• Journal of the Korean Chemical Society
• /
• v.5 no.1
• /
• pp.52-55
• /
• 1961

Assuming an intramolecular hydrogen-bonding, computation has been made on the optical rotatory power of 2-Chloro-1-Propanol. The magnitude of the calculated rotation is in fair agreement with the measured value of Lucas (calculated value: 21.6. measured value: 17.39). The agreement supports the validity of the assumption concerning the hydrogen-bonding between O atom and Cl atom. The agreement in sign confirms the validity the Fischer projection formula given by Lucas.

• Journal of the Korean Chemical Society
• /
• v.10 no.3
• /
• pp.119-128
• /
• 1966

The glass electrode was empirically calibrated in methanol-and 2-propanol-water mixed solvents, by means of which the pH-meter reading could be converted to stoichiometric hydrogen ion concentration. The thermodynamic dissociation constants of hydrogen cupferrate in methanol-and 2-propanol-water solution were potentiometrically determined with the changes in composition of organic solvents at 0.01 and 0.05 of the ionic strength and 25$^{\circ}C$. The empirical formula of the constants with mole fraction (n) of the organic solvent are as follow: methanol-water solution $pK_a$= 2.24n + 4.29 at ${\mu}$ = 0.01 n = 0.0476∼0.642 $pK_a$ = 2.35n + 4.38 at ${\mu}$ = 0.05 n= 0.0446~0.642 2-propanol-water solution $pK_a$= 5.50n + 4.48 at ${\mu}$ = 0.05 n = 0.0253~0.259 The relationships between $pK_a$ of acetic acid, propionic acid and HCup and dielectric constant of some mixed solvents were discussed. It would be considered that the factors effecting $pK_a$ value of weak acid in mixed-solvent are not only dielectric constants but acid-base character and solvation effect of the solvent, etc.

• Journal of the Korean Society of Safety
• /
• v.32 no.2
• /
• pp.66-71
• /
• 2017

The autoignition temperature (AIT) is crucial combustible characteristics which need attention in chemical process that handle hazardous materials. The AIT, also to as minimum spontaneous ignition temperature(MSIT), is the lowest temperature of a hot surface at which the substance will spontaneously ignite without any obvious sources of ignition such as a spark or flame. The AIT may be used as combustion property to specify operating, storage, and materials handling procedures for process safety. This study measured the AITs of n-propanol+acetic acid system from ignition delay time(time lag) by using ASTM E659 apparatus. The AITs of n-propanol and acetic acid which constituted binary system were $435^{\circ}C$ and $212^{\circ}C$, respectively. The experimental AITs of n-propanol+acetic acid system were a good agreement with the calculated AITs by the proposed equations with a few A.A.D.(average absolute deviation). In the case of n-propanol and acetic acid system, the minimum autoignition temperature behavior (MAITB), which is lower than the lower AIT, is shown among the two pure substances constituting the mixture.

• Journal of the Korean Society of Safety
• /
• v.34 no.1
• /
• pp.34-39
• /
• 2019

Flash point is the important indicator to determine fire and explosion hazards of liquid solutions. In this study, flash points of n-propanol+n-hexanol and n-butanol+n-hexanol systems were obtained by Seta flash tester. The methods based on UNIFAC equation and multiple regression analysis were used to calculate flash point. The calculated flash point was compared with the experimental flash point. Absolute average errors of flash points calculated by UNIFAC equation are $2.9^{\circ}C$ and $0.6^{\circ}C$ for n-propanol+n-hexanol and n-butanol+n-hexanol, respectively. Absolute average errors of flash points calculated by multiple regression analysis are $0.5^{\circ}C$ and $0.2^{\circ}C$ for n-propanol+ n-hexanol and n-butanol+n-hexanol, respectively. As can be seen from AAE, the values calculated by multiple regression analysis are noticed to be better than the values by the method based on UNIFAC eauation.

• Clean Technology
• /
• v.25 no.2
• /
• pp.140-146
• /
• 2019

Flammable substances, such as organic solvents, are commonly used in laboratories and industrial processes. The flash point of flammable liquid mixtures is a very important parameter for characterizing the ignition and explosion hazards, and the flash points of mixtures of $C_2{\sim}C_3$ alcohols and 2,2,4-trimethylpentane were measured in the present study. The 2,2,4-trimethylpentane is an important component of gasoline and is frequently used in the petroleum industry as a solvent. Lower flash point data were measured for the binary systems {ethanol + 2,2,4-trimethylpentane}, {1-propanol + 2,2,4-trimethylpentane}, and {2-propanol + 2,2,4-trimethylpentane}. The flash point measurements were carried out according to the standard test method (ASTM D3278) using a Stanhope-Seta closed cup flash point tester. The measured flash points were compared with the predicted values calculated using Raoult's law and also following $G^E$ models: Wilson, Non-Random Two Liquid (NRTL) and UNIversal QUAsiChemical (UNIQUAC). These models were able to predict the experimental flash points for different compositions of {$C_2{\sim}C_3$ alcohols + 2,2,4-trimethylpentane} mixtures with minimal deviations. The average absolute deviation between the predicted and measured lower flash point was less than 1.28 K. A minimum flash point behaviour was observed in all of the systems as in the many observed cases for the hydrocarbon and alcohol mixtures.

• Journal of the Korean Institute of Gas
• /
• v.19 no.3
• /
• pp.18-24
• /
• 2015

The flash point is one of the most important indicators of the flammabiliy of liquid solutions. The flash point is the lowest temperature at which there is enough concentration of flammable vapor to form an ignitable mixture with air. In this study the flash points of binary flammable solutions, 2-propanol+propionic acid and n-hexanol+formic acid systems, were measured using Seta flash closed cup tester. Particularly n-hexanol+formic acid system exhibited minimum flash point behavior. The measured values were compared with the calculated values using Raoult's law and optimization method. The calculated data by optimization method described the measured values more effectively than those calculated by Raoult's law.

• Journal of Sensor Science and Technology
• /
• v.31 no.5
• /
• pp.343-347
• /
• 2022

Recently, the problem of global warming caused by greenhouse gases is getting serious due to the development of industry and the increase in transportation means. Accordingly, the need for a technology to reduce carbon dioxide, which accounts for most of the greenhouse gas, is increasing. Among them, a catalyst for converting carbon dioxide into fuel is being actively studied. Catalysts for reducing carbon dioxide are classified into thermal catalysts and photocatalysts. In particular, the photocatalyst has the advantage that carbon dioxide can be reduced only by irradiating ultraviolet rays at room temperature without high temperature or additional gas. TiO₂ is widely used as a photocatalyst because it is non-toxic and has high stability, but has a disadvantage of low carbon dioxide reduction efficiency. To increase the reduction efficiency, 1-propanol was used in the synthesis process. This prevents agglomeration of the catalyst and increases the specific surface area and pores of TiO₂, thereby increasing the surface area in contact with carbon dioxide. As a result of measuring the CO₂ reduction efficiency, it was confirmed that the efficiency of TiO₂ with 1-propanol and TiO₂ without 1-propanol was 19% and 12.3%, respectively, and the former showed a 1.5 times improved efficiency.

• Journal of the Korea Society for Simulation
• /
• v.5 no.1
• /
• pp.43-50
• /
• 1996

2-propanol/acetone/hydrogen 반응계로 구성된 화학적 열펌프 시스템은 낮은 온도(82.5~$90^{\circ}C$)에서의 2-propanol의 탈수소화 반응과 높은 온도(약 $200^{\circ}C$ 부근)에서의 acetone의 수소화반응을 이용하여 열을 고품위화 시키는 장치이다. 본 연구에서는 이 시스템의 해석 및 설계를 목적으로 이 시스템에 대한 수치적인 모델들을 세우고 Sequential modular approach를 이용하여 시스템의 모사를 수행하였다. 또한 에너지 효율을 최대화하기 위하여 열펌프 시스템에서의 환류비의 영향을 규명하였다. 모사결과 이 시스템의 scale up을 위한 정량적인 정상상태 운전조건들을 구할수 있었으며 두 반응의 반응 전화율이 다르더라도 반응물의 유량의 차이를 통하여 두 반응열이 거의 같아지는 것을 알수 있었다. 아울러 주어진 운전조건에서 증류의 환류비는 최소환류비 근처의 최적값이 존재함을 알수 있었다.

• Journal of Life Science
• /
• v.22 no.3
• /
• pp.417-427
• /
• 2012

We compared the transcriptome in response to propanol stress in wild-type and propanol-resistant mutant Escherichia coli using the DNA microarray technique. The correlation value of RNA expression between the propanol-treated wild type and the untreated-one was about 0.949, and 50 genes were differentially expressed by more than twofold in both samples. The correlation value of RNA expression between the propanol-treated mutant and the untreated one was about 0.951, and 71 genes in two samples showed differential expression patterns. However, the values between the wild type and mutant, regardless of propanol addition, were 0.974-0.992 and only 1-2 genes were differentially expressed in the two strains. The representative characteristics among differentially expressed genes in W3110 or P19 treated with propanol compared to untreated samples were up-regulation of hest shock response genes and down-regulation of genes relating to ribosome biosynthesis. In addition, many genes were regulated by transcription regulation factors such as ArcA, CRP, FNR, H-NS, GatR, or PurR and overexpressed by sigma factor RpoH. We confirmed that RpoH mediated an important host defense function in propanol stress in E. coli W3110 and P19 by comparison of cell growth rate among the wild type, rpoH disruptant mutant, and rpoH-complemented strain.

• Fire Science and Engineering
• /
• v.24 no.2
• /
• pp.172-177
• /
• 2010

The values of the AIT (autoignition temperature) for fire and explosion protection are normally the lowest reported. The MAITB (Minimum Autoignition Temperature Behavior) of flammable liquid mixture is exhibited when the AITs of mixture is below the AIT of the individual components. The MAITB is an interesting experimental features, which can be significant from the perspective of industrial fire safety. In this study, the AITs of toluene + iso-propanol(IPA) and p-xylene + n-butanol systems were measured using ASTM E659-78 apparatus. The AITs of toluene, iso-propanol (IPA), pxylene and n-butanol which constituted two binary systems were $547^{\circ}C,\;463^{\circ}C,\;557^{\circ}C$ and $340^{\circ}C$ respectively. The toluene + iso-propanol(IPA) system is exhibited MAITB at 0.3 mole fraction of toluene, and its minimum autoignition temperature was $460^{\circ}C$.