수소생산 공정에서의 이산화탄소 포집

홍연기,Yeon Ki, Hong 한국교통대학교 융복합기술연구소 2022 융ㆍ복합기술연구소 논문집 Vol.12 No.1

Interest in hydrogen production to respond to climate change is increasing. Until now, hydrogen has been mainly produced through the SMR (Steam Methane Reforming) process using natural gas. A large amount of CO₂ is emitted in the hydrogen production process through SMR, and the gas flow including CO₂ generated in the SMR process has different characteristics for each emission source, so it is important to apply a suitable CO₂ capture process. In the case of PSA tail gas or synthesis gas, the applicability of an amine-based process has been confirmed or demonstrated close to a commercial level. However, in the case of the flue gas generated from the reformer, it is still difficult to apply the conventional amine-based process because the partial pressure of CO₂ is relatively low. Energy-saving innovative absorbents such as phase separation absorbents can be a solution to these difficulties.

글리세린 유래 1,3-propanediol의 제조 기술동향

홍연기 忠州大學校 2009 한국교통대학교 논문집 Vol.44 No.-

PTT[Poly(trimethyleneterephthalate)] is produced by the condensation of TPA(terephthalic acid) or DMT(dimethyl terephthalate) and 1,3-PDO(1,3-propanediol). Its chemical structure and condensation method are very similar to those of PET[Poly(ethylene terephthalate)]. The main raw material of PTT synthesis is 1,3-PDO which have been produced by chemical synthesis processes. Recently, the biological production of 1,3-PDO was begun. This paper will review briefly (1) need of biological production of 1,3-PDO (2) market status of PTT and (3) research trends of 1,3-PDO production.

자동차용 폐 삼원촉매로부터의 희귀금속 회수공정 기술 동향

홍연기,Hong, Yeon Ki 한국교통대학교 융복합기술연구소 2011 융ㆍ복합기술연구소 논문집 Vol.1 No.1

The car industry is one of the technological applications which more rare earth metals employes as three-way catalysts. Therefore, the recovery of rare earth metals from the used automotive three-way catalysts could be important source to obtain these metals. This work presents the analysis of market and demand for rare earth metal in automotive three-way catalyst and introduces the dry and the wet processes for the recovery of rare earth metals from used three-way catalyst. Finally, the alternative methods to conventional wet processes was simply suggested based on the economic and ecological point of view.

Nd-Fe-B계 소결자석의 자기적 특성에 미치는 첨가원소와 결정립 분포의 영향

홍연기,김종오,Hong, Yeon-Gi,Kim, Jong-O 한국재료학회 1998 한국재료학회지 Vol.8 No.9

합금의 주조시 냉각속도가 $\textrm{Nd}_{16}\textrm{Fe}_{72}\textrm{V}_{4}\textrm{B}_{8}$ 소결자석의 결정립 분포와 착자특성에 미치는 영향에 대하여 조사하였다. 냉각속도가 높은 Cu mold를 사용하여 제작한 시료는 좁은 결정립 분포와 착자특성의 향상을 보였다. B화합물을 생성하는 Cr, Mn, Nb 그리고 w과 같은 첨가원소가 Nd-Fe-B계 소결자석의 착자특성에 미치는 영향에 대해서도 조사하였다. Cr이나 W첨가는 보자력의 향상에 효과적이고 $\textrm{Nd}_{16}\textrm{Fe}_{72}\textrm{Cr}_{4}\textrm{B}_{9}$합금은 $\textrm{Nd}_{16}\textrm{Fe}_{72}\textrm{V}_{4}\textrm{B}_{8}$합금과 비슷한 착자특성을 보였다. The influence of casting cooling rate during the preparation of ingots on the grain size distribution and the magnetizing ability of $\textrm{Nd}_{16}\textrm{Fe}_{72}\textrm{V}_{4}\textrm{B}_{8}$ sintered magnets were investigated. Sintered magnets prepared from copper mold which allow a higher cooling rate, show a smaller grain size distribution and god magnetizing ability. The effects of adding bride forming elements, such as Cr, Mn, Nb, and W on the magnetic properties of Nd-Fe-B sintered magnets were also investigated. Both Cr and W addition increase coercivity and the resultant $\textrm{Nd}_{16}\textrm{Fe}_{72}\textrm{Cr}_{4}\textrm{B}_{9}$ alloy exhibits a similar magnetizing ability in comparison with $\textrm{Nd}_{16}\textrm{Fe}_{72}\textrm{V}_{4}\textrm{B}_{8}$ alloy.

미국의 셰일가스 개발과 석유화학 산업의 영향

홍연기,Hong, Yeon Ki 한국교통대학교 융복합기술연구소 2016 융ㆍ복합기술연구소 논문집 Vol.6 No.1

In this paper, the present status of shale gas development was briefly introduced and intended the growing importance and shale gas as a source of chemicals. The large amounts of shale are expected to be produced thereby, a wealth of methane and ethane will be provided as a raw material of ethylene. This manuscript also focus on the influence of potential volumes of shale gas on petrochemical industry, especially domestic one based on naphtha cracking because ethane cracking can offer cost effective ways to convert methane to higher value chemicals.

이성분 용매 추출에 의한 미세조류로 부터의 바이오디젤용 지질 분리

홍연기,김정배,Ng, K. Y. Simon 한국태양에너지학회 2011 한국태양에너지학회 논문집 Vol.31 No.6

Various single solvents were tested to find the effective solvent for the extraction of algae oil from wet-form Chlorella minutissima. In the case of single solvents, their extractabilities for algae oil were increased with their polarity because the water in wet algae cell is to form a solvent shell around the lipids. Based on these results, the wet-form algae samples were treated with a polar alcohol solvent and then a nonpolar solvent was added in algae residue. In the algae oil extraction by ethanol/n-hexane, total lipid contents were 40-50% and composition of triglyceride in extracted oil was 46.50%. Considering solvent toxicity of conventional solvent mixture such as chloroform and methanol for algae oil extraction, the ethanol/n-hexane system was identified as the effective one for the oil extraction from wet-form Chlorella minutissima

국내 바이오에너지 보급에 따른 온실가스 저감 평가

홍연기,Hong, Yeon Ki 한국교통대학교 융복합기술연구소 2014 융ㆍ복합기술연구소 논문집 Vol.4 No.1

Recently, the development of renewable energy sources in Korea has been needed due to climate change. One of powerful alternative energy resources to mitigate emission is to switch conventional fuels to renewable energy, such as bioenergy. In this study, current status of bioenergy conversion technology and its supply in Korea was investigate. Based on theoretical, technical and realizable potential of biomass in Korea, the amount of reduction of green house gases was estimated. The results shown that the contribution of biomass on 2020 reduction target of green house gases emission in power generation was $513,000\;tCO_2/yr$ and utilization ratio of technical potential of biomass was 6.4%. For the effective supply of bioenergy in Korea, more exact estimation of realizable potential of biomass in Korea and stable supply sources are needed.

반응추출법을 통한 bioproduct의 분리정제

홍연기,홍원희 한국화학공학회 2007 화학공학의이론과응용 Vol.10 No.1

Bioproduct의 대량 생산을 위한 생물공정의 개발에 있어서 저비용, 고효율의 분리공정의 개발은 생물공정 전체의 경제성 측면에서 봤을 때 매우 중요하다. 반응추출법은 경제적인 생물 분리공정 중 하나로서 범용 bioproduct의 생산에 적합한 것으로 알려져 있다. 본 논문에서는 반응추출법의 정의와 원리에 대해 살펴보고 지금까지 반응추출법에 대한 연구현황에 대해 발효 유기산, 항생제, 그리고 단백질의 분리정제를 중심으로 논의하였다. 또한 상부공정의 생산 효율 향상 및 전체 생물공정의 경제성을 위한 발효-추출 복합공정에 대한 연구를 소개하고 향후 반응추출 공정 개발에 있어 기술적으로 해결해야 할 문제들을 제시하였다.

반응추출법을 통한 카르복실산의 분리정제

홍연기,이경원 忠州大學校 2004 한국교통대학교 논문집 Vol.39 No.2

Carboxylic acids are examples of materials with wide industrial applications and their high potential. This article described the principles of reactive extraction along with the extraction characteristics of amine extractants with considering the effect of the amine class and chain length. And a brief overview of the current research on reactive extraction of carboxylic acids such as recovery of citric acid, selective amine-based extraction, and extractive fermentation was given. In extractive fermentation of carboxylic acids, strategies for reducing solvent toxicity were also suggested. Finally, regeneration and stripping processes were explained.

정밀연삭 표면 형상과 레이저 산란 영상과의 상관관계 고찰에 관한 연구

홍연기,김경범 忠州大學校 2009 한국교통대학교 논문집 Vol.44 No.-

In this paper, the correlation between grinding surface microtopography and its scattered image has been experimentally investigated using laser scattering. The optimum parameter conditions on grinding surfaces are selected using the design of experiment under laser scattering image acquisition device. The optimum parameters result in distinctive scattered images. It is shown that the dominant feature values are linearly increased as grinding surface roughness. This result can be used as a core factor for the identification of grinding surface microtopography based on laser scattering image.