title: Pretreatment of Corn Stover by Low Moisture Anhydrous Ammonia (LMAA) in a Pilot-Scale Reactor and Bioconversion to Fuel Ethanol and Industrial Chemicals.
abstract: Corn stover (CS) adjusted to 50, 66, and 70 % moisture was pretreated by the low moisture anhydrous ammonia (LMAA) process in a pilot-scale ammoniation reactor. After ammoniation, the 70 % moisture CS was treated at 90 and 100 °C whereas the others were treated at 90 °C only. The 70 % moisture pretreated CS then was subjected to a storage study under non-sterile conditions for 3 months. It was found that storage time did not have significant effects on the compositions of the pretreated materials and their hydrolysis by commercial enzymes. The 70 % moisture CS treated at 90 °C was used for preparation of a mix sugar hydrolysate (MSH) using combination of cellulase and xylanase. The MSH was used to prepare a corn mash at 9.5 wt% solid then subjected to ethanol fermentation by Escherichia coli KO11. The 66 % moisture CS treated at 90 °C was hydrolyzed with xylanase to make a xylose-rich hydrolysate (XRH), which was subsequently used for butyric acid fermentation by Clostridium tyrobutyricum. The resultant cellulose-enriched residue was hydrolyzed with cellulase to make a glucose-rich hydrolysate (GRH), which was subsequently used for succinic acid fermentation by E. coli AFP184.
authors.affiliation: Sustainable Biofuels and Co-products Research Unit, Eastern Regional Research Center, Agricultural Research Service, USDA, Wyndmoor, PA, 19038, USA. john.nghiem@ars.usda.gov.
authors.forename: Nhuan P
authors.initials: NP
authors.lastname: Nghiem
authors.affiliation: Sustainable Biofuels and Co-products Research Unit, Eastern Regional Research Center, Agricultural Research Service, USDA, Wyndmoor, PA, 19038, USA.
authors.forename: Gerard E
authors.initials: GE
authors.lastname: Senske
authors.affiliation: Department of Environmental Engineering, Kongju National University, Cheonandae-Ro, 1223-24, Cheonan, Chungnam, 31080, Korea.
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Kim
mesh_terms: D000641:Ammonia / Q000737:chemistry / Q000494:pharmacology; D019149:Bioreactors; D002480:Cellulase / Q000737:chemistry*; D002482:Cellulose / Q000096:biosynthesis / Q000737:chemistry; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics; D000431:Ethanol / Q000138:chemical synthesis / Q000737:chemistry*; D005285:Fermentation; D006868:Hydrolysis; D008031:Lignin / Q000096:biosynthesis / Q000737:chemistry; D019802:Succinic Acid / Q000737:chemistry; D014994:Xylose / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry / Q000187:drug effects
chemical_list: D000431:Ethanol; D000641:Ammonia; D002482:Cellulose; D008031:Lignin; D014994:Xylose; D019802:Succinic Acid; D002480:Cellulase; D043364:Endo-1,4-beta Xylanases
keywords: Cellulosic biomass; Corn stover; Ethanol; Fermentation; Low moisture anhydrous ammonia; Pretreatment; Value-added products