Aromatic amination of refined rice bran oil previously epoxidized with Novozym 435

Resumen

Objective: To aromatically aminate refined rice bran oil (RBO), a by-product of the rice agro-industry,through a chemical-enzymatic epoxidation based on Novozym 435 and p-xylylenediamine insertion.
Design/Methodology/Approach: Refined RBO was epoxidized with H2O2/Novozym 435. The resulting
epoxidized rice bran oil (eRBO) was functionalized with the p-xylylenediamine aromatic diamine via epoxy
ring-opening (X-eRBO), using ZnCl2 as catalyst. Iodine value (IV), saponification value (SV), and oxirane
oxygen content (OOC) were determined to evaluate structural changes in oils. The RBO, the eRBO, and the
X-eRBO were identified using FTIR, 1H, and 13C NMR.
Results: The IV, the SV, and the OOC suggest that the synthesis of eRBO and X-eRBO were effective. The
increase of molecular weight in eRBO point to the formation of 6 epoxy rings per original triglyceride. The
OOC value of X-eRBO was 22% lower than the OOC value of eRBO, implying that an effective aromatic
amination was achieved. The FTIR, 1H and 13C NMR spectroscopy analysis confirmed the epoxidation and
amination of the RBO.
Study Limitations/Implications: X-eRBO may be a feasible precursor for value-added products, such as
crosslinked polymers or corrosion inhibitors.
Findings/Conclusions: Refined rice bran oil was aromatically aminated after two stages under mild thermal conditions. This result was achieved with an epoxidation sequence with H2O2/Novozym 435, followed by
functionalization with p-xylylenediamine.