• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.1
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• pp.39-48
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• 2009

Biodiesel is estimated to be the best recycling energy source as an alternative fuel for transportation vehicles which represents the biggest share of greenhouse effect gas exhausts. Thus, in order to widely expand use of biodiesel and to enhancement its reliability, studies on quality improvement of biodiesel is needed. In this study, we have produced biodiesel(BD100, BD20) through esterification reaction using raw material of waste frying oil and analyzed compatibility with 24 items of quality criteria. As waste frying oil has high contents of unsaturated fatty acid such as Oleic acid, Linoleic acid and Linolenic acid, it is confirmed that there is no problem in using the same as a raw material of biodiesel. The result of analyzing the quality criteria items of biodiesel showed that it satisfied all the quality criteria except the oxidation stability of BD100, which was 2 hours, fatty acid methyl ester of BD20, which was 18.6w% and the filter plugging point, which was $-5^{\circ}C$. We believe that it will contribute to improved utilization of waste resources as alternative energy if studies on technology to improve quality of some items are provided.

• The Korean Journal of Pesticide Science
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• v.9 no.2
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• pp.122-131
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• 2005

For development of new agrochemical fungicide, syntheses of pyrrolo[2,1-b]thiazole carboxanilide derivatives 9 and antifungal screening against 6 kinds of plant pathogens were carried out. Functionalization of carboxylic acid on C-2 into carboxanilide in the pyrrolo[2,1-b]thiazole resulted in new 20 candidates, in which are ${\alpha},{\beta}$-unsaturated carboxanilide and methyl groups that are in cis relationship. Treatment of acetoxy-1,4-thiazin with magnesium in refluxing methanol gave pyrrolo[2,1-b]thiazole ethyl ester 4 in higher yield than that of the previous report. Hydrolysis of this compound afforded the corresponding acid 5, which reacted with aniline derivatives in the presence of coupling reagent, DIC to give pyrrolo[2,1-b]thiazole carboxanilides 9. As the result of in vivo antifungal assay of 9 against rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew, some compounds showed selectively antifungal activities against the rice blast and wheat leaf rust.

• Korean Chemical Engineering Research
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• v.43 no.5
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• pp.621-626
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• 2005

The esterification reaction of free fatty acid with methanol was investigated in the presence of catalyst, Amberlyst-15, producing fatty acid methyl ester, namely, biodiesel. In this paper, the effects of the reaction parameters such as reaction temperature, mole ratio of alcohol to oleic acid and mass of catalyst on the catalytic activity have been examined. The results showed that the reaction rate increased about twice as the temperature increased every $20^{\circ}C$ in the reaction temperature range from 333 K to 373 K. The equilibrium conversion rate of oleic acid increased with the feed mole ratio of alcohol to acid ranging from 6:1 to 44:1. When the feed mole ratio was higher than 44:1, all the results were similar to that of 44:1. As for the influence of the mass of catalyst, the initial reaction rate increased from 1.2 to 1.3 times as the mass of catalyst doubles in the range of the catalyst weight from 5 to 20 wt%. The experiment data obtained were well described by the second reaction rate using a pseudo-homogeneous model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.6000-6007
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• 2013

Cr(VI)-heterocyclic complex[Cr(VI)-isoquinoline] was synthesized by the reaction between of heterocyclic compound(isoquinoline) and chromium trioxide, and characterized by IR and ICP analysis. The oxidation of benzyl alcohol using Cr(VI)-isoquinoline in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order : cyclohexene$CH_3$, m-Br, m-$NO_2$). Electron- donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant(${\rho}$) was -0.69(308K). The observed experimental data have been ratiolized. The hydride ion transfer causes the prior formation of a chromate ester in the rate-determining step.

• Journal of Adhesion and Interface
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• v.11 no.2
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• pp.41-49
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• 2010

Furan-containing epoxide monomers (8, 9) were designed and synthesized as carbon-neutral, environment-friendly adhesion material. Bicyclic skeleton were constructed using the Diels-Alder reaction of furan and methyl acrylate, both readily accessible starting material from a biomass via bio-refinery process. After reduction of ester functionality, resulting hydroxyl moieties were coupled to epichlorohydrin to provide the epoxy-functionalized furanic monomers (8, 9). The structure of new furanic monomers was confirmed by $^1H$ and $^{13}C$ NMR spectroscopy. As UV-curable monomers, basic properties such as UV curing time and the extent of UV curing were evaluated by photo DSC. Photo-curing shrinkages were measured by linear variable differential transformer transducer (LVDT) and the effect of molecular structure on shrinkage was considered. In addition, new synthetic compounds showed the shear strength over 3 MPa when they were photo-cured between polycarbonate plates, which indicates these compounds are feasible to use as photo-curable adhesive materials.

• Polymer(Korea)
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• v.36 no.4
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• pp.440-447
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• 2012

The branched copolyester was synthesized and its molecular weight, $T_g$, 1/2 method temperature ($T_{1/2}$) and rheological properties were characterized for the application of toner binder. The linear copolyester had low molecular weight and melt elasticity obtained by dimethylterephthalate (DMT), ethylene glycol (EG) and 2,2-bis(4-(2-hydroxypropoxy) phenyl)propane (HPP). The branched copolyesters prepared with various branching agents such as 2-(hydroxymethyl)-2-ethylpropane-1,3-diol (trimethylol propane, TMP), 2,2-bi(hydroxymethyl)-1,3-propanediol (pentaerythritol, PER), 1,2,4-benzenetricarboxylic anhydride (trimellitic anhydride, TMA) and glycerol to improve the physical properties of the linear copolyester. The effect of branching agents on the molecular weight and melt elasticity of the branched copolyester was examined. The branched copolyesters prepared by adding over 15 mol% of branching agent showed relatively high molecular weight and melt elasticity, and $T_{1/2}$ value of $140^{\circ}C$. Therefore, the highly branched copolyesters were deemed suitable as a hot-melt toner of laser print process.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.717-726
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• 2017

The current allowable cross-contamination level of fatty acid methyl esters (FAME) in aviation turbine fuel (AVTUR) is 50 mg/kg, due to that the presence of FAME in AVTUR can significantly impact the fuel supply system and jet engine. It has been difficult to analyze the level of FAME in AVTUR, since it is consisted of a lot of hydrocarbons. In this study, thus, a new method using multi-dimensional GC-MS (MDGC-MS) was proposed in order to determine the FAME level in AVTUR effectively. Applying to MDGC-MS with Deans switching system enabled us to detect and quantify the FAME with low carbon numbers such as those derived from coconut oil and palm kernel oil. The matrix effect of MDGC-MS method, which could shift the FAME peaks to slightly longer retention times, was reduced by 20 times compared with that of 1-dimensional GC-MS reference method. This developed method could be suitable for qualitative and quantitative analyses to determine the contamination level of trace FAME in AVTUR.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.762-767
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• 2009

In this study, the feasibility of using vegetable oil extracted from tropical crop seed as a biodiesel feedstock was investigated by producing biodiesel and analysing the quality parameters as a transport fuel. In order to produce biodiesel efficiently, two step reaction process(pre-treatment and transesterificaion) was required because the tropical crop oil have a high content of free fatty acids. To determine the suitable acid catalyst for the pre-esterification, three kinds of acid catalysts were tested and sulfuric acid was identified as the best catalyst. After constructing the experimental matrix based on RSM and analysing the statistical data, the optimal pre-treatment conditions were determined to be 26.7% of methanol and 0.982% of sulfuric acid. Trans-esterification experiments of the pre-esterified oil based on RSM were carried out, then discovered 1.24% of KOH catalyst and 22.76% of methanol as the optimal trans-esterification conditions. However, the quantity of KOH was higher than the previously established KOH concentration of our team. So, we carried out supplemental experiment to determine the quantity of catalyst and methanol. As a result, the optimal transesterification conditions were determined to be 0.8% of KOH and 16.13% of methanol. After trans-esterification of tropical crop oil, the produced biodiesel could meet the major quality standard specifications; 100.8% of FAME, 0.45 mgKOH/g of acid value, 0.00% of water, 0.04% of total glycerol, $4.041mm^2/s$ of kinematic viscosity(at $40^{\circ}C$).