Progress 12/01/14 to 11/30/15

Outputs
Target Audience:The target audience is potential biofuels producers in areas of the ardi west. We also are seeking to inform the general public on the value of arid lands for production of biofuels and bioproducts. Changes/Problems: The research is going as expected with the original goals. However, after two years of research, we will emphasize the grindelia work and perhaps de-emphasize the efforts on obtianing rubber from rabbitbrush, although this next year, we are planning on additional effort on germinating and growing rabbibrush under agronomic conditions. Germination of wild plants under agronomic conditions is an unexpected challenge, and we will be examining this aspect with additional effort than originally expected. What opportunities for training and professional development has the project provided? Three graduate students and two undergraduates are beingtrainedon this project. One is in the Chemical Engineering group, and two are in the Natural Resources and Environmental Science group. One student, Bishnu Neupane, will complete his Ph.D. on gumweed growth and extraction in 2016. The undergraduates were utilized both for the field studies and the laboratory studies. In addition, we have high school students working as volunteers on the project, who help primarily in the field work. ? Plans of next annum: Optimization of solvothermolysis using supercritical methanol with CO2 as co-solvent. Qualitative and quantitative determination of chemical species of the biocrude Prepare a manuscript for Journal of Supercritical Fluids (impact factor: 2.37). Literature has been studied for successful extraction by using supercritical methanol with ScCO2 as co-solvent. The process is called solvothermolysis. Supercritical methanol is an effective reaction medium for producing biocrude from lignocellulosic biomass with high yield (~30wt.%) at 300 °C [1]. Using sodium carbonate both as catalyst and CO2 source was also reported for production of heavy oils in one-pot synthesis from woody biomass [2]. Preliminary experiments have been performed using whole gumweed as feedstock at various solvothermolysis temperatures (240, 245, 250 °C) with or without 10 vol.% ScCO2. Our preliminary study shows biocrude yield up to 40wt.% from whole gumweed at 250 °C in only 30 min. The resulted biocrude was chemically analyzed with GCMS, and FTIR as well as the energy value and density were measured. Plans of next annum: Optimization of solvothermolysis using supercritical methanol with CO2 as co-solvent. Qualitative and quantitative determination of chemical species of the biocrude Prepare a manuscript for Journal of Supercritical Fluids (impact factor: 2.37). How have the results been disseminated to communities of interest? This work has been presented in two presentations at scientific meetings, and is available in one peer-reviewed article. A much more extensive dissemination of this research was initiated by an article written by Scott Sonner of the Associated Press. He is a regional reporterwho interviewed project participants in late 2015, and produced an article that was printed locally on the project. It was picked up by the San Francisco Chronicle and the New York Times, as well as the Albuquerque newspaper and other regional newspapers. It was additionally published (following additional interview of project participants) in the Biofuels Journal. What do you plan to do during the next reporting period to accomplish the goals? To fulfill the project goals, the accurate analysis oxygen content in the oil phase, aqueous phase, gas phase, and solid phase products from the gumweed biocrude in the new BiTCP system is necessary. Reaction conditions will be optimized to maximize the yields of desired jet-fuel range hydrocarbons with cyclic rings. In addition, reaction mechanism in BiTCP will be explored. Moreover, the physical properties of liquid hydrocarbon fuel products will be tested. We plan to optimize thesolvothermolysis using supercritical methanol with CO2 as co-solvent. We will also conduct qualitative and quantitative determination of chemical species of the biocrude. Finally, we will prepare a manuscript for the Journal of Supercritical Fluids (impact factor: 2.37). A larger planting of gumweed will be initiated this year to examine the irrigation needs of the plant, and also examine the salt tolerance of the plant. We will continue to examine the conversion of biocrude via pyrolysis to a usable fuel. Additional effort will be expended on appropriate methods for germination of gumweed under field conditions. We will submit in mid-2016 a manuscript to a peer review publicaiton on the agronomic aspects of growing grindelia.

Impacts
What was accomplished under these goals? 1. Develop green extraction and processing methods for both rabbitbrush and gumweed and characterize the remaining begass as to their potential for use as pelletized fuels. Literature has been studied for successful extraction by using supercritical methanol with ScCO2 as co-solvent. The process is called solvothermolysis. Supercritical methanol is an effective reaction medium for producing biocrude from lignocellulosic biomass with high yield (~30wt.%) at 300 °C [1]. Using sodium carbonate both as catalyst and CO2 source was also reported for production of heavy oils in one-pot synthesis from woody biomass [2] Preliminary experiments have been performed using whole gumweed as feedstock at various solvothermolysis temperatures (240, 245, 250 °C) with or without 10 vol.% ScCO2. Our preliminary study shows biocrude yield up to 40wt.% from whole gumweed at 250 °C in only 30 min. The resulted biocrude was chemically analyzed with GCMS, and FTIR as well as the energy value and density were measured. 2.Elucidate the catalytic reaction mechanisms and pathways of converting gumweed biocrude into hydrocarbon fuels using aqueous phase hydrotreating (APH): A bi-functional catalyst, tungstate zirconia supported palladium (Pd/W-ZrO2), was designed for the catalytic conversion of gumweed biocrude in the aqueous phase solutions. The product distribution was influenced significantly by process conditions. High reaction temperature, long reaction time and high H2 pressure are needed for de-oxygenation of grindelic acid. We found that the optimum reaction conditions to convert 1 g of gumweed biocrude were at 240oC and 400 psi H2 with 0.5g 1% Pd/W-ZrO2 catalyst. After reacting for 1 hour, the oxygen content in the oil products deceased to 5.9 % from 19.0 % in the gumweed biocrude feedstock. Approximately 80 wt % oil phase was produced among which ~ 45 % was in the jet fuel range. The carbon distribution in the products of gumweed biocrude conversion was analyzed by GC-MS, ESI-MS, GC-TCD and elemental analyzer. We found that more than 90 % carbon was distributed in the oil phase while less than 8 % carbon was in aqueous phase, ~ 1 % in gas phase and another 1 % in solid phase at the optimum reaction conditions. It was found that C1 to C5 carboxylic acids, including formic acid, acetic acid, lactic acid, levulinic acid and 2-methyl succinic acid, were the main compounds in aqueous phase. In gas phase, CO2 and the trace amount of CO and CH4 were detected. Elemental analyzer was used to analyze the solid phase products and we found that less than 1carbon was in solid state. By increasing the reaction temperature, the conversion of the grindelic acid increased but the oxygen content in oil phase products decreased. However, an appreciable amount of by-products in aqueous, gas and solid phase were also formed and the carbon yield of desired oil phase products decreased. The oxygen content in the oil phase products almost had no change after increasing temperature higher than 240oC. However, the opening of cyclic ether ring in the grindelic acid molecule is still a challenge in the aqueous phase hydrodeoxygenation reactions. In order to achieve complete oxygen removal from the gumweed biocrude, we proposed a new conversion strategy, bi-phasic tandem catalytic process (BiTCP). The model terpenoid compound, 1,8-cineole, was used as the feedstock to study the hydrodeoxygenation mechanism of converting terpenoid to produce alkane. From the preliminary data, we found that the effective deoxygenation of cyclic monoterpenoids for the production of alkanes will undergo three main steps: C-O ring opening, dehydration, and hydrogenation. Tandem catalytic process in bi-phasic system were designed for hydrodeoxygenation of cyclic ethers to produce cyclic alkanes in a "one-pot" reaction. The conversion of 1,8-cineole reached 99% with a 99% selectivity to the desired cycloalkanes after only 1 hour at 120ºC. Moreover, the gumweed biocrude was converted to saturated alkanes in BiTCP at 240ºC after 1 hour. Most of the oxygen heteroatoms have been removed under this reaction system according to liquid products analysis via GC/MS. In addition, the products were easily separated into two immiscible phases spontaneously after the reaction. In a separate, but related project, we also investigated the production of biofuels through pyrolysis of the acetone extract, labeled biocrude. When this material was heat to approximately 400 degrees centigrade, a reaction occured that produced a dark oil that distilled between 110 degrees centigrade up to 250 degrees centigrade. The 45% conversion of the biocrude to this oil produced a product that was separated into three fractions, including a low boiling mixture from ambient to 140 degrees centigrade, and midrange fraction to 190 degrees centigrade and a high boiling range from 190-240 degrees centigrade. The two compounds that were the largest single constituents in the oils were a tri and tetramethyl decalin, which have boiling points in the diesel/jet fuel range. Further analysis of the oils revealed issues with acidity values, the presence of water in the distillate, and narrowing the range of product distribution. Each of these issues can be resolved, however, and will be examined over the next year. Pyrolysis of the plant material following drying was also examined, and produced a similiar quantity of fuel oil, although the distribution of products was different. While direct pyrolysis of the plant material eliminates the requirement of extraction, it also converts the potenially useful feed product to a carbonized version that has not feed value. 3. Develop suitable agronomic methods for efficient production of gumweed and rabbitbrush as a source of extractable terpenoids that can be converted to fuels, as well as improve methods for production of byproducts, particularly rubber and useful bioproducts: Efforts on gowing grindelia commercially proceeded, and we demonstrated that the best production of dried biomass was on the closest spacing examined of 15 cm, which produced 14,900 kg/ha, which was equivalent to 1860 kg/ha of biocrude. The average production for the 2014 harvest was 11,800 kg/ha, with equivalent biocrude production of 1250 kg/ha. When examining the effect of irrigation of the second year of the bienniel plant, no significant difference was observed for plants that received two irrigations of 15 cm/irrigation and no irrigation. This observation demonstrates that grindelia can be grown in low water conditions, and utilize only the meteoric water. Field germination of seeds of grinelia continues to be erratic, and the successful plot studies were completed only with greenhouse germinated seeds, followed by transplanting the seedlings into the field plots. For the rabbitbrush studies, several extraction methods have been evaluated to determine the most efficient extraction method. This work will be continued in the next year.

Publications

• Type: Journal Articles Status: Accepted Year Published: 2015 Citation: "Hydrothermal Carbonization (HTC) and Pelletization of Two Arid Land Plants Bagasse for Energy Densification" Author(s): Reza, Toufiq; Yang, Xiaokun; Coronella, Charles; Lin, Hongfei; Hathwaik , Upul; Shintani, David; Neupane, Bishnu; Miller, Glenn Accepted for publication in: ACS Sustainable Chem. Eng.,
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: "Catalytic Upgrading Biocrude from Grindelia Squarrosa to Jet Fuels through Aqueous Phase Hydrodeoxygenation" on the 249th AIChE Conference, Salt Lake City, UT. Aug. 11 2015. Xiaokun Yang, Marcus V. Pereira, Hongfei Lin, Bishnu Neupane, M. Toufiq Reza, Charles J. Coronella, Glenn C. Miller, David Shintani, Simon Poulson.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Arid Lands Biofuels: A Case Study of Grindelia squarrosa, Bishnu Neupane and Glenn Miller National Biodiesel Conference & Expo, Jan. 19  22, 2015 Fort Worth Convention Center, TX

Progress 12/01/13 to 11/30/14

Outputs
Target Audience: The target audience for this reseqrch is the agricultural community in the arid states of the west. Another community is the general scientific community interested in biofuel and biomaterial production, and the conversion of these products to useful biofuels and bioproducts. Changes/Problems: There are no significant changes in the proposed work. What opportunities for training and professional development has the project provided? Graduate and undergraduate students were used for most of this project, either in chemical engineering or in agriculture. As such the two primary graduate students (both Ph.D. students) have gained extensive experience on utilizing catalytic methods, improved extraction techniques and agronomic production of biofuel and biomaterial plants.. How have the results been disseminated to communities of interest? Two poster presentations were made at national biofuel conferences, and three papers (on catalytic processes, gumweed production and rabbitbrust prodution) are being prepared. During September of 2014, an agricultural field day was held at Main Station Farm and the interested agricultural and non-agricultural communities were given tours of the gumweed production facilities and aspects of the entire project were presented. Three articles for publication are presently in draft stage. What do you plan to do during the next reporting period to accomplish the goals? As described in the original proposal, further activities to accomplish the goals of the project will be continued. 1a. Further work on refining the SCF extractions will be continued. Other extraction techniques are also presently being examined with a goal of reducing costs and solvent consumption. Creation of pellets and torrefaction of the pellents will be examined to potentially utilize the begasse for energy production. 2. To fulfill the project goals, the analysis of aqueous phase, gas phase and solid phase products in addtion to the oil phase is necessary to close the carbon balance. Furthermore, new catalysts synthesis methods to produce bi-functional catalysts with tunable metal size and catalytic activity and selectivity will be developed and synthesized to maximize the yields of desired jet fuel range hydrocarbons with two or three cyclic rings. Biocrude and other model compounds will be used as the feedstocks and the appropriate reaction conditions will be developed to deliver high yield and high quality of jet fuel components. 3. Further production data will be obtained on gumweed grown in field tests. We will specifically examine methods to germinate seeds in the field to allow this crop to be economically grown. For data on production of biocrude and more specifically, grindelic acid will be developed. During the next harvest, selection of highest production plants will be conducted. Alternative uses of grindelic acid will be examined, particularly as a replacement for abietic acid. 4. Increased focus will be put on rubber and resin production from rabbitbrush. During 2014, we collected wild seeds and they will be germinated and planted in agricultural field plots, although native stands of rabbitbrush will be utilized for the next two years to determine rubber production and extraction methods.

Impacts
What was accomplished under these goals? The progress accomplished under these goals is the following. I. Experimental Plan for ScCO2 Extraction of Gumweed In this study, a 2L Parr batch reactor, model 4526 (Moline, IL) was purchased and used as reaction vessel. \Maximum pressure and temperature of this reactor is rated as 200 bar and 350 °C, respectively. In a typical SFE experiment, 10-50 g of unextracted grindelia was fed into the reactor. Dry ice was used as CO2 source for this experiment. About 500 g excess crushed dry ice, based on the operating condition of the specific experiment, was fed into the reactor. The reactor is next closed and heater was turned on. A Parr heater (1100 W, calrod type) was used to heat the vessel and a Parr PID controller was used to control the reactor temperature. It can be noted that starting temperature was -52 °C. For this study, we have used extraction temperature 40-90 °C, density 200-600 kg/m3, and extraction time 30 min-2h. It usually takes 30-60 min to reach the desired temperature. At the end of reaction period, the heater was turned off and the reactor was quenched in an ice-water bath and was then vented into the hood through a chiller trap (made by dry ice), to ensure not to bleed extracted volatiles. The reactor was opened after the pressure was reduced to ambient and all CO2 had escaped. The solid residue was collected, and the reactor was rinsed by acetone to collect the extracted fraction from the reactor wall. The solid residue was then dried and stored in ziplock bags for further treatment and characterization. Meanwhile, extracts are analyzed by GC-MS to detect the extracted chemical species and then by HPLC for quantification. II. Catalyst activities for converting grindelic acid to biofuel. To fulfill the specific objectives 2.1, we synthesized multifunctional catalysts with different metals on different solid acid supports catalysts aiming at deoxygenation over transition metals Pd, Ni and Cu and C-C bond cracking. Catalyst screening including 1% Pd/ZrO2, 1% Pd/W-ZrO2, 1% Pd/Zeolite Y, 10% Ni/Zeolite Y, 10% Cu/Zeolite Y was carried out. Different catalytic performance of the house-made catalysts toward the aqueous phase reduction of grindelia extract to produce hydrocarbon fuels in jet fuel range was compared. Comparison experiments of each mono-functional catalyst showed different results. At first, we used a very small amount (0.2g) of grindelia biocrude as the feedstock, ran the reaction for 15 hours under 240C in 400 psi H2 conditions. Compared to blank experiment without adding any catalyst, the products color after adding W-ZrO2 as catalyst changed from brown to light yellow, which can be ascribed to the decomposition of some large molecules. For products reacted over Pd/AC, we can see that the color turned to clear. This phenomenon showed us that the reactions proceeded under different mono-functional catalysts, leading us to further study the bi-functional catalyst. For bi-functional catalysts, we found that both the oil phase weight and O content varies depend on different transition metals and supports. According to aviation fuel specification, the acid number in Jet-8 should be lower than 0.015 mg KOH/g which can be reflected by oxygen content percent. For grindelia extract, 19% oxygen content in the oil phase need to be removed as much as possible to reach a high quality of jet fuel products. After comparison among 1% Pd, 10% Ni and 10% Cu on zeolite Y, we found that both 1% Pd and 10% Ni on zeolite Y support can lower the O content in the oil phase from 19% to ~5% after 1 hour hydrothermal reaction and 56~68% oil phase can be collected back. By comparing Pd on different supports including zeolite Y, ZrO2 and W-ZrO2, although the acid strength of W-ZrO2 is lower than zeolite Y according to chemisorption analyzer, but W-ZrO2 gave the lower O content and slightly higher oil phase weight than zeolite Y, which might occur because of the bulk W-ZrO2 is less likely to be coked than porous zeolite Y structure. To fulfill the objective 2.2 and 2.3, we set up methods for GC-MS and GC-FID to examine the oil phase product distribution and grindelic acid conversion.. When the reaction temperature reached 200C, almost all grindelic acid was converted to lower molecular weight compounds, which still kept the tricyclic ring structure but with only one oxygen atom in most of the structures. By increasing the reaction temperature to 220C and 240C, grindelic acid was 100% converted, which was also confirmed by GC-FID quantification analysis. More weight of the oil phase can be collected back after hydrothermal catalytic reaction with reaction temperature increase. And, less O content stayed in the oil phase at higher temperature. It can be concluded that with reaction time increases, non-polar products in the oil phase increased until 6 hours, it will reach to plateau, although the total oil phase weight percent decreased with longer reaction time. In this summary, we found that approximately half of the products were in the jet fuel carbon number ranges with a molecular formula C14H22 or C14H22O, and composed of two cyclic rings. III. Production of Gumweed Seeds were germinated in tubes inside the green house at UNR on May 2013, with approximately 80-85% successful germination by the end of 4th week. The seedlings were transplanted in Main Station Farm experimental plot at UNR in 42 different plots of size 4mx4m from late June to mid-July, and each plant was watered by drip irrigation supplying two gallons of water every week for three weeks. During 2014 four different treatments were utilized for the plants established in 2013. These included (1) fertilizer and irrigation(F+I); (2) fertilizer only(F only); (3) irrigation only (I only); or (4) no fertilizer or irrigation (N). The plants spacings were 15 inches, 12 inches, 9 inches and 7.5 inches apart based on random selection in all different conditions. For the fertilization plots, 3 grams of chemical fertilizer per plant (NPK: 16-4-8) plus micronutrients. Similarly, selected plots were supplied with drip irrigation twice with about 4 gallons to each plant on the last week of May and the third week of June 2014. The harvesting was done in the last week of July when most of the plants had milky white sticky head in their flowers with some having more mature yellow flowers. Once the harvesting was completed in 2014, the plant biomass was dried, weighed and ground separately. Two methods of harvesting were utilized. The first utilized a harvest of the milky white flowers (top 20-30 cm), and the second cut the entire plant down. Second harvests from regrowth were conducted (data not shown), and the total biomass production from the summed first and second harvests from both harvest treatments was similiar, although the biocrude production has not yet been completed. The plots extablished during 2013, which were harvested in 2014 were on better quality soil plots that the plants planted in 2012 and harvested in 2014, and showed an increase in production per plot of approximately 20-30%. Conclusions There was no significant trend (increasing or decreasing) in weight of biomass of harvest of the top 20-30cm only for the plots of with differing numbers of plants. However, the biomass per plant was higher in the plots with fewer plants (wider planting distance). For the whole biomass harvest, there was generally an increasing amount of total biomass per plot as the number of plants were higher, and the biomass per plant decreased as the number of plants in the plot increased. There is no differences between the average production of the harvest in F+I, F only, I only and N plot (applied in 2014). This suggests that there is no substantial difference between in the production of biomass of gumweed whether there was additional nutrient and irrigation supplied, and is potentially very important for growth of this arid lands crop.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: "Arid lands biofuels" A poster presentation at the National American Chemical Society Meetings in Dallas, TX, March 16-20,paper number: 285 DIVISION: ENFL: Division of Energy and Fuels SESSION: Advances in Energy and Fuels Processes, Systems, Materials and Utilization SESSION START TIME: March 18, 2014, 2:00 pm PRESENTATION FORMAT: Poster
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: "Preparation of the reference standards for Arid Lands Biofuel  a case study of Grindelia squarosa" A poster presentation at the National Biodiesel Conference & Expo, Jan. 20  23, 2014 in San Diego CA.