Production optimization, scale-up, and characterization of biodiesel from marine fishmeal plant oil using Portunus sanguinolentus crab shell derived heterogeneous catalyst

The current article primarily focuses on utilizing Portunus sanguinolentus crab shells to prepare a
heterogeneous base catalyst for the transesterification of marine fishmeal plant (MFMP) oil. A
heterogeneous catalyst (powder) was prepared by calcination of crab shell at 900 °C for 4 h. X-
ray diffraction, Fourier transform infrared spectroscopy, Scanning electron microscopy, and
Brunauer-Emmett-Teller analysis unveiled that crab shell-derived catalyst powder was crystalline
mesoporous and predominantly comprising of CaO with a total surface area of 3.654 (m2/g). The
central composite design of response surface methodology performed at varying levels of four
factors such as oil to methanol molar ratio (7.5–10.5 mol/mol), calcined crab shell catalyst con-
centration (2–4 wt% of oil), reaction temperature (55–65 °C) and reaction time (45–75 min) was
chosen for optimization. Maximum biodiesel yield of 88.56 wt% was obtained at 1:9 (mol/mol)
oil to methanol molar ratio, 3 wt% calcined crab shell catalyst concentration, 60 °C reaction tem-
perature, and 60 min reaction time. Further, biodiesel production was scaled to a 50 L oil volume
batch using the optimized condition at flask level and achieved a yield of 87.47 wt%. The physic-
ochemical characteristics of biodiesel from the optimization study and scale-up study endorsed
that the biodiesel quality was feasible. Moreover, the catalyst reusability study showed good
reusability potential up to 4 cycles with 10% catalytic activity loss, thereby ensuring its signifi-
cance for sustainable biodiesel production. Therefore, the MFMP oil and calcined crab shell cata-
lyst could be employed as a new alternative feedstock and catalyst source for sustainable
biodiesel production.