Adaptive process for improving leaching efficiency of germanium from secondary zinc oxide

Abstract Adaptive process was used to treat germanium-containing secondary zinc oxide. The leaching parameters were determined by batch experiment, and continuous experiment was conducted and the stability of the process was verified. The leaching efficiency of Zn and Ge in the batch experiments were 92.51 and 90.67%, respectively, while the leaching efficiencies of Zn and Ge in the continuous experiment were 93.53 and 88.47%, respectively. In the neutralization process, the Fe3+ concentration in the neutralized solution is within 0.025 g/L. The Fe2+in the leaching solution increased gradually, as the neutralized residue was returned to the leaching process, the Zn in leaching residue reduce and the leaching efficiency of Zn increased. The residue mainly contained zinc sulfide and lead sulfate, with some fluffy structures on the surface. The process is promising for industrial application from indicators, economy, and applicability.

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Influence of additives on suspension structure

Advanced technologies ◽

10.5937/savteh2101037s ◽

2021 ◽

Vol 10 (1) ◽

pp. 37-40

Author(s):

Vesna Savić ◽

Milica Martinović ◽

Ivana Nešić ◽

Jelena Živković ◽

Ivana Gajić

Keyword(s):

Zinc Oxide ◽

The Other ◽

Stability Tests ◽

Polysorbate 20 ◽

The Stability ◽

Carbomer Gel ◽

Suspension Structure ◽

Insight Into ◽

Study Offer ◽

Measured Hardness

The aim of this study was to compare the stability and texture of three zinc oxide suspensions with different additives. Suspension 1 was made as official magistral formulation Suspensio album 7.5% from Formulae magistrales 2008. Suspension 2 was prepared when 1% carbomer gel was added to suspension 1 and suspension 3 was prepared when polysorbate 20 was added to suspension 2. After stability tests, texture analysis was performed on all suspensions. Following parameters were measured: hardness cycle 1, hardness cycle 2, cohesiveness, adhesiveness, resilience and springiness. The study showed that suspension 3 had the lowest value of hardness, and therefore the best spreadability. Also, suspension 3 was the least sticky of all three, since it was characterized with the lowest adhesiveness. Further, suspension 3 was the most cohesive and is predicted to withstand the stress during packing and use longer than others. On the other hand, the highest values of resilience and springiness were detected for suspension 1, while the lowest was related to suspension 2. Therefore, the best textural characteristics were assigned to suspension 3. This result is in accordance with the results of performed stability tests. The results of our study offer insight into potential improvements of the current magistral formulation Suspensio album 7.5%.

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Study the Effect of Gum Arabic and Triton X-100 on Stability and Thermal Conductivity of ZnO/ethylene glycol Nanofluids

Revista de Chimie ◽

10.37358/rc.21.1.8400 ◽

2021 ◽

Vol 72 (1) ◽

pp. 18-24

Author(s):

Noor Sabeeh Majeed ◽

Hussein A. Alabdly ◽

Hussam Nadum Abdalraheem Al Ani ◽

Dumitru Pascu ◽

Aurelia Cristina Nechifor

Keyword(s):

Thermal Conductivity ◽

Zinc Oxide ◽

Zeta Potential ◽

Ethylene Glycol ◽

Base Fluid ◽

Thermal Conductivity Coefficient ◽

Uv Spectroscopy ◽

Gum Arabic ◽

The Stability ◽

Triton X

Stability of nanofluids is one of the most important factors to ensure the most benefit of the properties of nanoparticles. Zinc oxide was used in the research with concentration between (0.2-1) wt. % with ethylene glycol base fluid. The stability of ZnO nanofluid was enhanced by adding two types of surfactants Tx-100 and Gum Arabic with concentration of (0.1-0.5) vol. % to stabilize the ZnO nanoparticles in the base fluid. The results showed that the Gum Arabic surfactant led to more stable fluid than that of Tx-100; this was shown from zeta potential and UV spectroscopy measurements. The thermal conductivity coefficient was also measured, and the results showed that the thermal conductivity increased with adding surfactant than without using a stabilizer.

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Influence of ambient humidity on the stability of negative bias illumination for amorphous indium gallium zinc oxide thin film transistors

Chinese Journal of Liquid Crystals and Displays ◽

10.37188/cjlcd.2020-0305 ◽

2021 ◽

Vol 36 (5) ◽

pp. 649-655

Author(s):

Guo-feng FENG ◽

◽

Wen ZHANG ◽

Cheng-yuan DONG

Keyword(s):

Thin Film ◽

Zinc Oxide ◽

Thin Film Transistors ◽

Oxide Thin Film ◽

Negative Bias ◽

Indium Gallium Zinc Oxide ◽

Zinc Oxide Thin Film ◽

Ambient Humidity ◽

Indium Gallium ◽

The Stability

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Enhancing the stability and water resistance of CsPbBr3 perovskite nanocrystals by using tetrafluoride and zinc oxide as protective capsules

Journal of Materials Science ◽

10.1007/s10853-020-04554-1 ◽

2020 ◽

Vol 55 (23) ◽

pp. 9739-9747

Author(s):

Pengjie Song ◽

Bo Qiao ◽

Dandan Song ◽

Jingyue Cao ◽

Zhaohui Shen ◽

...

Keyword(s):

Zinc Oxide ◽

Water Resistance ◽

Perovskite Nanocrystals ◽

The Stability

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Preparation of Calcium Stannate from Lead Refining Dross by Roast–Leach–Precipitation Process

Minerals ◽

10.3390/min9050283 ◽

2019 ◽

Vol 9 (5) ◽

pp. 283 ◽

Cited By ~ 2

Author(s):

Dixiu Wu ◽

Junwei Han ◽

Wei Liu ◽

Fen Jiao ◽

Wenqing Qin

Keyword(s):

Precipitation Process ◽

Lead Smelter ◽

Solid Ratio ◽

Lead Refining ◽

Average Grain Size ◽

Naoh Solution ◽

Leaching Solution ◽

Leaching Parameters ◽

Optimized Conditions ◽

Calcium Stannate

Lead refining dross containing plenty of tin and other heavy metals, such as lead and antimony, is considered a hazardous waste generated in large quantities in lead smelter plants. In this study, calcium stannate was synthesized from lead refining dross using sodium carbonate roasting and alkaline leaching followed by precipitation with CaO. The effect of roasting and leaching parameters on the extraction efficiency of tin was investigated. The leaching efficiency of tin reached 94% under the optimized conditions: roasting with 60% Na2CO3 at 1000 °C for 45 min, and leaching using 2 mol/L NaOH solution for 90 min at 85 °C and 8 cm3/g liquid/solid ratio. Furthermore, more than 99% of tin in the leaching solution was precipitated using CaO. Finally, XRD, SEM, and ICP-OES analyses indicated that the final CaSnO3 product had a purity of 95.75% and its average grain size was smaller than 5 μm. The results indicated that the developed method is feasible to produce calcium stannate from lead refining dross.

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Recovery and Then Individual Separation of Platinum, Palladium, and Rhodium from Spent Car Catalytic Converters Using Hydrometallurgical Technique followed by Successive Precipitation Methods

Journal of Chemistry ◽

10.1155/2019/2318157 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Ahmed M. Yousif

Keyword(s):

Contact Time ◽

Catalytic Converter ◽

Economic Value ◽

Hydrogen Atmosphere ◽

Catalytic Converters ◽

Batch Experiments ◽

Experimental Conditions ◽

Leaching Process ◽

Manufactured Products ◽

Leaching Solution

Recovery of PGMs (especially rhodium, platinum, and palladium) from different spent manufactured products (like catalytic converters) is considered as an important task as they are rarely found in nature, and they possess high economic value. In this work, the honeycomb of a car catalytic converter was primarily processed by crushing, grinding, and then treating in a hydrogen atmosphere. In order to establish an economic and ecofriendly method for the recovery of studied PGMs, different experimental conditions of changing HCl/H2O2 (as a leaching solution) ratio, temperature, and contact time were studied through batch experiments to obtain the optimum leaching conditions. The use of 0.8 vol% H2O2 and 9.0 M HCl mixture at 60°C for a contact time of 2.5 hours during the leaching process may be considered as the best conditions to be followed to save chemicals, energy, and time (about 86%, 96%, and 98% of Rh, Pt, and Pd were recovered, respectively). Individual separation of PGM ions from each other using precipitation technique from their leaching liquor was performed where % purity values of 99.5, 99.3, and 95.5 were obtained for Pt, Pd, and Rh, respectively.

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Experimental Study on Sulfuric Acid Leaching Behavior of Chromite with Different Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.361-363.628 ◽

2011 ◽

Vol 361-363 ◽

pp. 628-631 ◽

Cited By ~ 4

Author(s):

Cheng Jun Liu ◽

Jie Qi ◽

Mao Fa Jiang

Keyword(s):

Sulfuric Acid ◽

Acid Leaching ◽

Raw Material ◽

Leaching Rate ◽

Sulfuric Acid Leaching ◽

Leaching Process ◽

Pollution Problem ◽

Environmental Pollution Problem ◽

Leaching Solution ◽

Leaching Residue

Utilizing Pakistan chromite as raw material, the rapid leaching of chromium and iron could be realized by the sulfuric acid leaching process on the condition of atmospheric pressure and the addition of oxidant A. And the leaching rate of chromium and iron would be 98.5% and 71.9%, respectively. The sulfuric acid leaching processes with different temperature were systematically studied by chemical analysis and phase analysis. The results showed that, with the increase of reaction temperature, the leaching rate of chromium would increase gradually, but the leaching rate of iron increased at first and then decreases and reached its maximum at 140°C. When the temperature > 160°C, the phases of the leaching residue were magnesium iron silicate and a few of silica, no chromohercynite, chrompicotite and magnesioferrite existed in the chromite. The leaching solution of sulfuric acid leaching process could be used for preparing the basic chrome sulfate, and there is no Cr6+ in the leaching residue and solution. The results would provide theoretical guidance for solving environmental pollution problem of Cr6+ in traditional chromate production process.

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Influence of Accelerator Residues on Age Resistance of Vulcanizates

Rubber Chemistry and Technology ◽

10.5254/1.3542168 ◽

1960 ◽

Vol 33 (2) ◽

pp. 490-501

Author(s):

Z. T. Ossefort

Keyword(s):

Zinc Oxide ◽

Natural Rubber ◽

Network Structure ◽

Dual Process ◽

Curing Process ◽

Active Inhibitor ◽

The Stability ◽

Prime Function ◽

Better Than

Abstract It has been shown that the age resistance of elastomeric vulcanizates is influenced to a very marked degree by residues formed in situ in the vulcanizate during the curing process. By a dual process of removal of these residues and incorporation of selected ingredients subsequent to vulcanization, it has been shown that age resistance (as measured by accelerated oven-aging tests at 212° F) in rubbers cured by sulfur and/or sulfur bearing accelerators, is a prime function of these residues and nearly independent of the stability of the network structure. An extremely active inhibitor is formed in situ during vulcanization of SBR and natural rubber using thiuram accelerators. This inhibitor can be used to “reinhibit” acetone-extracted accelerator-cured rubber. When added to sulfur/accelerator, peroxide, or radiation-cured vulcanizates, it improves their age resistance, but only in the case of the sulfur/accelerator cured rubber is this improvement better than with conventional inhibitors. This leads to the conclusion that the efficiency with which an inhibitor protects a vulcanizate varies widely, and conversely it appears that certain types of network structures are more readily protected or that certain inhibitors can function more efficiently in the protection of certain structures than others. In the case of natural rubber cured with TMTD (zinc oxide present), the bulk of the accelerator residue is ZnDMDC, and this residue has been shown to function as a very efficient antioxidant when incorporated into acetone-extracted, accelerator-cured vulcanizate. It is no more effective than conventional inhibitors, however, when incorporated into an acetone-extracted, sulfur/accelerator-cured vulcanizate. Finally, it has been shown that acetone extraction of the various vulcanizates may lead to improvement or worsening of their age resistance, depending upon the nature of the residues resulting from the curing process.

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