Time filter

Source Type

Cheongwon gun, South Korea

Cho W.-S.,Soongsil University | Cho W.-S.,Seoul Waterworks Research Institute | Lee K.-H.,Soongsil University | Chang H.-J.,Wonik Materials Co | And 2 more authors.
Korean Journal of Chemical Engineering | Year: 2011

The separation/concentration of SF6, a strong greenhouse gas, of 1.3% in N2 was investigated using pressure-temperature swing adsorption (PTSA) with activated carbon. To screen an effective adsorbent to be used for PTSA, adsorption isotherms on the selected adsorbents were obtained. Among the studied adsorbents, AC-1, a coconut-shell based commercial activated carbon, showed the largest adsorption amount of 3.5 mmol-SF6/g-carbon at 303.65 K and 3 atm and the highest selectivity among the adsorbents tested. Its adsorption isotherm was well fit into Langmuir-Freundlich model. Before feasibility test of PTSA, a series of experiments were performed to investigate the effect of operating parameters including adsorption pressure, feed flow rate, desorption temperature and evacuation time on the PTSA performance using the 3-step PTSA cycle (pressurization, adsorption and regeneration-recovery). As the adsorption pressure, desorption temperature and evacuation time were increased, respectively, purity and recovery increased. Increasing the feed flow rate resulted in low purity and recovery. The maximum purity of 19.5% and recovery of 50.1% were obtained with adsorption pressure of 2.5 atm, desorption temperature of 200 °C and evacuation of 1 hour. © 2011 Korean Institute of Chemical Engineers, Seoul, Korea. Source

Chae H.J.,Kyungpook National University | Lee S.C.,Kyungpook National University | Lee S.J.,Korean Intellectual Property Office | Cho M.S.,Kyungpook National University | And 6 more authors.
Journal of Industrial and Engineering Chemistry | Year: 2016

The SO2 sorption properties of dry potassium-based sorbents, prepared by impregnation of various supports with potassium carbonate, were investigated at the various water vapor concentrations at a level of 5000ppm of SO2. It was found that alkali metal-based sorbents promoted with potassium carbonate could be used as a sorbent for SO2 sorption at low temperatures (between 30°C and 60°C). In particular, the potassium-based sorbents showed an excellent SO2 sorption capacity of about 310mg SO2/g sorbent in the presence of water vapor, while in the absence of water vapor, their SO2 sorption capacities decreased. © 2016 The Korean Society of Industrial and Engineering Chemistry. Source

Kim Y.L.,Wonik Materials Co | Park S.J.,Wonik Materials Co | Choi H.,Wonik Materials Co | Baek J.-M.,Wonik Materials Co | And 3 more authors.
Journal of Chemical and Engineering Data | Year: 2014

Isothermal vapor-liquid equilibrium (VLE) data were measured for the binary systems of octafluoropropane + octafluorocyclobutane and hexafluoropropylene oxide + octafluorocyclobutane system at the temperature range from 263.15 K to 303.15 K. The experiments were carried out with a circulating-type equilibrium apparatus including online gas chromatography analysis. The VLE data were correlated well by the Peng-Robinson equation of state using the Wong-Sandler mixing rules involving the NRTL model. All the binary parameters of these systems and the average absolute deviations (AADs) in terms of saturated pressure and vapor phase composition between the experimental and calculated values are represented. © 2014 American Chemical Society. Source

Choi H.Y.,Wonik Materials Co | Park S.J.,Wonik Materials Co | Seo D.,Wonik Materials Co | Baek J.-M.,Wonik Materials Co | And 4 more authors.
International Journal of Hydrogen Energy | Year: 2015

Ammonia borane (NH3BH3), as a source material for energy generation and hydrogen storage, has attracted growing interest due to its high hydrogen content. We have investigated the synthesis of ammonia borane from diborane (B2H6) and ammonia (NH3) utilizing a low-temperature process. From our results, a maximum synthetic yield of 92.2% was obtained, for an ammonia borane complex of 0.35M. The diammoniate diborane (DADB) was detected in about 5-10mol% within the solid ammonia borane by solid-state 11B-NMR analysis. The synthesized solid ammonia borane products were studied to characterize hydrogen release upon thermal dehydrogenation. © 2015 Hydrogen Energy Publications, LLC. Source

Discover hidden collaborations