Ozone detoxification of steam-pretreated Norway spruce

Table 2 Comparison of detoxification methods for improved fermentability of spruce pretreatment liquid

	Fermentable hexoses (glucose and mannose) at start (g/L)	Fermentable hexoses (glucose and mannose) after 24 h (g/L)	Consumed sugar (glucose and mannose) (g/L)	Ethanol yield^a	Balanced ethanol yield^b	Ethanol productivity^c
Reference	20.3	<0.01	20.3	0.51	0.51	0.43
Untreated	20.6	16.5	4.1	0.43	0.09	0.07
Alkali	19.0	<0.01	19.0	0.50	0.50	0.40
Dithionite	21.0	<0.01	21.0	0.49	0.49	0.43
Ozone 0.75 g	20.3	8.4	11.9	0.45	0.26	0.22
Fenton’s reagent	20.8	17.0	3.8	0.37	0.07	0.06

The table compares the concentrations of fermentable hexose sugars at the start of the experiment and after 24 h of fermentation after detoxification using different methods. The relative standard deviation of the method that was used for monosaccharide and ethanol analysis was estimated to <10 %
^ag EtOH/g consumed glucose and mannose
^bg EtOH/g glucose and mannose prior to fermentation
^cg EtOH × L⁻¹ × h⁻¹

ISSN: 2731-3654