Development of an automated transesterification reactor controller using refractive index to detect end point of reaction

• Main Author: Co, Dana Mae S.
• Format: text
• Language: English
• Published: Animo Repository 2015
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4958
• Institution: De La Salle University

Refractive index is a physical property which can be used in determining the end point of transesterification in producing biodiesel. The traditional method in acquiring refractive index measurements takes place outside of a transesterification reactor making remote sensing impossible. Biodiesel manufacturers subjectivity and rigorous methods in experimentally identifying the end point of the reaction causes large scale production complicated. In this study, a fiber optic sensor is used to identify the appropriate wavelength to use in obtaining changes in intensity as the basis for acquiring the refractive index measurement of the sample as well as fuzzy logic in determining the end point of transesterification. The different components are used to address real time data acquisition and processing in controlling the continuation or termination of the reaction. A developed transesterification reactor controller consisting of fiber optic sensor using near infrared spectroscopy to attain refractive index and fuzzy logic control using proportional and derivative errors as its inputs to effectively detect the reaction end point while in progress in real time. It showed that the transesterification reaction of refined, bleached, deodorized coconut oil and methanol using 1:6 molar ratio and 0.003 (by weight of oil) of sodium hydroxide was at a range of 72 minutes to 92 minutes and the percent error compared with measurements from traditional refractometer was less than 0.24%. In doing so, an online system for real time data acquisition and processing was established. By adapting the developed system in a manufacturing setup, it will entail changes in the reactors such as the use of light and fiber optic but will enhance sampling and testing efficiency. The study provides an alternative way to automatically identify the end point of transesterification and successfully presents a method for remote sensing identifying the reaction termination timely to the mixture condition.