Continuous Synthesis of Biodiesel from Outstanding Kernel Oil in a Packed Bed Reactor Using Burkholderia cepacia Lipase Immobilized on Magnetic Nanosupport

• Published in: Catalysis letters Vol. 152; no. 8; pp. 2434 - 2444
• Main Authors: Bento, Heitor B. S., Reis, Cristiano E. R., Pinto, Pedro A., Cortez, Daniela V., Vilas Bôas, Renata N., Costa-Silva, Tales A., Carvalho, Ana K. F., de Castro, Heizir F.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-08-2022; Springer; Springer Nature B.V
• Subjects: Biodiesel fuels; Catalysis; Chemistry; Chemistry and Materials Science; Continuous flow; Enzyme activity; Enzymes; Esterification; Esters; Ethanol; Ethyl esters; Fixed bed reactors; Fixed beds; Immobilization; Industrial Chemistry/Chemical Engineering; Iron oxides; Kernels; Lipase; Organometallic Chemistry; Packed beds; Physical Chemistry; Productivity; Synthesis; Thermal stability; Transesterification; Enzyme immobilization; Continuous reaction; Lipase; Biodiesel; Magnetic nanoparticles
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-021-03826-y

This study deals with the use of commercial lipase stabilized onto magnetic particles of iron oxides (Fe
3
O
4
/γ-Fe
2
O
3
) and applied as a heterogeneous biocatalyst in the synthesis of ethyl esters (biodiesel) in a solvent-free medium on a continuous process. Magnetic particles were synthesized by alkaline co-precipitation, silanized, activated and subsequently used for immobilization of
Burkholderia cepacia
lipase. The results regarding the lipase immobilization showed an enzyme activity retention of about 53% and an increase in the K
M
value in about threefold (from 410 to 1262 mmol L
−1
) and a decrease in the V
max
value in sevenfold (From 12,390 to 1786 U g
−1
) when compared with the free enzyme. The immobilization process favored the thermal stability and increased the half-time of the enzyme about tenfold at 50 °C. The immobilized derivative was evaluated to aroma production and the activity of esterification was calculated as being 56.7 μmol L
−1
 g
−1
 min
−1
, which corresponds to a productivity value of 0.58 g ester L
−1
 h
−1
. The immobilized system was also used to mediate transesterification of kernel oil in a fixed bed reactor operating in a continuous flow with a reaction medium composed of oil and ethanol at a molar ratio of 1:12, 50 °C and space–time of 16 h. The operational stability of the immobilized lipase estimated at 47 days allowed to operate the reactor with high productivity of 38.7 ± 0.7 mg g
−1
 h
−1
. Also, the product properties of the ester content (> 96.5%) and kinematic viscosity value (5.32 ± 0.4 mm
2
s
−1
at 40 °C) meet the requirements of the ANP and ASTM (D6751) for biodiesel fuel.
Graphic Abstract