• Journal of the Korean Society of Safety
• /
• v.24 no.5
• /
• pp.13-20
• /
• 2009

The risk assessment of thermal hazard to identify chemical or process hazard during early process developments have been considered. The early identification of thermal hazards associated with a process, such as rapid heats of reaction, exothermic decompositions, and the potential for thermal runaways before any large scale operations are undertaken. This paper presents to evaluate the safe operating parameters/envelope for exist plant operations. The assessment of thermal hazard with operating conditions such as amount of process materials, inhibitor, and catalyst on esterification process in manufacture of concrete mixture agents are described. The experiments were performed by a sort of calorimetry with the Multimax reactor system as a screening tool. The aim of the study was to evaluate the thermal risk of process material and mixture in terms of safety security to be practical applications in esterification process. It suggested that we should provide the thermal hazard of reaction materials to present safe operating conditions with cause of accident through this study.

• Journal of the Korean Society of Safety
• /
• v.24 no.4
• /
• pp.40-46
• /
• 2009

The early identification of thermal hazards associated with a process such as the heats of reaction, exothermic decompositions, and the understanding of thermodynamics before any large scale operations are undertaken. The evaluation of reaction factors and thermal behavior on esterification process in manufacture of concrete mixture agents are described in the present paper. The experiments were performed in the differential scanning calorimetry(DSC), C 80 calorimeter, and thermal screening unit($TS^u$). The aim of the study was to evaluate the thermal stability of single material and mixture in esterification process. We provided the thermal data of chemical materials to present safe operating conditions through this study.

• Applied Chemistry for Engineering
• /
• v.24 no.1
• /
• pp.72-76
• /
• 2013

In this study, the boric acid which is a by-product in the esterification process to obtain norbornene diester derivatives was recovered, and then its reusability for esterification of norbornene was investigated. Four types of trialkyl borate (tributyl borate, tripentyl borate, and triisopentyl borate, trihexyl borate) were synthesized through the esterification with boric acid and four types of alcohol. Then, diester derivatives were synthesized by esterification with the synthesized trialkyl borate and norbornene dicarboxylic acid. The conversion of norbornene dicarboxylic acid is 89.50~99.31%. The boric acid which is a by-product in the esterification were recovered with NaCl salt and used for synthesizing trialkyl borate. The recovery rate was 92.43~99.35 %. When the recovered trialkyl borate was used in esterification, there are little losses of the yield. Since boric acid which is a major by-product is able to be recovered, the process is expected to be a clean technology to prevent an environmental pollution by the emission of chemical compounds.

• Membrane and Water Treatment
• /
• v.7 no.2
• /
• pp.143-154
• /
• 2016

Acetic acid can be removed from wastewater by esterification in a membrane reactor. Pervaporation membrane reactor (PVMR) is an alternative process to conventional separation processes. It is an environmentally friendly process. The main advantages of the PVMR are simultaneous water removal and production of an ester economically. In this study, the synthetic wastewater has been used. Esterification reaction of acetic acid with isopropanol has been studied in the presence of tungstosilicic acid hydrate as a catalyst in a batch reactor and in a PVMR. The effects of important operating parameters such as reaction temperature, initial molar ratio of isopropanol to acetic acid and catalyst concentration has been examined. Removal of acetic acid (conversion of acetic acid) was obtained as 85% using a PVMR by removal of water from the reaction mixture.

• Journal of ILASS-Korea
• /
• v.14 no.3
• /
• pp.117-121
• /
• 2009

Biodiesel fuel has different spray patterns, because viscosity and surface tension of biodiesel fuel are higher than that of diesel fuel. The diesel combustion is strongly controlled by the fuel spray behavior in combustion chamber. So, it was needed to understand the spay characteristics of non-esterification biodiesel fuel. In this study, the spray characteristics of non-esterification biodiesel fuel was investigated to confirm of an effect of WDP. The characteristics of fuel atomization was analyzed with SMD and span factor through laser diffraction particle analyzer (LDPA), and the process of spray injection was visualized through the visualization system composed of a halogen lamp and high speed camera. It was found that injection delay time and SMD of blended fuel with WDP get shoter and smaller than that of non-esterification biodiesel fuel.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10a
• /
• pp.582-588
• /
• 1993

A scheme of dynamic optimization for batch reactor his been developed and applied to a semi-batch esterification reactor. To obtain optimal operating conditions for the given semi-batch reactor system with complex reaction kinetic and process constraints, a general nonlinear programming solver and finite element techniques have been introduced. The optimization results for the complex reactor system have been compared with those of Kumar et al. [1984] to show better optimization performance. The proposed optimizing scheme has been applied to the free end time problem to obtain the realistic operating condition. The results can supply valuable information for economic operation of the given batch esterification reactor.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.5 no.3
• /
• pp.196-201
• /
• 2000

Lactic acid is of interest as the raw materials of polyactide that is a biodegradable polymer. For an effective purification of acid, batch distillation with the simultaneous reactions was used. Two Oldershow colums and reboilers were usde for fractionation of methanol and reactions. Two Oldershaw columns and reboilers were used for fractionation of methanol and reactions. Esterification reaction of lactic with methanol produced methyllactate and water. The productes of the esterification reaction, methl lactate and water were transported to the reboiler of the reproysis part. In hydroduced in the hydrolysis part and nureacter method lactic acid and methanol. Methanol produced in the hydroysis part and unreacted method lactic acid and methanol in the esterification part were separated by distillation and recycled to the revoiler of the esterification part so that the esterification reaction would be stimulated. Thus, pure lactic acid solution remained in the reboiler of the hydroysis part. The effect of the number of stages in column on the recovery yield was also inverstigated. In the operation with colums improved the fractionation of componets and stimulated the reactions in two parts.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.11
• /
• pp.3410-3414
• /
• 2013

Atom-economical esterification is of great importance in green chemistry. In this work, we demonstrated the catalyst and additive free esterification of alcohols by their reaction with 2-acyl-4,5-dichloropyridazin-3(2H)-ones without solvent at $100^{\circ}C$. Aliphatic and aromatic alcohols were converted into the corresponding esters in good to excellent yields. It is noteworthy that the reaction is solvent-free, atom-economic, easy-workup, and rapid and that the process is inexpensive.

• Applied Chemistry for Engineering
• /
• v.20 no.5
• /
• pp.532-535
• /
• 2009

In this study, the fatty acid methyl ester was prepared from the vegetable oil by inducing ultrasound energy. The ultrasound energy was applied to the esterification reaction for heating and stirring effects. Ultrasonic induction results in the shortened reaction time and brings the increase of the methyl ester yield. However, the continuous introduction of ultrasound during the esterification reaction results in temperature increase, then the over-heating of reaction temperature was ineffective. Therefore, the system temperature was controlled at constant temperature state with the cooling circulation. The ultrasound induction reaction had the fatty acid methyl ester yield of 93% at the reaction time was 30 minutes, faster than the traditional esterification process.

• Journal of Institute of Control, Robotics and Systems
• /
• v.11 no.6
• /
• pp.550-557
• /
• 2005

The multivariate statistical analysis methods, using both multiple linear regression(MLR) and partial least square(PLS), have been applied to predict the reactor properties and the product quality of a direct esterification reactor for polyethylene terephthalate(PET) synthesis. On the basis of the set of data including the flow rate of water vapor, the flow rate of EG vapor, the concentration of acid end groups of a product and other operating conditions such as temperature, pressure, reaction times and feed monomer mole ratio, two multi-variable analysis methods have been applied. Their regression and prediction abilities also have been compared. The prediction results are critically compared with the actual plant data and the other mathematical model based results in reliability. This paper shows that PLS method approach can be used for the reasonably accurate prediction of a product quality of a direct esterification reactor in PET synthesis process.