• 한국지구물리탐사학회:학술대회논문집
• /
• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
• /
• pp.642-647
• /
• 2003

Palladium is widely used for several applications and recovery of palladium from secondary sources becomes increasingly important since palladium is one of maldistributed platinum group metals. Electrochemical recovery of dense palladium metal sheet from Pd leaching solution is a simple and easily controlled method. The surface morphology of the recovered Pd metal was significantly affected by current density and temperature. Dense deposit morphology was in higher stress state regardless of preparation condition under $55^{\circ}C$. Rising temperature up to $70^{\circ}C$ had a stress releasing effect besides densification of Pd deposit.

• 한국자원리싸이클링학회:학술대회논문집
• /
• 한국자원리싸이클링학회 2005년도 제13회 산화철워크샵
• /
• pp.3-14
• /
• 2005

We Investigated minutely how the biosorption technology using algal biomass is opened in Canadian technology society. Making comparative study for relative technologies in views of overall unit operation cost, we could grasp next facts. - Algal biomass plays the competitive performance for various metals. - Algal biomass biosorbent is regenerated. - Reactor system is not and involved one. This means that algal biomass occupies the strong position as biosorbent. Especially, in North America, for the purpose of metal bearing wastewater treatment, 20 hundred million US dollars was appropriated a sum for the purchase of ion exchange resin. But it is only thirty million US dollars if algal biomass biosorbent is used on behalf of ion exchange resin. Furthermore, the expenses for same treatment can be cut down additively through metal recovery.

• 대한기계학회논문집A
• /
• 제27권4호
• /
• pp.515-523
• /
• 2003

Shape memory is physical phenomenon which a platically metal is restored to its original shape by a solid state phase change by heating. TiNi alloy the most effective material in the shape memory alloy(SMA). To study(measure) recovery stress of intelligent composite. Ti50-Ni50 shape memory matrix with prestrain SMA fiber. When SMA fiber of the intelligent composite is heated over austenite starting temperature(As) by electric heating. a recovery stress are generated. The recovery stress of the intelligent composite was measured by strain gage or photoelastic experiment. Measuring method of recovery stress by photoelastic experiment was developed in this research. It was certified that photoelastic experiment was more effective and more precise than strain gage method in the measurement of recovery stress.

• 한국환경과학회지
• /
• 제25권2호
• /
• pp.331-336
• /
• 2016

In this study the optimum conditions for recovery of valuable metal in Electric Arc Furnace Dusts were investigated. 2M of $H_2SO_4$, 1~5 of solid/liquid ratio, 0~180 min of leaching time has been established for leaching condition, and for electrowinning, each of Pt, C, Zn, Pb anode and Zn, Cu cathode was compared respectively at pH 2, 4 and 6. The result of elemental analysis of Zn crystal, a lagre quantity of Fe and H has been observed with Zn and other heavy metal, therefore, impurities removing process would be requir for enhancing purity of Zn. As the result, about 60% of Zn has been recovered under condition of 2 M of $H_2SO_4$, 1:2 of S/L ratio at 120 min, and Pt or Pb for anode, Zn for cathode has been shown the highest efficiency of electrowinning at pH 6.

• 한국표면공학회지
• /
• 제42권1호
• /
• pp.53-57
• /
• 2009

Recovery of heavy-metallic component from a waste solution of factory was undertaken by the solar cell electricity. The solution was obtained from an electrolytic etching process of 316L stainless steel. The electrolysis of the solution for recovery of heavy metallic components was made with platinum plated titanium mesh anode and copper plate cathode. Analysis for the solution and electro-winned materials were made by EDS, XRD and SEM. Iron, chromium, and sulfur components were recovered on the cathode from the solution. Result of EDS analysis for the electro-winned materials revealed that some metal oxide were contained in the recovered material. The recovered materials were expected to have metallic form only by the electrolysis, but metal compounds were contained because of weak solar cell power. Nickel and manganese component in the solution doesn't recovered by this electrolysis process, but they made a sludge with phosphoric acid in the solution.

• 한국군사과학기술학회지
• /
• 제17권4호
• /
• pp.413-421
• /
• 2014

Since the structural temperature of a flight vehicle flying at high speed rises rapidly due to aerodynamic heating, it is necessary for optimum structural design to obtain proper material properties at high temperature by taking into account of its operational environment. For a special alloy, analysis data on strength change due to exposure time to high temperature are very limited, and most of them are for an exposure time longer than 30 minutes for long term operations. In this study, base and weld metal samples of Ti-6Al-4V alloy had been prepared and high temperature tensile tests with induction heating were performed, and then high temperature strength characteristics and strength recovery characteristics through cooling have been analyzed. Pre-tests to determine maximum heating rate were performed, and response characteristics for temperature control were confirmed. As a result, high temperature tensile strength appeared to be lower than that of room temperature, but it was higher than that of high temperature of 30 minite exposure listed in MMPDS. In strength recovery through cooling Ti-6Al-4V alloy has shown higher recovery rate compared with other alloys.

• 자원리싸이클링
• /
• 제21권4호
• /
• pp.26-34
• /
• 2012

제품을 제조하는 대부분의 공정에서는 불량품이나 스크랩 등의 폐기물이 발생한다. 전기전자 제품을 생산하는 공정에서도 금속을 함유한 복합물질의 폐기물이 다량 발생하며, 이로부터 금속을 회수하는 것은 자원재활용의 측면 뿐 아니라 매립 등의 처리에 대한 환경부담을 줄이는 효과가 있다. 이 논문에서는 전기전자 제품을 제조하는 공정에서 발생하는 불량품을 포함한 폐기물로부터 금속을 회수하는 기술에 대하여 1975년부터 2011년까지 공개/등록된 미국, 일본, 유럽, 한국의 특허와 SCI급 논문을 조사하였다. 키워드를 이용하여 조사하였고 필터링 하여 특허와 논문을 수집하여 연도별, 국가별, 기관별, 기술별로 분석하였다. 분석결과, 특허의 경우는 한국, 일본, 미국 순으로 많이 제출하였고 논문의 경우에는 대만, 미국 순이었다.

• 한국산학기술학회논문지
• /
• 제16권1호
• /
• pp.906-913
• /
• 2015

알루미나를 생산하는 Bayer 공정에서 발생하는 레드머드는 환경과 인간에게 심각한 위험요인이 되고 있어, 알루미늄 산업에서 레드머드의 발생량을 줄이거나 또는 재활용 하는 것은 매우 시급한 문제이다. 본 연구에서는 초음파 강도, 반응온도, 반응시간 및 산성용액 농도 등 4가지 변수가 레드머드 내의 철과 알루미늄의 침출에 미치는 영향에 대해 연구하였다. 레드머드로부터 금속 성분의 용출에 미치는 가장 중요한 변수는 초음파 강도와 반응온도로 나타났다. 초음파를 조사할 경우, 철과 알루미늄의 회수율은 초음파를 조사하지 않은 경우보다 각각 1.72배와 1.28배 정도 증가하는 것으로 나타났다. 본 연구결과, 알루미나로부터 금속성분을 회수하기 위한 적정 조업조건은 초음파 강도 150 W, 황산 용액의 농도 4-6N, 반응온도 $70^{\circ}C$, 반응시간 2시간 등이었다.

• 분석과학
• /
• 제8권4호
• /
• pp.561-568
• /
• 1995

Two methods, precipitation and ultrafiltration, were applied in order to recover platinum group metals(PGM) by complexing them with water-soluble polyelectrolytes, e.g., polyethyleneimine [PEl], poly(2-vinylpyridine) [2-PVP], poly (4-vinylpyridine) [4-PVP], and poly (styrene sulfonic acid) [PSSA]. In the precipitation method, the PGM-polyelectrolyte complex that was formed by mixing first with polybase, e.g.,4-PVP at pH 1 was precipitated by further mixing with polyacid, e.g., PSSA. However, the recovery of PGM obtained by this method was not quantitative(less than 70%). The "sandwiching" binding between the metal anions and two polyelectrolytes was examined by X-ray photoelectron spectroscopy(XPS). The XPS studies indicated that the PGM atom was bound with the acdic and basic polyelectrolyte via its oxygen and nitrogen atom, respectively. The recovery of PGM using polyelectrolyte was further studied by ultrafiltration methods as follows : The PGM ions, eomplexed at pH 1 with polyelectrolyte, allowed the applicntion of membrane filtration by virtue of the great differences in molecular weights between PGM and other low molecular weight species. By applying this method, Pd and Pt (ca. $10^{-4}M$) were selectively separated almost quantitatively from coexisting metal ions, e.g., $Cu^{2+}$ and $Ni^{2+}$. The EPR spectra and viscosity measurements indicated that these polyelectrlytes were not bound to $Cu^{2+}$ and $Ni^{2+}$ ions at this pH, which provided the basis for selective separation of PGM(Pd, Pt and Rh) from these coexisting ions.

• 자원리싸이클링
• /
• 제22권6호
• /
• pp.73-80
• /
• 2013

해양광물자원은 크게 해저면에 부존되어 있는 해저광물자원과 해수 중에 녹아 있는 해수광물자원으로 대별된다. 해수에는 막대한 양의 유용광물이 녹아 있어 회수기술 개발이 완료되면 상업화 가능성이 큰 것으로 알려져 있다. 21세기에 들어 육상금속자원의 저품위화 및 매장량 고갈에 따라 자원 보유국들이 자원을 무기화 하는 경향이 심화되고 있다. 따라서 대부분의 금속자원을 수입에 의존하는 우리나라는 삼면이 바다인 지리적 특성을 살려 해수로부터 희유금속 회수기술 개발에 적극적으로 나설 필요가 있다. 본 연구에서 해수로부터 희유금속 회수관련 논문분석 결과, 미국이 495편의 논문을 게재하여 양적 질적으로 가장 우수한 것으로 나타났다. 연구기관별로 보면 Chinese Acad. Sci.가 152편의 논문을 게재하여 양적으로 많은 연구가 이루어졌으며, 31편의 논문을 게재한 Univ. Oxford는 질적으로 가장 우수한 것으로 나타났다.