Kwonpil Park

New Method for the Preparation of Solid Polymer Electrolyte Based on Poly(vinylidene fluoride-co-hexafluoropropylene)

A novel solid polymer electrolyte (pore-gel SPE) has been found to provide superior SPE having a high conductivity, good mechanical strength and low solution leakage. This pore-gel SPE was prepared from gelation in pores of polymer membrane with electrolyte solution including solvent. The conductivity of pore-gel type PVDF-HFP/ TEABF4 (Tetraethylammomium tetrafluoroborate) membrane can reach 1.6×10-1 Scm-1. The tensile strength of this membrane was 4,000 kPa, which is about 23 times larger than that of gel-type SPE with the same composition. Poregel SPE reduced solution leakage to 0%, compared with 2% of hybrid-type SPE after 2.0 hr leakage test in PVDFHFP/ TEABF4 membrane.

Characteristics of Poly(arylene ether sulfone) Membrane for Vanadium Redox Flow Battery

최근에 대용량 에너지 저장 시스템으로 레독스 흐름전지(Redox Flow Battery, RFB)가 활발히 연구·개발되고 있다. 불소계막을 대신할 저가의 탄화수소막이 RFB막으로 주목받고 있다. 본 연구에서는 Poly(arylene ether sulfone) (PAES)막을 사용해 고가의 불소계막과 그 특성을 바나듐 레독스 흐름전지(VRB, Vanadium Redox Flow Battery)조건에서 비교하였다. 바나듐 이온투과도, 이온 교환 용량, OCV 변화, 팽윤, 충·방전 곡선, 에너지 효율 등을 측정했다. PAES 막은 Nafion 117막에 비해 바나듐 이온투과도가 낮고, 이온교환용량은 커서 Nafion 117을 사용한 RFB보다 에너지 효율이 높았다.

Study on Conversion of Carbon Dioxide to Methyl Alcohol over Ceramic Monolith Supported CuO and ZnO Catalysts

Methyl alcohol is one of the basic intermediates in the chemical industry and is also being used as a fuel additive and as a clean burning fuel. In this study, conversion of carbon dioxide to methyl alcohol was investigated using catalytic chemical methods. Ceramic monoliths (M) with were used as catalyst supports. Monolith-supported CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using ICP analysis, TEM images and XRD patterns. The catalytic activity for carbon dioxide hydrogenation to methyl alcohol was investigated using a flow-type reactor under various reaction temperature, pressure and contact time. In the preparation of monolith-supported CuO-ZnO catalysts by wash-coat method, proper concentration of precursors solution was 25.7% (w/v). The mixed crystal of CuO and ZnO was well supported on monolith. And it was known that more CuO component may be supported than ZnO component. Conversion of carbon dioxide was increased with increasing reaction temperature, but methyl alcohol selectivity was decreased. Optimum reaction temperature was about under 20 atm because of the reverse water gas shift reaction. Maximum yield of methyl alcohol over CuO-ZnO/M catalyst was 5.1 mol% at and 20 atm.

Catalytic Activity of Nanosized CuO-ZnO Supported on Titanium Chips in Hydrogenation of Carbon Dioxide to Methyl Alcohol.

In this study, titanium chips (TC) generated from industrial facilities was utilized as TiO2 support for hydrogenation of carbon dioxide (CO2) to methyl alcohol (CH3OH) over Cu-based catalysts. Nano-sized CuO and ZnO catalysts were deposited on TiO2 support using a co-precipitation (CP) method (CuO-ZnO/TiO2), where the thermal treatment of TC and the particle size of TiC2 are optimized on CO2 conversion under different reaction temperature and contact time. Direct hydrogenation of CO2 to CH3OH over CuO-ZnO/TiO2 catalysts was achieved and the maximum selectivity (22%) and yield (18.2%) of CH3OH were obtained in the range of reaction temperature 210-240 degrees C under the 30 bar. The selectivity was readily increased by increasing the flow rate, which does not affect much to the CO2 conversion and CH3OH yield.

Nanosized CuO and ZnO Catalyst Supported on Honeycomb-Typed Monolith for Hydrogenation of Carbon Dioxide to Methyl Alcohol.

The greenhouse effect of carbon dioxide (CO2) has been recognized as one of the most serious problems in the world. Conversion of CO2 to methyl alcohol (CH3OH) was studied using catalytic chemical methods. Honeycomb-typed monolith used as catalyst support was 400 cell/inch2. Pretreatment of the monolith surface was carried out by thermal treatment and acid treatment. Monolith-supported nanosized CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using SEM, TEM, and XRD. The catalytic activity for CO2 hydrogenation to CH3OH was investigated using a flow-type reactor with varying reaction temperature, reaction pressure and contact time. Conversion of CO2 was increased with increasing reaction temperature, but selectivity to CH3OH was decreased. Optimum reaction temperature was about 250 degrees C under 20 atm. Because of the reverse water gas shift reaction.