write 2-3 pages regarding the global issues of butanol production from ABE fermentation, the ABE (Acetone, Butanol, and Ethanol) fermentation process using Clostridia bacteria used to be common.
here are some sources that can help you and you can find other source if these sources did not help.
https://www.e-education.psu.edu/egee439/node/648
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4980751/
https://www.sciencedirect.com/science/article/pii/S2215017X15000430
https://etd.ohiolink.edu/rws_etd/document/get/ysu1242762960/inline
http://cdn.intechopen.com/pdfs/43682/InTech-The_promising_fuel_biobutanol.pdf
https://pubs.acs.org/doi/full/10.1021/acs.energyfuels.6b00819?src=recsys