NEWS & INFORMATION FOR CHEMICAL ENGINEERS, Vol. 31, No. 2, 2013…217 Korean Journal of Chemical Engineering,
Vol.30, No.2, 253-261, 2013
Waste paper sludge as a potential biomass for bio-ethanol production
Prasetyo J, Park EYAbstract - This review describes the utilization of paper sludge (PS), which is waste from the pulp and paper industry. Its advantages make PS the cellulosic biomass with the most potential for bio-refinery research and applicable for industrial scale. Some of the grain based biofuels and chemicals have already been in commercial operation, including fuel ethanol or biochemical products. Unfortunately, research and application of PS are yet in their infancy and suffer from large scale because of low productivity. Reviewing the many researches that are working at the utilization of PS for bio-refineries could encourage the utilization of PS from laboratory research to be applied in industry. For this reason, PS usage as industrial raw material will be effective in solving the environmental problems caused by PS with clean technology. In addition, its conversion to bio-ethanol could offer an alternative solution to the energy crisis from fossil fuel. Two methods of PS utilization as raw material for bio-ethanol production are introduced. The simultaneous saccharification and fermentation (SSF) using cellulase produced by A. cellulolyticus and thermotolerant S. cerevisiae TJ14 gave ethanol yield 0.208 (g ethanol/g PS organic material) or 0.051 (g ethanol/g PS). One pot bioethanol production as a modified consolidated biomass processing (CBP) technology gave ethanol yield 0.19 (g ethanol/g Solka floc) and is considered to be the practical CBP technology for its minimizing process.
Korean Journal of Chemical Engineering, Vol.30, No.2, 357-363, 2013
Synthesis of a novel carbon nanofiber structure for removal of lead
Faghihian H, Kooravand M, Atarodi HAbstract - A new structure of carbon nanofibers was synthesized by chemical vapor deposition method. Kaolin was used as substrate and cyclohexanol and ferrocene as carbon source and catalyst, respectively. The morphology of the product was studied by scanning electron microscopy. Carbon nanofiber was modified with a mixture of nitric acid and sulfuric acid to enhance its adsorption capacity. The presence of functional groups on the treated adsorbent was assessed by FT-IR spectroscopy. The surface activity of the oxidized sample was estimated by Boehm’s titration. The pH(PZC)of the samples was also measured. The adsorbent was then used for adsorption of Pb2+at different experimental conditions. The optimized capacity of 211mg·g-1) was obtained. Kinetic and thermodynamic of the reaction were studied. It was concluded that the adsorption process is spontaneous and endothermic. Equilibrium data were well fitted to the Langmuir model and the pseudo-second-order kinetic model described the adsorption process.
Korean Journal of Chemical Engineering, Vol.30, No.2, 482-487, 2013
Surface plasmon resonance study of (positive, neutral, negative) vesicles rupture by AgNPs’
attack for screening of cytotoxicity induced by nanoparticles
Umh HN, Kim YAbstract - As the use of nanomaterials in industrial and commercial applications is growing, official reports concerning possible environmental and health effects of nanoparticles are also steadily increasing. Many toxicological studies on the adverse effects of silver nanoparticles (AgNPs) have used living organisms, which is a time consuming process. Therefore, we propose an alternative method to assess the in-vivo and in-vitro cytotoxicity of nanomaterials, involving a fast and simple screening procedure for vesicle rupture or fusion by the attack of AgNPs. With the assumption that particle
Editor’s Choice
218…NICE, 제31권 제2호, 2013
interaction between AgNPs and vesicles is induced by electrostatic repulsion or attraction of surface charge, three vesicles with different charges (positive, neutral, and negative) were prepared and they were dispersed with AgNPs in different pH (3, 7, and 10) solutions to control the surface charge of AgNPs. Based on the results of vesicle rupture analyzed by SPR and TEM, screening of cell rupture through vesicles by AgNPs’attack is determined to be most suitable at pH 7.
Korean Journal of Chemical Engineering, Vol.30, No.3, 509-517, 2013
Selective oxidation of refractory sulfur compounds for the production of low sulfur transportation fuel
Jeong KE, Kim TW, Kim JW, Chae HJ, Kim CU, Park YK, Jeong SY
Abstract - The current technologies for achieving low sulfur in diesel fuel are based on hydrotreating, which requires high temperature, high pressure and excessive supply of hydrogen. Oxidative desulfurization (ODS) is considered one of the promising new methods for super deep desulfurization, which could be carried out under very mild conditions (atmospheric pressure, <100 ℃) without consumption of hydrogen. In this paper, development status of ODS process by major licensors are described as well as general concepts of ODS reaction. In addition, the ODS process has been categorized into single phasic and biphasic system according to the oxidants involved. Recent trends in both systems are reviewed in detail and future work is also proposed.
Korean Journal of Chemical Engineering, Vol.30, No.3, 620-625, 2013
Improved electrochemical performance of dye-sensitized solar cell via surface modifications of the working electrode by electrodeposition
Jang KI, Hong E, Kim JH
Abstract - Modifications of the working electrode with TiO2blocking or coating layers are carried by electrodeposition in TiCl3precursor solution. The results suggest that the electrodeposited TiO2blocking layer provides excellent agglutination between the FTO substrate and the active TiO2layer. In addition, the electrodeposited TiO2coating layer enhances the interconnections between the TiO2nanoparticles and the FTO substrate, and therefore it increases the electron transport efficiency. The morphology and crystalline structure of the electrodeposited TiO2layers are characterized by SEM, TEM, and XRD. The electrochemical impedance spectroscopy measurements show that the improved DSSC performance with the electrodeposited coating layer is mainly due to the increase in the lifetime of the conduction band electron in the TiO2
film. The photoelectron conversion efficiency of DSSC is increased from 3.47% to 5.38% by employing the TiO2
electrodeposited working electrode.
Korean Journal of Chemical Engineering, Vol.30, No.3, 733-738, 2013
Effect of silica nanoparticles on the phase inversion of liquid-liquid dispersions
Asadabadi MR, Abolghasemi H, Maragheh MG, Nasab PDAbstract - The effect of silica nanoparticles on phase inversion of liquid-liquid dispersions in a stirred vessel was investigated. The studied systems were toluene dispersed in water and vice versa. In the first set of experiments, phase inversion behavior of systems without Silica nanoparticles was evaluated and subsequent experiments were conducted in the presence of the nanoparticles. For this purpose, Silica nanoparticles of different concentrations (0.01, 0.03, 0.05, 0.07 wt%) were dispersed in water. The nanofluid stability was examined using an ultraviolet-visible (UV-vis) spectrophotometer. The results indicated that increase in silica nanoparticle concentrations up to 0.07 wt% led to increase in agitation speed of phase inversion 43-53.5% and 38.5-45% in the case of O/W and W/O dispersions, respectively.
Consequently, the tendency of dispersions to inversion diminished as nanoparticle concentrations increased. Finally, 0.05 wt% of silica nanoparticle was selected as the optimum on the range studied.
NEWS & INFORMATION FOR CHEMICAL ENGINEERS, Vol. 31, No. 2, 2013…219 Korean Chemical Engineering Research,
Vol.51, No.1, 1-9, 2013
제올라이트 촉매상에서의 알킬 방향족 화합물 전환 반응기구에 대한 최근 연구 동향 민
민형형기기, 홍홍석석봉봉
Abstract - 제올라이트 촉매를 이용한 알킬 방향족 화합물의 전환은 현대 석유화학 산업에서 큰 비중을 차지한 다. 본 총설에서는 제올라이트의 구조적 ·물리화학적 특성에 따른 알킬 방향족 화합물 전환 반응의 기구에 대 해 고찰하였다. 제올라이트의 형상선택성은 알킬 방향족 화합물 전환에 있어서 반응중간체의 생성을 조절함으 로써 반응 기구 및 생성물 분포에 직접적인 영향을 미친다. 다양한 알킬 방향족 화합물의 전환 반응에 대하여 반응 중간체의 구조 및 역할에 대한 고찰을 통해 지금까지 알려진 반응기구들을 정리하였다. 아울러 제올라이 트 촉매를 기초로 하는 향후 석유화학 공정 개발에 대한 전망을 기술하였다.
Korean Chemical Engineering Research, Vol.51, No.1, 10-24, 2013
공정개발을 위한 다규모 모사에서의 연구현황 임
임영영일일
Abstract - 본 논문은 과학 및 공학에서 폭넓게 연구되고 있는 다규모 모사(multiscale simulation; MSS)에 대하여 간단하게 그 현황을 살펴본 후, 이러한 MSS를 공정개발에 효과적으로 적용하기 위하여 공정개발을 위한 PD- MSS (MSS for process development)를 제시한다. 4단계로 제시된 PD-MSS는 PLS(공정수준모사), FLS(유체수준모 사), mFLS(미세유체수준모사), 그리고 MLS(분자수준모사) 로 구성된다. 각 규모의 특징과 주요 기법들, 그리고 이들 4개 규모 간 연관성을 설명한다. PD-MSS의 예로서 흡수탑, 유동층 반응기, 그리고 흡착공정의 모사가 소 개된다. 성공적인 다규모 모사(MSS)를 위하여 다규모적 화학공학 문제들에 대한 이해, 각 규모 및 규모간 자연 현상을 표현할 수 있는 모델 개발, 수학적 모델을 전산상에서 구현할 수 있도록 하는 소프트웨어 개발, 그리고 계산을 수행하는 하드웨어에서의 조화로운 발전이 필요하다. 다규모 모사는 모사결과의 정확도(accuracy), 컴 퓨터의 계산능력(computation capacity), 그리고 효율성 (efficiency)을 제한 조건으로 주어진 문제에 접근해야 할 것이다. 거시적 규모와 미시적 규모는 상대적으로 잘 정리되어 있지만, 이들 사이인 중간규모(mesoscale) 에서 의 모델은 병목현상을 보이고 있다. 따라서 물리적 현상을 신뢰성 있고, 정확하게 예측하기 위하여 중간규모에 대한 많은 연구가 요구된다. 시작단계에 불과한 PD-MSS는 공정개발에 있어서 시간과 비용을 절감할 수 있는 지속 가능한 기술로서 자리잡게 될 것이다.
Korean Chemical Engineering Research, Vol.51, No.1, 25-34, 2013
천연가스 액화공정의 최적설계 조
조현현준준, 여여영영구구, 김김진진국국
본 총설에서는 천연가스 액화공정의 최적설계에서 에너지 효율을 높이기 위해 고려해야 하는 주요 공정설계 인자들에 대한 논의와 상용 LNG 플랜트에서 이러한 인자들이 어떻게 적용되고 있는지에 대하여 살펴보았다.
압축기에서 소모되는 축일의 양을 최소화하기 위한 방법으로서 단일 냉매를 사용하는 냉각 사이클을 다단, 혹 은 중첩 구조로 설계하여 온도 범위가 넓은 영역에서 운용하는 방법과 혼합냉매를 사용하여 단순한 사이클 구 조를 유지하면서 최적 냉각공급 곡선을 유지하는 방법을 다루었고, 천연가스 액화조건에 맞추어 이러한 구조 들의 최적 조합을 구성하는 원리를 소개하였다. 열 통합(heat integration) 기법을 활용하여 상용화 공정들의 특징 을 도식적으로 고찰하였으며 아울러 에너지 효율 및 경제성에 대한 분석을 수행하였다. 또한 액화 공정 설계에 서 사용되는 대용량의 압축기들을 구동하는 에너지 시스템에 대한 설계 문제를 살펴보았으며 최적설계를 위한 여러 가지 요소들을 고찰하여 보았다.
