Optimization of bio-oil pH with co-pyrolysis of cotton gin trash, animal manure, and micro-algae

摘要

Lower pH increases corrosive nature of bio-oil and hence creates problem in its applications for a replacement of crude oil. We controlled pH of bio-oil by optimizing the temperature and feedstock composition in a fixed bed batch pyrolysis reactor. The feedstock used for pyrolysis of co-biomass included cotton gin trash (CGT), cow manure (CM), and algae (Nanochloropsis oculata). The bio-oil from co-pyrolysis process was also characterized for water content viscosity, pH, and acid number. The co-biomass in different ratios was processed to produce bio-oil at five operating temperatures (400, 450, 500, 550, and 600°C). The results obtained during the experiment showed a significant change in the product yields and characteristics. The pH of produced bio-oil ranged from 6.36 to 8.96. The ratios of feedstock compositions showed synergistic effect on the pH, acid number, and viscosity of bio-oil. The results indicated that operating temperature and composition of co-biomass are critical in improving the pH of the bio-oil.