• Korean Membrane Journal
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• 제1권1호
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• pp.1-7
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• 1999

Pd-ceramic composite membranes and catalytic membrane reactors(CMR) have been studied for hydrogen and its isotopes (deuterium and tritium) purification and recovery in the fusion reactor fuel cycle. Particularly a closed-loop process has been studied for recovering tritium from tritiated water by means of a CMR in which the water gas shift reaction takes place. The development of the techniques for coating micro-porous ceramic tubes with Pd and Pd/Ag thin layers is described : P composite membranes have been produced by electroless deposition (Pd/Ag film of 10-20 $\mu$m) and rolling of thin metal sheets (Pd and Pd/Ag membranes of 50-70 $\mu$m). Experimental results of the electroless membranes have shown a not complete hydrogen selectivity because of the presence of some defects(micro-holes) in the metallic thin layer. Conversely the rolled thin Pd and Pd/ag membranes have separated hydrogen from the other gases with a complete selectivity giving rise to a slightly larger (about a factor 1.7) mass transfer resistance with respect to the electroless membranes. Experimental tests have confirmed the good performances of the rolled membranes in terms of chemical stability over several weeks of operation. Therefore these rolled membranes and CMR are adequate for applications in the fusion reactor fuel cycle as well as in the industrial processes where high pure hydrogen is required (i.e. hydrocarbon reforming for fuel cell)

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.674-678
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• 2002

The dehydrogenation of propane to propylene has been studied in an isothermal high-temperature shell-and-tube membrane reactor containing a Pd-coated ${\psi}$-Al2O3 membrane and a Pt/K/Sn/Al2O3 packed catalyst . A tubular Pd-coated ${\psi}$-Al2O3 membrane was prepared by an electroless plating method. This membrane showed high hydrogen to nitrogen permselectivities (PH2N2 = 10-50) at 400 $^{\circ}C$ and 500 $^{\circ}C$ with various transmembrane pressure drops. The employment of a membrane reactor in the dehydrogenation reaction, which selectively separates hydrogen from the reaction mixture along the reaction path, can greatly increase the conversion and enable operation of the reactor at lower temperatures. High hydrogen permselectivity has been confirmed as a key factor in determining the reactor performance of conversion enhancement.

• 멤브레인
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• 제28권5호
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• pp.297-306
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• 2018

본 총설은 분리막기술이 적용된 수소생산에 대한 개론으로, 특히, 암모니아를 수소운반체로 이용하는 수소생산에 대한 연구결과를 중점적으로 서술하였다. 암모니아를 수소운반체로 적용한 수소생산은 추가적인 탄소생성이 없다는 점 외에 여러 측면에 있어 이점이 있다. 많은 연구들이 고순도 수소 분리 및 생산을 위한 분리막 개발을 위해 진행되고 있으며, 이들 중 팔라듐을 기본으로 한 분리막(예를 들어, 다공성 세라믹 또는 다공성 금속 지지체와 팔라듐 합금의 얇은 선택층으로 이루어진 분리막)에 대한 연구가 활발하다. 반면에, 효율적인 암모니아 분해를 위해서는 주로 루테늄 촉매가 적용되고 있으며, 루테늄과 지지체 및 촉진제로 이루어진 루테늄에 기반을 둔 촉매에 대한 연구발표가 다수 존재한다. 수소생산을 위한 분리막 반응기 형태로는 충전층, 유동층, 그리고 마이크로반응기 등이 있으며, 이들의 최적화 및 원활한 물질전달 연구는 현재진행형이다. 또한, 높은 암모니아 분해율, 고순도 수소생산 및 높은 수소생산율을 얻기 위해 분리막과 촉매의 다양한 조합에 대한 연구 및 분리막과 촉매의 역할을 동시에 구현할 수 있는 분리막에 대한 연구가 발표되고 있다.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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• pp.43-47
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• 1999

Pd-ceramic composite membranes and catalytic membrane reactors(CMR) have been studied for hydrogen purification and recovery in th fusion reactor fuel cycle. The development of techniques for coating microporous ceramic tubes with Pd and Pd/Ag layers is described: composite membranes have been produced by electroless deposition (Pd/Ag film of 10-20${\mu}{\textrm}{m}$) and rolling of thin metal sheet (Pd and Pd/ Ag membranes of 50-70 ${\mu}{\textrm}{m}$). Experimental results on electroless membranes showed that the metallic film presented some defects and the membranes had not complete hydrogen selectivity . Then the catalytic membrane reactors with electroless membranes can be applied for some industrial processes that do not require a complete separation of the hydrogen (i.e. in the dehydrogenation of hydrocarbons). The rolled thin Pd/Ag membranes separated the hydrogen from the other gas with a complete selectivity and exhibited a slightly larger (about a factor 1.7) mass transfer resistance with respect to the electroless membranes. Experimental tests confirmed the good performances in terms of durability.

• 한국압력기기공학회 논문집
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• 제10권1호
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• pp.44-50
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• 2014

There were many flaw issues of reactor vessel head penetration in USA fleets. USNRC issued 10CFR50.55a to implement reactor vessel head penetration ultrasonic examination performance demonstration(PD) in US for enhancement of inspection reliability. After September 2009, all US utilities inspected their RVHP with PD qualified system. Korea Hydro and Nuclear Power Company(KHNP) have developed reactor vessel head penetration performance demonstration system for ultrasonic test to apply for pressurized light-water reactor power plants in accordance with 10CFR50.55a since September 2011. RVHP configuration surveying and analysis, code requirement analysis, and performance demonstration specimen design were performed up to this day. Fingerprinting of manufactured specimen, development of test data management program, development of operation procedure, input of flawed data, and development of final report will be performed for the next step. This paper describes the development status of the performance demonstration system for reactor vessel head penetration ultrasonic examination in Korea.

• 한국응용과학기술학회지
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• 제31권4호
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• pp.541-548
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• 2014

This study was performed to obtain high conversion efficiency of $C_7H_8$ using non-thermal plasma and metal-supported catalyst. Adsorption-desorption characteristics of toluene was performed using 4A type (Zeolite) filled in a concentration reactor. Through this test, it was found that the concentration reactor has 0.020 g/g of adsorption capacity (at ambient temperature and pressure) and 3,600 ppm of desorption property at $150^{\circ}C$ (with in 20 min). In case of developed catalyst, toluene decomposition rate of Pd-AO (Pd coated catalyst) was better than Pd/Cu-AO and Pd/Ag-AO (Pd/Ag composite metal catalyst). Developed non-thermal plasma system was obtained flame amplification effect using injection process of desorbed tolune, and 98% of removal efficiency.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.262-262
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• 2012

Modifications of graphenes have been studied for catalytic applications due to their advantages such as high surface area, conductivity and thermal stability. In this research, individual graphene oxide (GO) sheets were exfoliated from graphite using Hummers and Offeman method. Pd nano-particles were deposited on the GO surface using Pd2+ ion exchange where hydroxyl groups on the GO act as nucleation sites of Pd nanoparticles and their dispersions. The thermal treatments of the Pd-GO in H2 flow produced Pd-Graphene nanocomposites. Their catalytic performances in Sonogashira reaction were investigated. Morphological and chemical structures of the GO, Pd-GO, and Pd-Graphene were investigated using FT-IR, XRD, TEM, STEM, and XPS. The catalytic performances have been investigated using microwave reactor.

• 한국수소및신에너지학회논문집
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• 제27권3호
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• pp.264-269
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• 2016

A simple dry chemical approach was developed in order to load palladium (Pd) as a promoter on Pt/gas diffusion electrode (GDE) for polymer electrolyte membrane fuel cell (PEMFC). Palladium(II) bis (acetylacetonate), $Pd(acac)_2$ was sublimed, penetrated into Pt/GDE and then reduced to Pd nanoparticles simultaneously without any reducing agent and any solvent in a glass reactor of $N_2$ atmosphere at $180^{\circ}C$ for 3, 5 and 15 min. Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.

• 대한화학회지
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• 제46권1호
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• pp.57-63
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• 2002

CTA(crude terephthalic acid)의 수소화 정제 반응이 고온의 회분식반응기에서 PdRu/CCM(carbon-carbonaceous composite material) 촉매 상에서 수행되었다. 반응 시간에 따른 In(4-CBA; 4-carboxybenzaldehyde)의 의존도가 선형성을 보임에서 수소화 정제는 1차 속도론을 따름을 알 수 있었다. 촉매량에 따른 반응 속도의 선형성에서 조사된 반응 조건은 정제 반응을 잘 대변할 수 있음을 알 수 있었다. 반응 전환율이 증가하면(4-CBA가 감소하면) 고체 및 액체의 p-toluic acid(p-tol)의 농도는 증가하였으나 벤조산(BA)의 농도는 크게 변하지 않았다. 4-CBA 농도가 대략 0.15% 이하일 때에는 PTA의 AT(alkalitransmittance)는 4-CBA농도에 반비례하며 이는 4-CBA의 수소화에 따라 발색물질도 제거 됨을 보여 준다. 4-CBA농도가 약 0.2% 이상이면 AT는 일정하였는데 이는 4-CBA 자체는 발색 효과를 가지지 않음을 보여준다. (0.3%Pd-0.2%Ru)/CCM 촉매는 0.5%Pd/C 상업 촉매에 비해 초기 활성은 낮으나, 상업 공장 반응기에서 사용한 후에는 오히려 큰 잔존 활성을 보였고 PdRu/CCM 촉매는 루테늄 함량이 약 $0.2{\sim}0.35%$ 일 때 활성의 상승효과를 보였다. PdRu/CCM 촉매는 0.5%Pd/C 상업 촉매를 대체할 가능성이 높음을 알 수 있다.

• Korean Membrane Journal
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• 제5권1호
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• pp.68-74
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• 2003

Methane steam reforming (MSR) reaction for hydrogen production was studied in a membrane reactor (MR) using two tubular membranes, one Pd-based and one of porous alumina. A higher methane conversion than the thermodynamic equilibrium for a traditional reactor (TR) was achieved using MRs. The experimental temperature range was 350-500$^{\circ}C$; no sweep-gas was employed during reaction tests to avoid its back-permeation through the membrane and the steam/methane molar feed ratio (m) varied in the range 3.5-5.9. The best results (the difference between the MR conversion and the thermodynamic equilibrium was of about 7%) were achieved with the alumina membrane, working with the highest steam/methane ratio and at 450$^{\circ}C$. Silica membranes prepared at KRICT laboratories were characterized with permeation tests on single gases (N$_2$, H$_2$ and CH$_4$). These membranes are suited for H$_2$ separation at high temperature.