• 공업화학
• /
• 제9권1호
• /
• pp.115-120
• /
• 1998

메타세시스에 높은 활성을 나타내는 고분산 레늄촉매을 제조하기 위한 레늄카보닐 침착의 표면화학 및 활성점 생성에 관하여 연구하였다. 알루미나는 773K(PDA)와 1223K(DA)에서 각각 처리하여 담체로 사용하였고, 메타세시스 활성은 순수한 프로펜을 사용하여 상압하의 298K에서 조사하였다. PDA상의 레늄 산화가는 상당히 높았으나, DA에서는 저산화가의 레늄으로 담지되어 있었다. 제조한 Re/DA촉매를 고온에서 열분해시킨 다음 저온에서 산소로 처리하면 메타세시스 활성이 나타났고, 그 활성은 극히 낮은 담지율에서도 Re/PDA이나 통상의 $Re_2O_7/Al_2O_3$촉매에 비해 높은 활성을 보여, 레늄 카보닐을 출발물질로 하고 DA를 사용하는 것이 효과적이었다. 열분해하여 얻은 Re/DA촉매상의 레늄이온은 알루미나의 산소원자 2개와 결합하여 2가를 가지고, 산소처리에 의하여 4가만큼 증가한 6가의 레늄이온이 되며, 메타세시스는 그 6가이온에 의해 생성된 카르벤착체를 통하여 진행됨을 알았다.

• Bulletin of the Korean Chemical Society
• /
• 제25권1호
• /
• pp.79-84
• /
• 2004

The existing technological schemes for processing rhenium-containing raw materials involve the recovery of Re from solutions, which can be effectively achieved by anion exchange method. The application of anion exchange also allows to study rhenium state in aqueous solutions and to develop analytical control methods. The present work is focused on investigation of ion exchange equilibrium in the analytical system Re(VII)-HCl-$SnCl_2$-KSCN-anion exchanger by means of sorption-desorption method as well as by electron, IR- and diffuse reflection spectroscopy. It was shown that rhenium can be quantitatively recovered from this system. It is proposed to use the sorption-spectroscopic method for Re(VII) determination in aqueous solutions. The calibration curve is linear in the concentration range of 0.5-20.0 mg/L (sample volume is 25.0 mL) and the detection limit is 0.05 mg/L. The presence of Mo(VI), Cu(II), Fe(II, III), Ni(II), Zn(II) as well as $K^+,\;Na^+$ do not hinder the solid-phase determination of rhenium. Rhenium (VII) determination by diffuse reflection spectroscopy was carried out in model solutions as well as in samples of river-derived water and in solutions obtained after the dissolution of spent catalysts.

• 자원리싸이클링
• /
• 제18권5호
• /
• pp.37-43
• /
• 2009

휘수연석으로부터 몰리브덴을 생산하는 과정 중 부산물로서 산출되는 레늄은 고강도, 고효을 부품을 만들기 위한 원료로 사용되며, 최근 첨단 산업에서 레늄의 수요가 급격히 상승하고 있는 실정이다. 본 연구에서는 휘수연석 정광을 배소할 때 발생된 분진을 대상으로, NaOH 농도, 침출온도, 반응시간에 대한 영향을 고려하여 레늄 및 몰리브덴의 침출거동을 조사하였다. NaOH $4\;mol{\cdot}L^{-1}$, 고액비 $100\;g{\cdot}L^{-1}$, 온도 $80^{\circ}C$, 교반속도 250 rpm, 반응시간 2시간의 침출조건에서 레늄 및 몰리브덴의 침출율은 각각 86.1%, 88.6%였다.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 1998년도 추계학술발표회요약집
• /
• pp.301-301
• /
• 1998

• Bulletin of the Korean Chemical Society
• /
• 제24권4호
• /
• pp.504-506
• /
• 2003

• Bulletin of the Korean Chemical Society
• /
• 제27권6호
• /
• pp.939-940
• /
• 2006

• Mass Spectrometry Letters
• /
• 제1권1호
• /
• pp.17-20
• /
• 2010

As background significantly affects measurement accuracy and a detection limit in determination of the trace amounts of uranium, it is necessary to minimize the impurities in the filaments used for thermal ionization mass spectrometry (TIMS). We have varied the degassing condition such as the heating currents and duration times to reduce the backgrounds from the filaments prepared with zone-refined rhenium tape. The most efficient degassing condition of the heating current and the duration time was determined as 3.5 A and 60 min, respectively. The TIMS measurement combined with the isotope dilution mass spectrometry (IDMS) technique showed that the uranium backgrounds were determined to be in a few fg level from blank rhenium filaments. The background minimized filaments were utilized to measure the uranium isotope ratios of a U030 (NIST) standard sample. The excellent agreement of the measurement with the certified isotope ratios showed that the degassing procedure optimized in this study efficiently reduced the impurity signals of uranium from blank rhenium filaments to a negligible level.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
• /
• pp.1650-1653
• /
• 2007

We demonstrate fluorescent green organic lightemitting diodes employing a rhenium oxide ($ReO_3$)-doped N,N-diphenyl-N,N'-bis(1,1'-biphenyl)-4,4'-diamine (NPB) hole transporting layer (HTL). The devices exhibit significantly reduced driving voltages as well as prolonged lifetime. Details of $ReO_3$ doping effects are described in terms of charge transfer complex and stabilization of HTL morphology.

• Bulletin of the Korean Chemical Society
• /
• 제27권5호
• /
• pp.635-636
• /
• 2006

• Bulletin of the Korean Chemical Society
• /
• 제23권10호
• /
• pp.1439-1444
• /
• 2002

6-Nitroquipazine has higher binding affinity for SERT than other selective serotonin reuptake inhibitors. We have prepared 6-nitroquipazine based rhenium complexes which would lead to the development of potential SPECT imaging agents with $^{99m}Tc$ for 5-HT transporter.