• Journal of the Korean Applied Science and Technology
• /
• v.35 no.4
• /
• pp.1073-1080
• /
• 2018

There are several types of petroleum products used for the fuel oil, according to their respective quality standards, grades and usage. Depending on the degree of oil tax rate by country, even the same petroleum products will have price gap. The illegal mixing of cheap petroleum products, which are subject to the lower tax rate, with relatively expensive transportation fuel causes problems such as tax evasion, environmental pollution and vehicle breakdown. In order to prevent illicit production and mixing of these different petroleum products, a small amount of markers are legally added to specific petroleum products. In Korea, markers are introduced and used to prevent illegal activity that kerosene used as fuel for house and commercial boiler are mixed with automotive diesel fuels, and marker contents are analyzed to use UV-Vis spectrophotometer and high performance liquid chromatography (HPLC). In this study, we have developed a method to qualitatively and quantitatively determine the marker added to petroleum products by gas chromatography-mass spectrometry (GC-MS) without adding developing reagent or sample pre-treatments.

• Applied Chemistry for Engineering
• /
• v.21 no.5
• /
• pp.542-547
• /
• 2010

n-Paraffin and saturated fatty acid methyl esters in the diesel and bio-diesel fuel crystallize at low temperature. Many articles have addressed various solutions for the low temperature crystallization problem and one of them is the use of methacrylate copolymers. In this work, we synthesized a series of copolymers in the reaction condition of 70 : 30 molar ratio of lauryl methacrylate (LMA) (or stearyl methacrylate (SMA)) and alkyl methacrylates. The structures of the copolymers were characterized by $^1H$-NMR and FT-IR spectroscopy, and the molecular weight of copolymers were obtained from Gel Permeation Chromatography (GPC) method. The concentrations of additives were 500~1000 ppm and 1000~10000 ppm in diesel fuels and bio-diesel fuel (BD5 and BD20), respectively. The addition of copolymers changes the many properties of fuel such as the pour point (PP), cloud point (CP) and cold filtering plugging point (CFPP). For example, the low temperature properties of the copolymers containing SMA ($PSMAmR_2n$) were excellently improved about 15, 7, and $10^{\circ}C$ for PP, CP and CFPP, respectively.

• Applied Chemistry for Engineering
• /
• v.23 no.2
• /
• pp.232-240
• /
• 2012

Bio-diesel (BD) is the mono alkyl esters of long chain fatty acids derived from renewable feed stocks like vegetable oils or animal fats. Bio-diesel shows poorer fuel properties than that of diesel fuel in a cold condition. For the diesel fuel, many cold flow improvers have been developed; however, since primary ingredients of bio-diesel are different from those of the diesel fuel, there is a limit to the cold flow improvement when the same cold flow improvers are added to bio diesel. In this study, to improve low temperature properties of bio-diesel, we developed a cold flow improver using an alkyl methacrylate monomer, prepared via ester reaction, and maleic anhydride and also conducted a ring opening reaction using amine. We characterized the products using $^1H-NMR$, FT-IR and GPC methods. In addition, the cold flow improvements of the products in Soybean BD and Palm BD in the concentration rage of 1000~10000 ppm were investigated. It was found that the addition of LMA2SMA6MA2-C8A in Soybean BD improved the pour point by $12.5\;^{\circ}C$.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2000.11a
• /
• pp.30-30
• /
• 2000

일반적인 소형 고체로켓의 모터 내에는 연료 첨가제로써 알루미늄이 함유되는데, 연소 시 산화된 이 성분은 액적 상태로 이동하여 노즐부내에 이상유동장을 형성시킨다. 이러한 산화알루미늄입자는 노즐벽면에 충돌, 점착하여 기계적, 열적 에너지전달을 일으키며 노즐벽면의 삭마를 유발시키는 한편, 가스유동과의 속도 차, 온도차로 인해 저항요소로 작용하면서 노즐의 추력 성능 손실에 간접, 직접적인 원인이 된다.(중략)

• Journal of Hydrogen and New Energy
• /
• v.13 no.2
• /
• pp.135-142
• /
• 2002

본 연구는 Chemical hydride 형태의 수소발생제를 포함한 액체연료를 이용한 신개념의 알칼라인 연료전지의 특성을 분석하였다. Chemical hydride는 연료전지의 수소공급원으로써 사용될 수 있으며, 본 연구팀은 KOH 전해질에 수소발생제인 Sodium Borohydride ($NaBH_4$)를 첨가하여 제조된 액체연료를 알칼라인 연료전지에 공급함으서 상온에서 매운 우수한 전기 화학적 성능결과를 얻을 수 있었다. 이때 음극 찰물질로 $ZrCr_{0.8}Ni_{1.2}$ 수소저장합금이 사용되었으며, 양극은 방수처리된 카본지 위에 분산된 Pt/C 가 사용되었고, air가 latm으로 양극에 공급되었다. 음극에 대한 XRD 분석결과 음극에서의 산화에 의해 Sodium Borohydride ($NaBH_4$)가 분해되어 수소가 발생되며, 연속적으로 액체연료가 주입되어도 전지가 작동하는 것을 확인할 수 있었다. 이때 에너지밀도는 6,000 Ah/kg (for $NaBH_4$ or $KBH_4$)이다.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.05a
• /
• pp.90.1-90.1
• /
• 2011

연료전지 분리판은 연료, 공기, 수분이 흐를 수 있는 채널들이 포함되어 있으며, 전지들에 의해서 생산되는 전류를 흐르게 할 수 있는 전기전도성을 가져야 할 필요가 있다. 일반적인 금속판들은 연료전지 스택 내의 산성 분위기에 존재해야 하기 때문에 표면 부식이 쉽게 발생한다. 그라핀(graphene)은 우수한 전기전도성을 가지고 있을뿐만 아니라 물리화학적 내식성 및 내구성을 가지고 있어 연료전지 분리판으로서 응용이 가능할 것으로 판단된다. 본 연구에서는 일반적으로 널리 사용하고 있는 스테인리스강(stainless steel)을 모재로 사용하였으며, 그라핀을 전기분무법(electro spray coating)으로 코팅하여 스테인리스강의 내식성 및 전기전도성을 동시에 향상시키고자 하였다. 그라핀은 에탄올을 용매로 사용하여 분산하였으며, 분산제로 소량의 다이페닐다이에톡시실란(diphenyldiethoxysilane)을 첨가하여 코팅용액을 제작하였다. 코팅공정은 15kV 전압을 가하여 1시간동안 코팅을 진해하였으며, 그라핀-스테인리스강 모재의 미세구조를 전자현미경과 광학현미경을 통하여 관찰하였다. 또한 X-선 회절분석법을 이용하여 그라핀의 결정구조를 분석하였다. 한편 스택의 내부와 유사한 산화성 분위를 모사하기 위해 $80^{\circ}C$의 0.1N $H_2SO_4+2ppm\;F^-$ 용액에서 내식성 실험을 수행하였고, 면간접촉저항도 측정하였다. 그라핀이 코팅된 스테인리스강 시편은 고분자전해질 연료전지 분리판의 요구조건을 만족하였으며, 연료전지 분리판으로서의 적용가능성을 확인하였다.

• Applied Chemistry for Engineering
• /
• v.8 no.4
• /
• pp.640-644
• /
• 1997

We investigated that how both the type and the concentration of coal and the surfactant and the electrolyte added to increase the fluidity of CWM influence rheological characteristics. According to the type of coal, the viscosity of CWM was increased with increasing O/C ratio. Also, the CWM was represented the property of non-Newtonian fluid, having yield stress which was linerarly increased with increasing coal concentration. According to the surfactant used as an additive, the rheological characteristics of CWM was represented the pseudoplastic property as n<1 without relating to the concentration of added surfactants. Also, according to the increase of the amount of electrolyte, n was nearly approached 1. Therfore, we found that CWM opproched Newtonian fluid and that when more than 0.05wt.% of electrolyte were added, yield stress was not shown up.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 1995.11a
• /
• pp.38-41
• /
• 1995

화석연료의 연소에 의하여 방출되는 SO$_2$ 와 NO 에 의한 대기오염의 심각성은 이미 잘 알려져 있으며 그에 따른 배출규제 또한 강화되고 있다. 최근에는 탈황과 탈질을 동시에 처리하는 동시 탈황탈질 공정의 연구가 진행되고 있다. 동시제거 공정은 주로 흡수제/촉매를 토대로 개발되고 있으며 산화구리가 담지된 알루미나 (CuO/${\gamma}$-A1$_2$O$_3$) 흡수제/촉매는 SOx, NOx 동시제거에 효과적인 물질로 알려져 있다. 담지된 CuO 와 담체 A1$_2$O$_3$는 SO$_2$ 와 $O_2$ 존재하에 반응하여 CuSO$_4$ 와 $Al_2$(SO$_4$)$_3$ 가되며 [1] CuSO$_4$ 와 미반응된 CuO 는 NO 제거를 위한 촉매로서의 역할을 하게 된다 [2].

• Journal of Advanced Marine Engineering and Technology
• /
• v.38 no.9
• /
• pp.1045-1050
• /
• 2014

$N_2O$(Nitrous Oxide) is known as the third major GHG(Green House Gas) following $CO_2$(Carbon Oxide) and $CH_4$(Methane). The GWP(Global Warming Potential) factor of $N_2O$ is 310 times as large as that of $CO_2$ because $N_2O$ in the atmosphere is very stable, and it becomes a source of secondary contamination after photo-degradation in the stratosphere. Investigation on the cause of the $N_2O$ formation have been continuously reported by several researchers on power sources with continuous combustion form, such as a boiler. However, in the diesel engine, research on $N_2O$ generation which has effected from fuel components has not been conducted. Therefore, in this research, author has investigated about $N_2O$ emission rates which was changed by nitrogen and sulfur concentration in fuel on the diesel engine. The test engine was a 4-stroke direct injection diesel engine with maximum output of 12 kW at 2600rpm, and operating condition of that was set up at a 75% load. Nitrogen and sulfur concentrations in fuel were raised by using six additives : nitrogen additives were Pyridine, Indole, Quinoline, Pyrrol and Propionitrile and sulfur additive was Di-tert-butyl-disulfide. In conclusion, diesel fuels containing nitrogen elements less than 0.5% did not affect $N_2O$ emissions in the all concentrations and kinds of the additive agent in the fuel. However, increasing of the sulfur additive in fuel increased $N_2O$ emission in exhaust gas.

• Journal of Korea Foresty Energy
• /
• v.21 no.3
• /
• pp.59-65
• /
• 2002

Recently, densified fuels from biomass are widely used North America and Europe as a regenerable and clean bioenergy. Compaction of sawdust of poplars(Populus tomentiglandulosa and Populus davidiana) with starch glue for densified fuel were studied. Calorific and elemental analysis were carried out to assess these species as fuel. Hot-press process was used and compaction was performed under temperatures from 120 to $160^{\circ}C$ and at pressure of 50kgf/$cm^2$ for prescribed time. Densified fuels were evaluated by its specific gravities, compressive strengths and fines. In the case of with-glue system, when the press temperature is $160^{\circ}C$ and press time is above 7.5 minutes, densified fuels with fines less than 5% can be produced. On the contrary, in the case of without-glue system, densified fuels with fines less than 5% can be produced by controlling the press conditions and the moisture content of sawdust.