Electronic Supplementary Material (ESI) for Energy & Environmental Science. This journal is The Royal Society of Chemistry 2016 Supplementary Materials for CO 2 enabled process integration for the production of cellulosic ethanol using bionic liquids Jian Sun a,b, NVSN M. Konda a,c, Jian Shi a,b, Ramakrishnan Parthasarathi a,b, Tanmoy Dutta a,b, Feng Xu a,b, Corinne Scown a,d, Blake A. Simmons a,b, Seema Singh a,b* a Deconstruction Division, Joint BioEnergy Institute, Emeryville, CA, USA b Biological and Engineering Sciences Center, Sandia National Laboratories, Livermore, CA, USA c Biological Systems Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. d Energy Analysis and Environmental Impacts Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. *Corresponding author. E-mail: seesing@sandia.gov. This PDF file includes: Figures S1-12 Tables S1-3 1
a OD 600 Growth time (h) b OD 600 Growth time (h) Figure S1. Toxicity screening of fifteen ILs on Saccharomyces cerevisiae strain BY4741 at (A) 0.6 wt% and (B) 5 wt% IL. 2
Relative activity on MCC (%) 100 80 60 40 20 [Ch][Lys] [C2C1Im][OAc] 0 0 5 10 20 Concentration of IL/wt% 30 40 Figure S2. Inhibition of IL concentration to the hydrolysis of microcrystalline cellulose (MCC) by commercial enzyme cocktails. Conditions: pretreatment, MCC 50 mg, liquid 1.5 ml, 140 C, 1h; saccharification, 30 mg CTec2+HTec2 protein/g Avicel, 50 mm citric buffer, ph 5, 50 C, 72 h. 3
1 N + O - 1 O NH 2 OH NH 2 1 2 3 4 Figure S3. 13 C NMR (150 MHz, DMSO-d6, 298K) spectra of [Ch][Lys] before (top) and after CO 2 absorption (bottom). 13 C NMR spectra of [Ch][Lys] shows one signal for carbonyl carbon (1, top spectra). Upon CO 2 absorption the 13 C NMR spectra of [Ch][Lys] shows four signals for carbonyl carbon (1-4, bottom spectra), which are indicative of different IL-H 2 O- CO 2 complexes. 4
Relative activity on MCC (%) 80 70 60 50 40 30 20 10 0 HCl AcOH H 3 PO 4 Citric acid Lactic acid HCOOH H 2 SO 4 Control Acids used for ph adjustment Figure S4. Effect of acid-induced ph adjustments on enzymatic hydrolysis of MCC. Conditions: MCC (50 mg), liquid 1.5 ml, [Ch][Lys] (5 wt%), 30 mg CTec2+HTec2 protein /g Avicel, 50 mm citric buffer, ph 5.0, 50 C, 72 h. 5
80 Sugar yield (%) 70 60 50 40 Glucose Xylose 30 20 10 0 5 10 20 IL concentration (wt%) Figure S5. Comparison of sugar yields using different concentration of [Ch][Lys] for both pretreatment and saccharification process. Conditions: pretreatment, 10 wt% switchgrass loading, 5 (10 or 20) wt% [Ch][Lys], 85 (80 or 70) wt% H 2 O, 140 C, 1h; Saccharification, 10 mg CTec2+HTec2 protein /g SG, 50 C, 72 h and 1 MPa CO 2. 6
Switchgrass (SG) 1.0 kg weight 0.296 kg glucan 0.184 kg xylan 0.200 kg lignin 0.320 kg others 140, 3h 10% solid loading Ionic Liquid Pretreatment [Ch][Lys] 1.0 kg Water 8.0 kg CTec+HTec, 10 g 10 g/kg SG Yeast, 0.1 kg 0.1 kg/kg SG (5 g/l) Simultaneous Saccharifica on and Fermenta on (SFF) IL recycle Water 10.0 kg Liquid 5.0 g glucose 0.095 kg xylose 0.079 kg xylose oligomers 1.0 kg [Ch][Lys] 0.031 kg lignin 0.139 kg ethanol Ethanol production: 0.139 g ethanol/g switchgrass; Ethanol yield: 83.3%. 0. 286 kg dry residual solid Solids 0.026 kg glucan 0.011 kg xylan 0.169 kg lignin 0.08 kg others Figure S6. Overall mass balance of the integrated process using [Ch][Lys], carbon dioxide, commercial enzyme cocktail and wild type yeast S. cerevisiae. 7
Water CTec2/HTec2 Water Yeast Biomass [C 2 C 1 Im[OAc] Pretreatment Water-wash Saccharification Fermentation IL recycle Pervaporation Ultrafiltration Distillation Stillage (to boiler & WWT) Water (to WWT) Solids (to boiler) Ethanol Figure S7. Simplified block flow diagram of water-wash process configuration. 8
JTherm Water NaOH / HCl Yeast Biomass [C 2 C 1 Im[OAc] Pretreatment Saccharification S/L LLE Sugars Fermentation IL recycle Solids (to boiler) Pervaporation Ultrafiltration Distillation Stillage (to boiler & WWT) Water (to WWT) Ethanol Figure S8. Simplified block flow diagram of JTherm process configuration with liquid-liquid extraction (LLE) to recover sugars from hydrolysate. 9
CTec2/HTec2 CO 2 Yeast CO 2 Biomass Aq. [Ch][Lys] Pretreatment Pre- Sccharification SSF S/L separation (Centrifugation) Solids (to boiler) Ultrafiltration Solids (to boiler) IL recycle Pervaporation Water (to WWT) Distillation Ethanol Figure S9. Simplified block flow diagram of integrated CO 2 process configuration. 10
Glucose titer (g/l) 70 60 50 40 30 20 Enzyme loading: 10 mg/g SG Enzyme loading: 20 mg/g SG 10 0 10 Biomass loading (wt%) 15 20 30 Figure S10. Effect of biomass and enzyme loading on glucose titer. 11
MESP ($/gal) 15 10 5 MESP 368 AOC 520 184 600 400 200 Annual Operating Cost (AOC, M$/year) 0 WW Jtherm Integrated CO2 Three different routes studied in TEA 0 Figure S11. Minimum selling price (MESP) and annual operating cost (AOC) for the WW, JTherm, and integrated CO 2 schemes. 12
Figure S12. Detailed section-wide cost breakdown for the WW, JTherm, and integrated CO 2 routes. 13
Table S1. Calculated acidity of [Ch][Lys] with CO 2 and water molecules and local chemical reactivity descriptors of terminal and side chain N atoms. Calculated Acidity (ev) Terminal Side [Ch][Lys] (H 2 O) 2 2.3 0.142 0.039 [Ch][Lys] (H 2 O) (CO 2 ) (side) 2.36 0.291 0.007 [Ch][Lys] (H 2 O) (CO 2 ) (ter.) 2.7 0.015 0.065 [Ch][Lys] (H 2 O) 2 (CO 2 ) 2 2.7 0.017 0.026 f k - 14
Table S2. Chemical composition of dominant components in the switchgrass studied and solid recovery. Solid recovery/% Glucan /wt% Xylan/wt% Lignin/wt% Untreated SG / 32.2±0.1 20.0±0.1 21.8±0.2 10% IL, 1h 65.8 44.7±0.7 24.0±1.2 9.2±0.2 10% IL, 3h 63.2 47.8±0.7 23.6±1.0 9.2±0.3 90% IL, 1h 45.7 62.3±0.7 24.0±0.3 6.5±0.1 Pretreatment conditions: 10% biomass loading, [Ch][Lys], H 2 O (0 or 80%), 140. Table S3. Key process and economic data for the three scenarios studied in the TEA Process configuration WW a JTherm b Integrated CO 2 15
Biomass processed (dry MT/day) 2000 2000 2000 Biomass price ($/dry ton, delivered at plantgate) 80 80 80 Pretreatment IL used [C 2 C 1 Im][OAc] [C 2 C 1 Im][OAc [Ch][Lys] ] IL price ($/kg) c 10 10 2 IL purity (wt% of IL in aqueous IL solution 90 100 13.5 [IL:H 2 O]) Biomass loading (wt%) 20 20 20 IL recovery (%) 99.9 99.9 99.9 Water loading (mass ratio between fresh water 20 N/A N/A and biomass in water-wash step in WW route) Loss of glucan in water-wash step (wt% of 5 NONE NONE initial glucan) Loss of xylan in water-wash step (wt% of initial 24 NONE NONE xylan) Hydrolysis Configuration SHF SHF SSF Enzyme type CTec2/HTec2 JTherm CTec2/Htec2 Enzyme price ($/kg protein) d 4.29 10 4.29 Enzyme loading (mg/g glucan) 20 20 20 Operating pressure (atm) 1 1 20 (~2 MPa) Operating temperature (C) 50 70 50 Operating time (hr) 72 72 24 (pre-hydrolysis) Glucan-to-glucose conversion (%) 90 90 90 Xylan-to-xylose conversion (%) 90 90 90 Sugar losses during extraction (%) N/A 5 N/A Fermentation Co-fermentation of glucose and xylose YES YES YES Glucose-to-ethanol conversion (%) 90 90 90 Xylose-to-ethanol conversion (%) 90 90 90 Xylose-to-ethanol conversion (%) 90 90 90 Operating pressure (atm) 1 1 20 (~2 MPa) Opiating temperature (C) 32 32 32 Operating time (hr) 72 72 72 a based on (Bai, Wang et al. 2013, Cruz, Scullin et al. 2013, Konda, Shi et al. 2014, Shi, Balamurugan et al. 2014, Li, Tanjore et al. 2015) b (Konda, Shi et al. 2014, Shi, Balamurugan et al. 2014) c price of ILs is assumed to reflect on the fact that the choline based ILs use cheaper raw materials and require simpler synthesis methods. For instance, according to the information available in the open literature (e.g., www.alibaba.com), both choline hydroxide and lysine (i.e., the primary raw materials used to synthesize [Ch][Lys]) can be purchased for about $700-$1500/MT (depending on the supplier, quality and order quanity). Moreover, the synthesis of [Ch][Lys] is fairly simple and doesn t require extensive concentration/purification steps as the OP-CO 2 process uses aqueous IL. Therefore, a price of $2/kg of [Ch][Lys] is a reasonable estimate in this preliminary TEA. Furthermore, a sensitivity analysis around IL price (varying from $1 to $10/kg) is conducted. d price of enzyme is assumed to reflect that the novel enzymes (JTtherm) are likely to be more expensive compared to the commercial enzymes (CTec2/HTec2) 16