POWER RATE LAW BASED CHEMICAL KINETICS AND THERMODYNAMIC MODELING OF AFRICAN PEAR SEED OIL CONSECUTIVE IRREVERSIBLE BASE METHANOLYSIS FOR BIODIESEL PRODUCTION

  • C. Esonye
  • O.D. Onukwuli
  • S.O. Momoh
Keywords: Kinetics; methanolysis; rate constants; activation energy; African pear seed oil; biodiesel

Abstract

Currently the major challenge of biodiesel application as a replacement to petrodiesel is its industrial production sustainability.Consequently, the successful scale-up of laboratory results in transesterification requires so much information obtained through chemical kinetics.This paper presents the kinetics and thermodynamic study of alkali-homogeneous irreversible methanolysis of seed oil derived from African pear. The transesterification process was carried out from 0-100 minutes at temperature range of 55-65°C. The reaction mixture compositions were ascertained using gas chromatography- flame ionization detector (GC-FID) technique. Rate constants of the triglyceride (Tg), diglycerides (Dg) and monoglycerides(Mg) hydrolysis were in the range of 0.0140- 0.07810 wt%/min and increased with increase in temperature. The rate of reaction was found to increase with increase in temperature. Activation energies were found to be 6.14, 20.01 and 28.5kcal/mol at 55, 60 and 65oC respectively. Tg hydrolysis to Dg was observed asthe rate determining step while the reaction agreed with second order principles. A biodiesel yield of 93.02% was obtained with cloud point of 10°C , flash point of 125°C , pour point of 4°C , calorific value of 34.4MJ/kg,  and cetane number of 54.90 which satisfy EN14214 and ASTM D 6751 standards. Results presented in this report would serve as idealized conditions for industrial scale up of biodiesel production from African pear seed oil.

 

Author Biographies

C. Esonye

Department of Chemical/ Engineering, Alex Ekwueme Federal University, Ndufu-Alike Ikwo, Abakaliki, Nigeria; 

 

O.D. Onukwuli

Department of Chemical Engineering, NnamdiAzikiwe University, Awka, Nigeria; 

 

S.O. Momoh

Research and Development Unit, National Agency for Science and Engineering Infrastructure, Abuja, Nigeria.

Published
2021-08-25