• Title/Summary/Keyword: CoTi

Search Result 1,695, Processing Time 0.03 seconds

Synthesis of Li-Zr incorporated mesoporous $TiO_2$ and its application in $CO_2$ adsorption ($TiO_2$ 담지체에 합성된 Li-Zr 메조포러스 분자체 ; 이산화탄소 흡착 응용)

  • Bhagiyalakshmi, Margandan;Peng, Mei Mei;Hemalatha, Pushparaj;Ganesh, Mani;Jang, Hyun-Tae
    • Proceedings of the KAIS Fall Conference
    • /
    • 2010.11a
    • /
    • pp.110-114
    • /
    • 2010
  • Li-incorporated mesoporous $TiO_2$ materials with various pore-sized istributions were synthesized by using triblockcopolymers via a sol-gel process in a queous solution. The properties of the se materials were characterized by HR-TEM, XRD, and BET analysis. All particles have spherical morphology with a diameterrange of $1-3{\mu}m$. The mesoporous $TiO_2$ materials calcined at $400^{\circ}C$ and their specific surface area, average pore size and crystallite sizes were 210 $m^2g^{-1}$, 6.4 nm and 8.8 nm respectively. The Li-incorporated mesoporous $TiO_2$ were tested for $CO_2$ adsorption and its adsorption capacity is 90mg/g. The Li-incorporated mesoporous $TiO_2$ ar eobserved to be thermally stable, recyclable and greens or bent for $CO_2$ capture. The effect of bimetallic $ZrLiTiO_2$ is also studied for $CO_2$ adsorption.

  • PDF

Continuous Wet Oxidation of TCE over Supported Metal Oxide Catalysts (금속산화물 담지촉매상에서 연속 습식 TCE 분해반응)

  • Kim, Moon Hyeon;Choo, Kwang-Ho
    • Korean Chemical Engineering Research
    • /
    • v.43 no.2
    • /
    • pp.206-214
    • /
    • 2005
  • Heterogeneously-catalyzed oxidation of aqueous phase trichloroethylene (TCE) over supported metal oxides has been conducted to establish an approach to eliminate ppm levels of organic compounds in water. A continuous flow reactor system was designed to effect predominant reaction parameters in determining catalytic activity of the catalysts for wet TCE decomposition as a model reaction. 5 wt.% $CoO_x/TiO_2$ catalyst exhibited a transient period in activity vs. on-stream time behavior, suggesting that the surface structure of the $CoO_x$ might be altered with on-stream hours; regardless, it is probable to be the most promising catalyst. Not only could the bare support be inactive for the wet decomposition reaction at $36^{\circ}C$, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Very low TCE conversion appeared for $TiO_2$-supported $NiO_x$ and $CrO_x$ catalysts. Wet oxidation performance of supported Cu and Fe catalysts, obtained through an incipient wetness and ion exchange technique, was dependent primarily on the kinds of the metal oxides, in addition to the acidic solid supports and the preparation routes. 5 wt.% $FeO_x/TiO_2$ catalyst gave no activity in the oxidation reaction at $36^{\circ}C$, while 1.2 wt.% Fe-MFI was active for the wet decomposition depending on time on-stream. The noticeable difference in activity of the both catalysts suggests that the Fe oxidation states involved to catalytic redox cycle during the course of reaction play a significant role in catalyzing the wet decomposition as well as in maintaining the time on-stream activity. Based on the results of different $CoO_x$ loadings and reaction temperatures for the decomposition reaction at $36^{\circ}C$ with $CoO_x/TiO_2$, the catalyst possessed an optimal $CoO_x$ amount at which higher reaction temperatures facilitated the catalytic TCE conversion. Small amounts of the active ingredient could be dissolved by acidic leaching but such a process gave no appreciable activity loss of the $CoO_x$ catalyst.

Effects of Annealing Treatments on Microstructure and Mechanical Property of co-sputtered TiNi Thin Film (Co-sputtering에 의해 증착된 TiNi 박막의 미세조직 및 기계적성질에 미치는 어닐링 열처리 효과)

  • Park, S.D.;Baeg, C.H.;Hong, J.W.
    • Journal of the Korean Society for Heat Treatment
    • /
    • v.21 no.1
    • /
    • pp.26-32
    • /
    • 2008
  • Effects of annealing treatment on microstructure and mechanical property of co-sputtered TiNi thin films were studied. As-deposited films showed amorphous state. However, above annealing temperature of $500^{\circ}C$ martensite phase (B19'), precipitate phase ($Ti_2Ni$) and a small amount of parent phase ($B_2$) were present, and phase transformation behaviors were three multi-step phase transformations $B19^{\prime}{\rightarrow}B_2$ and $B_2{\rightarrow}R-phase$ and $R-phase{\rightarrow}B19^{\prime}$. Increase of martensite transformation temperature, increase of microhardness and Young's modulus of TiNi films annealed above $500^{\circ}C$ were discussed in terms of precipitate phase.

The electrical characteristics of ZnO-$TiO_2$ composite ceramics by CO gas (일산화탄소에 의한 ZnO-$TiO_2$ 세라믹 복합체의 전기적 성질)

  • Kim, Tae-Won;Choi, U-Sung;Park, Choon-Bae
    • Proceedings of the KIEE Conference
    • /
    • 1997.07d
    • /
    • pp.1439-1442
    • /
    • 1997
  • We investigated the electrical and CO sensing properties of ZnO-$TiO_2$ composite ceramics. The electrical conductivities and relative dielectric constants of $TiO_2$ added ZnO increased with increasing $TiO_2$ content in air. The calculated dielectric constants of 3mol%, 5mol%, and 7mol% $TiO_2$ added ZnO were 7, 13, and 120, respectively. The measured CO sensivities were $1{\sim}6.42$ in the temperature range from $100^{\circ}C$ to $400^{\circ}C$.

  • PDF