Novel sustainable biodiesel production from low-grade oleic acid via esterification catalyzed by characterized crystalline ZrO2/Al2O3

Table 1 Comparison of ZrO₂/Al₂O₃ with other solid acid catalysts

Catalysts	Temperature (C^o)	A/O Molar ratio	Catalysts loading (wt %)	Oil Conversion (%)	Reusability	Ref.
ZrO₂/Al₂O₃	70	10:1	4	90.5	4 cycles	This work
SO₄^{− 2} /ZnO	65	6:1	4	80.2		[45]
ZrO₂ –Supp. AC zeolite	65	10:1	10	84.2		[46]
SO₄^{− 2} / ZrO₂- Al₂O₃	180	8:1	6	83.8		[47]
AC from Corncob	75	6:1	20	88.7		[48]

ISSN: 2661-801X