• Resources Recycling
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• v.31 no.6
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• pp.18-24
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• 2022

Dry reduction using natural gas was proposed to recover tin from waste tin oxide generated in a tin bath that was used for controlling the smoothness of architectural glass during production, and the reduction behavior was investigated. The utilized vertical natural gas dry reduction system is capable to process 4 L or 20 kg depending on input raw materials. The system was established by applying the upper intake and lower discharge method. The recovery rate was 97.2% at 800 ℃ and 4 sccm flow rate and increased with the amount of input gas. Hydrogen accounted for 23% of the discharge gas, showing a 16.6% hydrogen conversion rate. The reaction behavior of tin recovered via natural gas reduction provides basic data on the new waste resource reduction/recovery technology.

• Resources Recycling
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• v.24 no.2
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• pp.23-28
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• 2015

Most of the domestic need for tin rely on imports. In this work, a pyrometallurgical process was investigated to recover pure tin from the tin oxides in tin bath which results from the production of flat glass and LCD panel. From the results on the effect of reaction temperature, the highest recovery percentage of tin was obtained at $1350^{\circ}C$. The recovery percentage of tin was improved to 88% by employing the first and second smelting step. Electrorefining of the crude tin thus obtained led to pure tin with purity higher than 99.9%.

• Resources Recycling
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• v.27 no.6
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• pp.38-43
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• 2018

In this study, using electro-refining process and methane gas reduction, we performed studying the recovery of tin with high purity from waste tin oxide had used as a electrode rod of ceramic furnace which occurred during glass production process. We recovered the crude tin of 99% purity from a methane gas reduction process and controlled a little amount of impurities. When the electrolytic refining condition was a current density of $60A/dm^2$ and the sulfuric acid concentration of 0.75 mol, 96.8% of recovered tin (99.979% of purity) were recovered during the electrolytic refining. We confirmed that toxic impurities such as Pb, Sb included in electrode rod. could be controlled.

• Korean Journal of Materials Research
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• v.22 no.4
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• pp.174-179
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• 2012

In this study, we demonstrated a simple and eco-friendly method, including mechanical polishing and attrition milling processes, to recycle sputtered indium tin oxide targets to indium tin oxide nanopowders and targets for sputtered transparent conductive films. The utilized indium tin oxide target was first pulverized to a powder of sub- to a few- micrometer size by polishing using a diamond particle coated polishing wheel. The calcination of the crushed indium tin oxide powder was carried out at $1000^{\circ}C$ for 1 h, based on the thermal behavior of the indium tin oxide powder; then, the powders were downsized to nanometer size by attrition milling. The average particle size of the indium tin oxide nanopowder was decreased by increasing attrition milling time and was approximately 30 nm after attrition milling for 15 h. The morphology, chemical composition, and microstructure of the recycled indium tin oxide nanopowder were investigated by FE-SEM, EDX, and TEM. A fully dense indium tin oxide sintered specimen with 97.4% of relative density was fabricated using the recycled indium tin oxide nanopowders under atmospheric pressure at $1500^{\circ}C$ for 4 h. The microstructure, phase, and purity of the indium tin oxide target were examined by FE-SEM, XRD, and ICP-MS.