ISSN : 1225-0112(Print)
ISSN : 2288-4505(Online)
ISSN : 2288-4505(Online)
Applied Chemistry for Engineering Vol.28 No.5 pp.559-564
DOI : https://doi.org/10.14478/ace.2017.1075
DOI : https://doi.org/10.14478/ace.2017.1075
Optimization of Waste Cooking Oil-based Biodiesel Production Process
Using Central Composite Design Model
Abstract
In this study, the optimization process was carried out by using the central composite model of the response surface methodology in waste cooking oil based biodiesel production process. The acid value, reaction time, reaction temperature, methanol/ oil molar ratio, and catalyst amount were selected process variables. The response was evaluated by measuring the FAME content (more than 96.5%) and kinematic viscosity (1.9~5.5 cSt). Through basic experiments, the range of optimum operation variables for the central composite model, such as reaction time, reaction temperature and methanol/oil molar ratio, were set as between 45 and 60 min, between 50 and 60 ℃, and between 8 and 12, respectively. The optimum operation variables, such as biodiesel production reaction time, temperature, and methanol/oil molar ratio deduced from the central composite model were 55.2 min, 57.5 ℃, and 10, respectively. With those conditions the results deduced from modeling were as followings: the predicted FAME content of the biodiesel and the kinematic viscosity of 97.5% and 2.40 cSt, respectively. We obtained experimental results with deduced operating variables mentioned above as followings: the FAME content and kinematic viscosity of 97.7% and 2.41 cSt, respectively. Error rates for the FAME content and kinematic viscosity were 0.23 and 0.29%, respectively. Therefore, the low error rate could be obtained when the central composite model among surface reaction methods was applied to the optimized production process of waste cooking oil raw material biodiesel.
중심합성계획모델을 이용한 폐식용유 원료 바이오디젤 제조공정의 최적화
초록
본 연구에서는 폐식용유를 이용한 바이오디젤 제조공정에 반응표면분석법 중 중심합성계획모델을 이용하여 최적화 과정을 수행하였다. 공정변수로는 폐식용유의 산가, 반응시간, 반응온도, 메탄올/유지 몰비, 촉매량 등을 선택하였고, 반응치로는 FAME 함량(96.5% 이상) 및 동점도(1.9~5.5 cSt)를 설정하였다. 기초실험을 통해 계량인자범위를 반응시간 (45~60 min), 반응온도(50~60 ℃), 메탄올/유지 몰비(8~12)로 정하고, 중심합성계획모델을 이용한 최적화 결과 바이오 디젤의 제조공정의 최적조건은 반응시간 55.2 min, 반응온도 57.5 ℃, 메탄올/유지 몰비 10으로 나타났다. 이 조건에서 바이오디젤의 예측 FAME 함량은 97.5%, 동점도는 2.40 cSt이었으며, 실제 실험을 통해 확인한 결과 FAME 함량 (97.7%), 동점도(2.41 cSt)로 측정되어 오차율은 각각 0.23, 0.29%로 나타났다. 따라서 폐식용유 원료 바이오디젤 제조 공정 최적화 과정에 반응표면분석법 중 중심합성계획모델을 적용할 경우 매우 낮은 오차율을 얻을 수 있었다.