Table 1. Levulinic acid Yield (%) depending on substrate concentration, solvent, catalyst, temperature and reaction time

Substrate conc.	Solvent	Catalyst	Catalyst conc.	Temp. (°C)	Reaction/residence time	Levulinic acid Yield (wt%)	Reference
Glucose (1:100)	Ethanol (50% v/v)	H2SO4	1%	220		22.5	This work
Glucose (2 w.t%)	Water	H2SO4	0.5M	180	15 min	42	Rackemann et al. (2014)
Glucose (5 w.t%)	Water	H2SO4	5%	170	1 h	80.7	Chun et al. (2006)
Glucose (2 w.t%)	Water	H2SO4	1M	140	2 h	38	Girisuta et al. (2006)