. 2023 Jun 21;13(13):1901. doi: 10.3390/nano13131901

Table 3.

Analysis of liquid products obtained from the glycerolysis of urea over various mixed oxide catalysts prepared at different calcined temperatures. (Reaction temperature = 140 °C, reaction time = 5 h, reaction pressure = 3 kPa, glycerol/urea ratio = 1:1). (2): 2,3-dihydroxypropyl carbamate, (4): 4 (hydroxymethyl)oxazolidin-2-one, and (5): (2-oxo-1,3-dioxolan-4-yl) methylcarbamate.

Catalyst	Glycerol Conversion (%)	GC Yield (%)	Selectivity (%)				Acidic Sites (mmol/g)	Basic Sites (mmol/g)
Catalyst	Glycerol Conversion (%)	GC Yield (%)	GC	(2)	(4)	(5)	Acidic Sites (mmol/g)	Basic Sites (mmol/g)
ZnAl₂O₄-550	72.2 ± 0.7	33 ± 0.3	45.8 ± 0.5	34.3 ± 0.1	12.4 ± 0.2	7.5 ± 0.1	0.45	0.23
ZnAl₂O₄-650	72.2 ± 0.8	30 ± 0.3	40.9 ± 0.7	40.9 ± 0.3	10.9 ± 0.2	7.3 ± 0.1	0.32	0.13