• Resources Recycling
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• v.25 no.4
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• pp.68-79
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• 2016

Titanium is the ninth most abundant element in the Earth's crust. It is also the forth most abundant structural metal after aluminum, iron and magnesium. Titanium is conventionally produced by the Kroll process. New processes to produce metallic titanium have been currently developed by many researchers in the world. In this study, the existing technologies, including both commercial and developmental processes, categorized into three groups: those by metallothermic reduction of $TiCl_4$ and $TiO_2$, those by electrolytic reduction of $TiO_2$ and hydrogen reduction of Ti compounds. Their mechanisms for reduction and their features are summarized and discussed in the view of industrial application.

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.11a
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• pp.43-43
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• 2001

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2005.11a
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• pp.80-81
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• 2005

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.11a
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• pp.53-54
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• 2002

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.45.1-45
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• 2002

• Resources Recycling
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• v.16 no.2 s.76
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• pp.3-11
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• 2007

It is to review the current status of magnesium smelting. Raw materials for magnesium source, worldwide production and producers of metallic magnesium, Korean magnesium markets and some important extraction technologies were reviewed. The magnesium extraction technologies were described according to the two major reduction methods: the fused salt electrolysis and the thermal reduction method. Also, the research on the extraction of magnesium from magnesite which has been being carried out at KIGAM was briefly introduced with discussing the related topics on the recycling of the chlorine and the hydrogen chloride gas used in the process.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.145-145
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• 2013

저가 공정으로 진행되는 전기 방사 기법을 이용하여 태양전지용 구리 섬유를 제작하였다. 전기 방사 용액은 PVP, 에탄올, 염화 구리의 혼합액을 사용하였고, 금속염의 농도와 인가전압 변화에 따라 다양한 직경의 섬유가 제작되었다. 또한, 무질서 하게 방사되는 섬유의 배열 제어를 위해 컬렉터 형상을 변화하였다. 컬렉터에 형성된 고분자-구리 복합섬유를 채취한 후 열처리와 환원 처리를 통하여 구리 섬유를 얻었다. 환원된 금속 섬유는 scanning electron scope(SEM)을 통해 형상을 관찰하였으며, 4단자법으로 섬유의 전기적 특성에 관하여 알아보았다.

• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.372-381
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• 2015

The effect of preparation method on the catalytic activities of the $Ni/Al_2O_3$ catalysts on steam reforming of ethylene glycol was investigated. The catalysts were prepared with various preparation methods such as an incipient wetness impregnation, wet impregnation, and coprecipitation method. In the case of coprecipitation method, various precipitants such as KOH, $K_2CO_3$, and $NH_4OH$ were compared. The prepared catalysts were characterized by using $N_2$ physisorption, inductively coupled plasma-atomic emission spectroscopy, X-ray diffraction, temperatureprogrammed reduction, pulsed $H_2$ chemisorption, temperature-programmed oxidation, scanning electron microscopy, and thermogravimetric analysis. Among the catalysts reduced at 773 K, the $Ni/Al_2O_3$ catalyst prepared by a coprecipitation with KOH or $K_2CO_3$ as precipitants showed the best catalytic performance. The preparation method affected the particle size of Ni, reducibility of nickel oxides, catalytic performance (activity and stability), and types of coke formed during the reaction. The $Ni/Al_2O_3$ catalyst prepared by a coprecipitation with KOH showed the increasing catalytic activity with an increase in the reduction temperature from 773 to 1173 K because of an increase in the reduction degree of Ni oxide species even though the particle size of Ni increased with increasing reduction temperature.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2005.04a
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• pp.33-34
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• 2005

• Resources Recycling
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• v.21 no.6
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• pp.32-38
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• 2012

In this study, direct reduction of $ZrO_2$ using liquid calcium was investigated. The influence of molar ratio of Ca and $ZrO_2$, reaction time and temperature on the reduction behavior of $ZrO_2$ was studied. Experiments were conducted in a closed stainless steel chamber under Ar atmosphere during 5 to 60 minutes. Most of the $ZrO_2$ was reduced to Zr in 5 minutes at 1223 K and 3 Ca/$ZrO_2$ molar ratio. The minimum oxygen content in reduced metal Zr was obtained about 0.66 wt% at 1373 K after 30 minutes and 4 Ca/$ZrO_2$ molar ratio. The morphology of zirconium powder obtained was highly affected by the reaction temperature and reaction time.