Oxidation of biodiesel (BD) obtained from the decomposition of biomass can damage the fuel injection and engine parts during its use as a fuel. The excess heating of vegetable oils can also cause polymerization of the biodiesel. The extent of BD oxidation depends on its fatty acid composition. In this study, an accelerated oxidation test of BDs at 95 • C was investigated according to ASTM D 2274 by applying a long-term storage test for 16 weeks. The density, viscosity, and total acid number (TAN) of BDs increased because of the accelerated oxidation. Furthermore, the contents of unsaturated fatty acid methyl esters (FAMEs), C18:2 ME, and C18:3 ME in BDs decreased due to the accelerated oxidation. The 1 H-nuclear magnetic resonance spectrum of BDs that were obtained from the accelerated high temperature oxidation at 180 • C for 72 h differed from that of fresh BDs. The mass spectrum obtained from the analysis of the model FAME, linoleic acid (C18:2) methyl ester, which was oxidized at high temperature, indicated the formation of dimers and epoxy dimers of linoleic acid (C18:2) methyl ester by a Diels-Alder reaction.

No abstract

− Gasoline generates organic acid and polymer (gum) by hydrocarbon oxidation depending on the storage environment such as temperature and exposure to sunlight, which can cause metal corrosion, rubber and resin degradation and vehicle malfunction caused by accumulation in fuel supply system. The gasoline which has not been used for a long time in bi-fuel (LPG-Gasoline) vehicle causes problems, and low octane number gasoline have evaporated into the field, but the exact cause has not been studied yet. In this study, we suggest a plan of quality management by investigating the gasoline oxidation behavior. In order to investigate the oxidation behavior of gasoline, changes of gasoline properties were analyzed at various storage conditions such as storage time, storage vessel type (vehicle fuel tank, PE vessel and Fe vessel) and storage circumstances (sunlight exposure and open system, etc.). Currently distributing gasoline and bioethanol blended fuel (blended 10%) were stored for 18 weeks in summer season. The sample stored in PE vessel was out of quality standard (octane number, vapor pressure, etc.) due to the evaporation of the high octane number and low boiling point components through the vessel cap and surface. Especially, the sunlight exposure sample stored in PE vessel showed rapid decrease of vapor pressure and increase of gum. Bioethanol blended fuel showed similar results as gasoline.

요약 일반적으로 황분계 부취제는 연료가스에 인한 가스중독 발화 폭발 등의 사고를 방지하고 배출가 , , , 스에 의해 연료 가스 누출의 즉각적으로 손쉽게 검출할 수 있도록 그리고 도시가스와 LPG, LNG 같은 연료가스에 첨가 사용하고 있다 본 연구에서는 새로운 비황분계 부취제 를 사용 . (K-Petro S-Free) 한 혼합연료의 엔진 성능과 배출가스 LPG (CO, THC, CO 2 , NO x , SO 2 특성을 살펴보았다 새로운 ) . 비황분계 부취제를 를 혼합한 연료 여름용 겨울용 와 현재 사용 중인 황분계 부취제 40mg/kg LPG ( , ) 를 혼합한 연료의 엔진 성능과 배출가스 특성을 실험하였다 비황분계 (EM, ethyl mercaptan) LPG . 부취제를 혼합한 연료의 엔진 성능은 황분계 부취제를 혼합한 연료와 비교할 때 비슷한 LPG LPG 결과를 보여 주었다 한편 비황분계 부취제를 혼합한 연료의 엔진 배출가스 중 . , LPG CO, THC, CO 2 , NO x 은 황분계 부취제를 혼합한 연료와 비교할 때 비슷한 특성을 보였다 그러나 에서 LPG . 2,000rpm 배출가스 중 SO 2 은 비황분계 부취제를 혼합한 연료가 황분계 부취제를 혼합한 연료보다 LPG LPG 감소하는 우수한 결과를 보였다 83% .주요어 : 비황분계 부취제 연료 배출가스 , LPG , Abstract -In general, odorants are added to fuel gases, such as LPG, LNG and city gas, to prevent gas poisoning, ignition, explosion, or other accident caused by fuel gases, and to enable immediate and easy detection of fuel-gas leakage by emitting an offensive smell. This study describes a study on the performance and exhaust emissions (CO, THC, CO 2 , NO x , SO 2 ) characteristics of liquefied petroleum gas (LPG) engine using LPG fuel with new sulfur free odorant (K-Petro S-Free). New sulfur free odorant (40 mg/kg) was added to 2 type LPG fuels for summer, and winter and it was used in performance and exhaust emissions, compare to LPG fuel with sulfur containing odorant (EM, ethyl mercaptan). Engine performance using LPG with sulfur free odorant was similar to LPG with sulfur-containing odorant. Exhaust emissions (CO, THC, CO 2 , NO x ) of LPG with sulfur free odorant were also similar characteristics, compare with sulfur containing odorant. Especially, SO 2 emission using LPG with K-Petro S-Free odorant was more reduced 83 % than LPG with sulfur containing odorant(EM) at 2000 rpm.

>> Recently, the Renewable Fuel Standard(RFS) has been commenced from July 31, 2015 in the New and Renewable Energy Act for expanding the supply of renewable energy and reduction of national GHG target in Korea. The biodiesel is only a means of implementation for the RFS, therefore the biodiesel supply expansion is important for fulfilling the RFS obligation policy. The major key points of the biodiesl supply are expanding domestic feedstocks due to the over 60% dependence on foreign feedstock and reducing the price of feedstock because of the over 70% occupation of feed stock price in the biodiesl production cost. Therefore, we estimated actual amount of potential feedstocks which are possible to use for biodiesl production in Korea and investigated technical and political improvements for expanding biodiesl. For estimating a potential feedstocks, first selected the potential biodiesl feedstocks by investigating the status of global biodiesl feedstocks and then analyzed the possible potential amount of each feedstock by surveying the generation situations, the distribution structures and the technical level.