1. 1 NREL Update—CAFI 2 Teleconference Rick Elander National Renewable Energy Laboratory National Bioenergy Center Golden, CO February 18, 2004 Biomass Refining CAFI

2. 2 Outline Dilute Acid Pretreated Corn Stover Data Dilute Acid Pretreated Hybrid Poplar Data (Bench Scale-Steam Gun) Description of Dilute Acid Pretreated Hybrid Poplar (Pilot Scale-Sunds Reactor) –Data not yet available Biomass Refining CAFI

3. 3 Dilute Acid Pretreated Corn Stover Feedstock: 2 nd pass corn stover from Kramer farm (Wray, CO) –Collected using high rake setting to avoid soil pick-up –Milled to pass 0.25 inch screen (Mitts and Merril knife mill) –Pretreated in Sunds vertical reactor, with and without hot washing Biomass Refining CAFI

4. 4 Pilot Scale Sunds Vertical Reactor Steam, Hot Water, Hot Acid, Alkali, or Solvent, Hot Air Pneumapress Filter Pressurized Solids Tank (Jaygo Reactor) Steam, Hot Water, Hot Acid or Alkali High Solids Discflo Pump and Heated Transfer Line Optional “Hot-Washing” in Pneumapress Filter

5. 5 Dilute Acid Pretreated Corn Stover Pretreatment Conditions: 1.Typical “mid severity” condition in the Sunds vertical pretreatment reactor (190 C, ~ 1.5 minute residence time in “flowthrough mode”, 0.045 g sulfuric acid/g dry feedstock, 30% insoluble solids) 2.“Low severity” condition in the Sunds vertical pretreatment reactor (180 C, ~ 1.5 minute residence time in “flowthrough mode”, 0.03 g sulfuric acid/g dry feedstock, 25% insoluble solids) 3.“Low severity” condition in the Sunds vertical pretreatment reactor (180 C, ~ 1.5 minute residence time in “flowthrough mode”, 0.03 g sulfuric acid/g dry feedstock, 25% insoluble solids) and hot washed in Pneumapress pressure belt filter with hot water. Biomass Refining CAFI

6. 6 Dilute Acid Pretreated Corn Stover— Pretreated Solids Composition and Component Solubilization Biomass Refining CAFI

7. 7 Dilute Acid Pretreated Hybrid Poplar (Bench Scale-Steam Gun) Feedstock: USDA-supplied hybrid poplar (Alexandria, MN) –Debarked, chipped, and milled to pass 0.25 inch screen (Mitts and Merril knife mill) –Pre-impregnated with H 2 SO 4 and pretreated in 4 L NREL steam gun Biomass Refining CAFI

8. 8 Dilute Acid Pretreated Poplar in Steam Gun Biomass Refining CAFI 190 C 70 s Acid Loading: 0.02 g H 2 SO 4 /g bone dry feedstock 190 C 120 s 200 C 70 s 200 C 120 s

9. 9 Composition of Pretreated Solids from Dilute Acid Pretreated Hybrid Poplar (Bench Scale-Steam Gun) Biomass Refining CAFI

10. 10 Composition of Pretreated Liquids from Dilute Acid Pretreated Hybrid Poplar (Bench Scale-Steam Gun) Biomass Refining CAFI

11. 11 Glucose and Xylose Component Balance from Dilute Acid Pretreated Hybrid Poplar (Bench Scale-Steam Gun) Biomass Refining CAFI

12. 12 Example of Detailed Component Balance from Dilute Acid Pretreated Hybrid Poplar (Bench Scale-Steam Gun) Biomass Refining CAFI

13. 13 Dilute Acid Pretreated Hybrid Poplar (Pilot Scale-Sunds Reactor) Feedstock: USDA-supplied hybrid poplar (Alexandria, MN) –Debarked, chipped, and milled to pass 0.25 inch screen (Mitts and Merril knife mill) Utilized Sunds reactor, with and without Pneumapress hot washing Pretreatment conducted at less severe conditions than steam gun runs, due to apparent “over-pretreatment” –175 C, ~ 1.5 minute residence time in “flowthrough mode”, 0.025 g sulfuric acid/g dry feedstock, 25% insoluble solids Five samples sent –Separation only (no washing) –Hot water washed –Hot dilute ethanol (0.5 wt%) washed –Hot dilute NaOH (0.2 wt%) washed –Hot dilute ethanol (0.5 wt%) and NaOH (0.2 wt%) washed Compositional analysis and mass balance data not yet available Biomass Refining CAFI

14. 14 CAFI Labeling Nomenclature for Previously Sent Samples Biomass Refining CAFI