY-FRIENDLY TRI-MODE SUPERCARS

Journal of Circuits System and Computers ◽

10.1142/s0218126694000296 ◽

1994 ◽

Vol 04 (04) ◽

pp. 501-516 ◽

Cited By ~ 8

Author(s):

BOGDAN T. FIJALKOWSKI ◽

JAN W. KROSNICKI

Keyword(s):

Direct Current ◽

Integrated Circuit ◽

Environmentally Friendly ◽

Alternating Current ◽

Switching Frequency ◽

Neuro Fuzzy ◽

Interior Permanent Magnet ◽

Application Specific Integrated Circuit ◽

Computer Processor ◽

Application Specific

Concepts of the electronically-controlled electromechanical/mechanoelectrical Steer-, Autodrive- and Autoabsorbable Wheels (SA2W) with their brushless Alternating Current-to-Alternating Current (AC-AC), Alternating Current-to-Direct Current-Alternating Current (AC-DC-AC) and/or Direct Current-to-Alternating Current (DC-AC)/Alternating Current-to-Direct Current (AC-DC) macroelectronic converter commutator (macro-commutator) wheel-hub motors/generators with the Application Specific Integrated Matrixer (ASIM) macroelectronic converter commutators (ASIM macrocommutators) and Application Specific Integrated Circuit (ASIC) microelectronic Neuro-Fuzzy (NF) computer (processor) controllers (ASIC NF microcontrollers) for environmentally-friendly tri-mode supercars (advanced ultralight hybrids) have been conceived by the first author and designed by both authors with the Cracow University of Technology’s Automotive Mechatronics Research and Development (R&D) Team. These electromechanical/mechanoelectrical wheel-hub motors/generators, respectively, for instance, can be composed of the outer rotor with the Interior Permanent Magnet (IPM) poles and the inner stator that has the three-phase armature winding. The macroelectronic converter commutator establishes the AC-AC cycloconverter, AC-DC rectifier-DC-AC inverter and/or DC-AC inverter/AC-DC rectifier ASIM macrocommutator. The microelectronic NF computer (processor) controller establishes the ASIC microcomputer-based NF microcontroller. By adopting continuous semiconductor bipolar electrical valves in the high-power ASIM, it has been able to increase the commutation (switching) frequency and reduce harmonic losses of the electromechanical/mechanoelectrical wheel-hub motors/generators, respectively.

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Environmentally friendly and facile synthesis of Rh nanoparticles at room temperature by alkaline ethanol solution and their application for ethanol electrooxidation

RSC Advances ◽

10.1039/c6ra26591j ◽

2017 ◽

Vol 7 (6) ◽

pp. 3161-3169 ◽

Cited By ~ 4

Author(s):

Fuhai Li ◽

Hanqin Weng ◽

Yun Shang ◽

Zuoming Ding ◽

Zheng Yang ◽

...

Keyword(s):

Room Temperature ◽

Environmentally Friendly ◽

Ethanol Solution ◽

Ethanol Electrooxidation ◽

Synthetic Route ◽

Facile Synthesis

A facile, fact and green synthetic route was developed to prepare Rh nanoparticles at room temperature.

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Mitigating the Antimicrobial Activities of Selected Organic Acids and Commercial Sanitizers with Various Neutralizing Agents

Journal of Food Protection ◽

10.4315/0362-028x.jfp-10-447 ◽

2011 ◽

Vol 74 (5) ◽

pp. 820-825 ◽

Cited By ~ 7

Author(s):

YOEN JU PARK ◽

JINRU CHEN

Keyword(s):

Escherichia Coli ◽

Acetic Acid ◽

Lactic Acid ◽

Organic Acids ◽

Shiga Toxin ◽

Room Temperature ◽

Sodium Thiosulfate ◽

Antimicrobial Activities ◽

Phosphate Buffered Saline ◽

Lactic Acids

This study was conducted to evaluate the abilities of five neutralizing agents, Dey-Engley (DE) neutralizing broth (single or double strength), morpholinepropanesulfonic acid (MOPS) buffer, phosphate-buffered saline (PBS), and sodium thiosulfate buffer, in mitigating the activities of acetic or lactic acid (2%) and an alkaline or acidic sanitizer (a manufacturer-recommended concentration) againt the cells of Shiga toxin–producing Escherichia coli (STEC; n = 9). To evaluate the possible toxicity of the neutralizing agents to the STEC cells, each STEC strain was exposed to each of the neutralizing agents at room temperature for 10 min. Neutralizing efficacy was evaluated by placing each STEC strain in a mixture of sanitizer and neutralizer under the same conditions. The neutralizing agents had no detectable toxic effect on the STEC strains. PBS was least effective for neutralizing the activity of selected organic acids and sanitizers. Single-strength DE and sodium thiosulfate neutralized the activity of both acetic and lactic acids. MOPS buffer neutralized the activity of acetic acid and lactic acid against six and five STEC strains, respectively. All neutralizing agents, except double-strength DE broth, had a limited neutralizing effect on the activity of the commercial sanitizers used in the study. The double-strength DE broth effectively neutralized the activity of the two commercial sanitizers with no detectable toxic effects on STEC cells.

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