Thermogravimetric analysis is commonly used to determine the kinetic constants of biomass pyrolysis. Fig. 3 shows the TG and DTG curves for monoculture and co-culture treated corn stover.There were three distinct stages of weight loss: the first stage of dehydration ranged from 25 to 150 ◦C, the second stage of active pyrolysis ranged from 150 to 400 ◦C, and the third stage of residual or passive pyrolysis ranged from 400 to 1000 ◦C. Due to hemicellulose degradation, there was a shoulder peak for the biopretreated sample in the second stage. The initial pyrolysis temperature of the biopretreated sample (214 ◦C for co-culture and I. lacteus CD2, 222 ◦Cfor A. polytricha AP)waslower than that of the control sample
(232 ◦C), and the thermal degradation of the biopretreated sample was accelerated in early pyrolysis (from 150 to 275 ◦C). In the passive stage, the thermal degradation ratio of the control sample was higher than that of biopretreated samples, and the thermal degradation ratio of A. polytricha AP was higher than that of I. lacteus CD2 and the co-culture. There was no significant difference in the temperature of the maximum devolatilization rate (318 ◦C for twomonocultures, 321 ◦C for the control and co-culture). The final temperature of biotreated samples was higher than that of the control sample. The reaction interval (the temperature interval from initial temperature to final temperature) broadened because of the lignin
enrichment by biological treatment. The maximal weight loss rate of the I. lacteus CD2 treated sample was lower than that of A. polytricha AP and the co-culture. The maximal weight loss rate was: I. lacteus CD2 < co-culture < A. polytricha AP < control. The char content of the co-culture treating sample with highest amount of lignin was highest and the char content of the control sample with lowest amount of lignin was lowest. The char content was in linear relation with the lignin content (Table 2).