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The economic viability of the biofuel industry could be improved by adding a high-value revenue stream for biomass supply chains: bioderived composites for the rapidly expanding large-scale additive manufacturing industry (i.e., 3D printing). Using fibrillated fibers derived from biomass (e.g.

A series of NiO/HZSM-5 catalysts were used to convert alkali lignin to hydrocarbon biofuels in a two-stage catalytic pyrolysis system. The results indicated that all NiO/HZSM-5 catalysts reduced the content of undesirable phenols, furans, and alcohols of the biofuel compared to non-catalytic treatment. The NiO/HZSM-5 catalyst with the lowest amount of NiO generated the highest biofuel yield in all catalytic treatments, and it also produced biofuel with the highest content of hydrocarbons. The emission of carbon oxides (CO and CO2) increased in the treatments with higher-NiO loading HZSM-5 due to the redox reaction between NiO and the oxygenated compounds in the bio-oil. Ni2SiO4 was generated in the used NiO/HZSM-5 catalysts during the high-temperature pyrolysis process.

Hydroprocessing of carinata oil over an Al2O3 supported Mo-Zn catalyst in a batch reactor at 350 °C with an initial H2 pressure of 300 psi was carried out to produce hydrocarbon biofuel. A series of Mo-Zn/Al2O3 catalysts with different Zn/Mo molar ratios (0, 1, 2, 3, ∞) were prepared and characterized using XRD, FT-IR, BET and TEM. The effects on the physicochemical properties and yield of products from using no catalyst and Al2O3 based catalysts were discussed. The introduction of Mo and/or Zn did not change the crystalline structure of Al2O3. The combining of Mo and Zn on Al2O3 improved catalytic performance and was helpful to improve some of the physicochemical properties of hydrocarbon biofuel including hydrocarbon content, moisture content, density, total acid number and higher heating value (HHV). The catalyst which exhibited the best catalytic performance had a Zn/Mo molar ratio of 2:1. At the 2:1 ratio of Zn/Mo, the hydrocarbon biofuel produced displayed the highest hydrocarbon content (81.05%) and the lowest moisture content, and the highest sum content of CO and CO2 in the gas produced. The introduction of Mo and Zn on Al2O3 was helpful for the hydroprocessing of carinata oil for hydrocarbon biofuel production.

Ni/HZSM-5 catalysts were prepared using the impregnation method. The HZSM-5 and impregnated Ni/HZSM-5 catalysts were characterized by Brunauer–Emmett–Teller and X-ray diffraction. The HZSM-5 and Ni/HZSM-5 catalysts were used for prairie cordgrass (PCG) thermal conversion in a two-stage catalytic pyrolysis system. The products contained gas, bio-oil, and bio-char. The gas and bio-oil were analyzed by gas chromatography and gas chromatography–mass spectrometry separately. Higher heating values and elemental composition of bio-char were determined. The results indicated that 12% Ni/HZSM-5 treatment yielded the highest amount of gasoline fraction for hydrocarbons and showed a robust ability to upgrade bio-oil vapor.

As nonfood oilseed varieties are being rapidly developed, new varieties may affect agricultural production efficiency and life-cycle assessment results. Current, detailed feedstock production information is necessary to accurately assess impacts of the biofuel life-cycle. The life-cycle impacts of four nonfood oilseeds (carinata [ L. Braun], camelina [ L. Crantz], canola or rapeseed [ L.], and sunflower [ L.]) were modeled using Argonne National Laboratory's GREET model to compare feedstocks for renewable biojet production using cold-press oil extraction. Only feedstock-related inputs were varied, allowing isolation of feedstock influence. Carinata and camelina performed slightly better than other oilseed crops at most product stages and impact categories as a result of current, low-input agricultural information and new feedstock varieties. Between 40 to 50% of SO and NO emissions, ∼25% of greenhouse gas (GHG) emissions, and ∼40% of total energy consumption for the biojet production impact occurred during feedstock production. Within the first standard deviation, total well-to-tank emissions varied between ∼13% (GHG) and ∼35% (SO) for all feedstocks emphasizing the importance of accurate agricultural production information. Nonfood oilseed feedstock properties (e.g., oil content, density) and agricultural management (e.g., fertilization, yield) affect life-cycle assessment results. Using biofuels in feedstock production and focusing on low-impact management would assist producers in improving overall product sustainability.

Upgrading pyrolysis oil by hydrodeoxygenation (HDO) is a promising route for the production of advanced biofuels. The proper reaction conditions and catalysts are important for the success of this process. Previously our research group investigated the ratio of Zn and Pd on the synergistic effect for HDO bio-oil upgrading. This present research focuses on determining the optimal reaction conditions for HDO conversion of pyrolysis oil produced from pine sawdust. Temperatures of 150, 200 and 250 °C and hydrogen pressures of 1.38, 2.76 and 4.14 MPa were evaluated. Syngas, liquids and coke were the primary products evaluated. Syngas was characterized using a Gas chromatography (GC). The liquids were characterized using a Gas chromatography–mass spectrometry (GC–MS). Increasing reaction temperature resulted in increased coke yields. Treatment at 250 °C and 1.38 MPa resulted in the highest hydrocarbon content (6.06%). The treatment at 200 °C and 1.38 MPa produced the largest amounts of hydrocarbons in C6–C12 range (5.07%). The physicochemical characterizations further support the GCMS results. Syngas analysis revealed that higher hydrogen pressure leads to increased hydrogen consumption and results in more oxy-compounds conversion to hydrocarbons. The syngas analysis also supports the liquid analysis result.

Catalytic cracking of camelina oil over Zn/ZSM-5 catalyst in a fixed-bed tubular reactor was investigated. An optimization study on the catalytic cracking conditions based on nine well-planned orthogonal experiments was carried out. Three main operation conditions including reaction temperature, liquid hourly space velocity and oil extraction press frequency were studied to examine their effects on the yield and quality of hydrocarbon biofuel produced. Characterization of the catalyst, hydrocarbon biofuel and non-condensable gas was conducted. There was no significant difference between the bulk structures of fresh Zn/ZSM-5 and used Zn/ZSM-5. Small ZnO particles dispersed well on the parent ZSM-5. Hydrocarbon biofuel contained 65.18% hydrocarbons and its properties including dynamic viscosity, density and higher heating value were improved after upgrading, compared to camelina oil. It was found that the oil extraction press frequency was the most important factor and liquid hourly space velocity was the least important factor for the hydrocarbon biofuel production. In addition, the optimum conditions for camelina oil upgrading were a combination of reaction temperature of 550 °C, a liquid hourly space velocity of 1.0 h −1 and an oil extraction press frequency of 15 Hz.

Cracking of camelina oil over non-catalyst and ZSM-5 catalyst doped with different Zn concentrations (0, 10, 20 and 30 wt.%) in a fixed-bed reactor was investigated. The fresh and used catalysts were characterized using XRD, FT-IR, BET and TEM. Characterizations of the produced hydrocarbon biofuel, distillation residual and non-condensable gas were carried out. The effect of non-catalyst and catalyst on the physicochemical properties and yield of products was discussed. The results showed that the introduction of Zn did not change the zeolite crystalline structure and ZnO might deposit on the external surface and/or inside the pores of the support ZSM-5. After upgrading, hydrocarbon biofuel had a lower viscosity, lower density, higher heating value (HHV) and higher water content than raw camelina oil. The optimum Zn concentration to ZSM-5 was 20 wt.%, at which the highest hydrocarbon biofuel yield and comprehensively the best quality were obtained. Compared to non-catalytic cracking of camelina oil, the loading of Zn to ZSM-5 could improve some physicochemical properties of the hydrocarbon biofuel. In addition, the loading of Zn to ZSM-5 could facilitate the chemical reactions such as decarbonylation and dehydrogenation.

Catalytic cracking of carinata oil over fresh and regenerated Zn/Na-ZSM-5 catalyst in a fixed-bed reactor at 450 °C was carried out to produce hydrocarbon biofuel. The effect of the fresh and regenerated Zn/Na-ZSM-5 on the hydrocarbon biofuel’s quality and yield was discussed. Characterization of the catalyst, hydrocarbon biofuel and gas were carried out. The hydrocarbon biofuel yield obtained over regenerated Zn/Na-ZSM-5 increased but the coke yield and distillation residual yield decreased, compared to fresh Zn/Na-ZSM-5. The regeneration of Zn/Na-ZSM-5 had a minor influence on the density of the hydrocarbon biofuel, but the higher heating value (HHV) decreased, and the viscosity and acid value increased over regenerated Zn/Na-ZSM-5. The regeneration of Zn/Na-ZSM-5 reduced the decarboxylation, decarbonylation and dehydrogenation of carinata oil, which caused the lower content of CO2, CO, H2 and light hydrocarbons (C1–C5). A preliminary test of the distillation residual mixture upgrading over fresh Zn/Na-ZSM-5 was performed, suggesting that the distillation residual mixture could be recycled for further upgrading. The produced gas including H2, CO and light hydrocarbons might be reused as syngas for ether power generation or production of value chemicals.

The performance of catalytic tri-reforming under industrially relevant situations (e.g., pellet catalysts, pressurized reactor) was investigated using surrogate biogas as the feedstock. Tri-reforming using Ni/Mg/Ce0.6Zr0.4O2/Al2O3 pellet catalysts was studied in a bench scale fixed-bed reactor. The feed molar ratio for CH4:CO2:air was fixed as 1.0:0.70:0.95. The effects of temperature (800–860°C), pressure (1–6 bar), and H2O/CH4 molar feed ratio (0.23–0.65) were examined. Pressure has substantial impact on the reaction and transport rates and equilibrium conversions, making it a key variable. At 860°C, CO2 conversion increased from 4 to 61% and H2/CO molar ratio decreased from 2.0 to 1.1 as the pressure changed from 1 to 6 bar. CO2 conversion and H2/CO molar ratio were also influenced by the temperature and H2O/CH4 molar ratio. At 3 bar, CO2 conversion varied between 4 and 43% and the H2/CO molar ratio varied between 1.2 and 1.9 as the temperature changed from 800 to 860°C. At 3 bar and 860°C, CO2 conversion decreased from 35 to 8% and H2/CO molar ratio increased from 1.7 to 2.4 when the H2O/CH4 molar ratio was increased from 0.23 to 0.65. This work demonstrates that the tri-reforming technology is feasible for converting biogas under scaled-up conditions in a fixed-bed reactor.

In this study, the pine sawdust thermal conversions over HZSM-5 catalyst were carried out under different reaction temperatures in a two-stage catalytic pyrolysis reactor. Higher temperatures in the catalytic reactor tended to decrease the yield of bio-oil and change the component of bio-oil. The results from the gas chromatography–mass spectrometry (GC–MS) analysis showed that the pyrolysis reaction at 500 °C and catalytic reaction at 500 °C treatment obtained the highest hydrocarbon content (58.63%) and the highest C 8 –C 12 content (48.03%) in the oil phase of the bio-oil. The X-ray diffraction (XRD) and selected-area-electron-diffraction (SEAD) characterization showed that the distortion of the ZSM-5 zeolite lattice occurred before and after use. The Brunauer–Emmett–Teller (BET) characterization indicated that the formation of coke increased as the catalytic temperature rose. The physical characterization of bio-oils, such as water content, density, viscosity, pH, and higher heating value (HHV) further demonstrated that HZSM-5 catalyst was beneficial in achieving low viscosity and higher HHV bio-oils. All the results suggest that the two-stage catalytic pyrolysis reactor with HZSM-5 catalyst has a great potential for achieving advanced biofuel.

. Catalytic cracking of carinata oil over Zn/Na-ZSM-5 catalyst in a fixed-bed reactor at 450 °C was carried out to produce hydrocarbon biofuel. The effect of Zn/Na-ZSM-5 catalyst on the yield and quality of the hydrocarbon biofuel was discussed. The yield of hydrocarbon biofuel, distillation residual, coke and gas was analyzed. Characterization of the hydrocarbon biofuel including density, moisture content, viscosity, higher heating value (HHV) and main components was carried out. In addition, the components of gas were analyzed. The yield of hydrocarbon biofuel and gas was 43.66% and 18.84%, respectively. After the carinata oil upgrading, some properties of the hydrocarbon biofuel including density, viscosity and HHV were improved. The hydrocarbon biofuel contained more than 90% hydrocarbons while it still contained a small amount of oxygenated compounds such as aldehyde, ether and ester. The produced distillation residual might be recycled for further catalytic cracking to increase the hydrocarbon biofuel yield. The produced gas including H 2 , CO and light hydrocarbons might be reused as syngas for ether power generation or production of value chemicals.

Catalytic fast pyrolysis (CFP) is proven one of the most promising processes for effectively converting biomass to liquid advanced biofuels. The yield and quality of biofuels are depended on biomass species, reactor type, operating conditions (such as temperature, pressure, heating rate, etc.) as well as the presenting of appropriate catalysts. Based on current CFP research, a hypothesis of biomass precision pyrolysis was proposed. A novel accurate control catalyst fast pyrolysis (ACCFP) reactor was invented and tested for exploration of biomass precision pyrolysis possibility. Various lignocellulosic biomass materials such as switchgrass, corn stover, prairie cordgrass, and pine sawdust were tested. The effects of reaction temperature, pressure, and heating rate on pyrolysis products (bio-oil, bio-char, and biosyngas) were investigated. ZSM-5 combined with various metal catalysts were applied in the ACCFP process. The pyrolysis products (bio-oil, bio-char, and biosyngas) produced were characterized for their physicochemical properties such as total acid number (TAN), water content, density, pH value, viscosity, higher heating value, and/or chemical composition. The results indicated that it is possible to accurately control CFP processing conditions to produce target bioproducts, which may lead to biomass precision pyrolysis. Compared to conventional pyrolysis, the ACCFP process could improve pyrolysis products yields and quality, such as greatly reducing oxygen content in the bio-oils produced. Although further research is needed, the study confirms that precision biomass pyrolysis may be an effective pathway for converting lignocellulosic biomass to advanced biofuels or chemicals.

To address the issues of greenhouse gas emissions associated with fossil fuels, vegetable oilseeds, especially non-food oilseeds, are used as an alternative fuel resource. Vegetable oil derived from these oilseeds can be upgraded into hydrocarbon biofuel. Catalytic cracking and hydroprocessing are two of the most promising pathways for converting vegetable oil to hydrocarbon biofuel. Heterogeneous catalysts play a critical role in those processes. The present review summarizes current progresses and remaining challenges of vegetable oil upgrading to biofuel. The catalyst properties, applications, deactivation, and regeneration are reviewed. A comparison of catalysts used in vegetable oil and bio-oil upgrading is also carried out. Some suggestions for heterogeneous catalysts applied in vegetable oil upgrading to improve the yield and quality of hydrocarbon biofuel are provided for further research in the future.

Because not conflict with human and animal food resources, non-food vegetable oils are promising sources for developing liquid advanced biofuel. Directly upgrading non-food vegetable oils to hydrocarbon fuels is likely offering reasonable profit margin for bio-jet fuel production. The sunflower oil extracted from residues that were produced in sunflower seed de-hulled processing is inedible due to its quality not meeting food standards. Genetically modified sunflower grown on margin lands can also provide one possible non-food source for sustainable biofuel production source since it doesn’t compete with the use of arable lands. Sunflower oils produced from those non-food sources were cracked on ZSM-5 catalysts in a fixed-bed reactor at three temperatures, 450 °C, 500 °C, and 550 °C. Characterization of the upgraded sunflower oils, advanced hydrocarbon fuel and distilled residual fuel, including pH value, density, water content, viscosity, heating value, and fatty acid profile, was carried out. The composition of non-condensable gases generated during the catalytic cracking process was also analyzed. The effect of the reaction temperatures on the upgraded sunflower oils’ yield and quality was discussed. The results showed that reaction temperatures affected the yield and properties of upgraded sunflower oils. The highest yield of advanced hydrocarbon fuel from raw sunflower oils was 21.1% at 550 °C. Upgraded sunflower oils were a mixture of un-cracked oils and hydrocarbons. After distillation, the advanced hydrocarbon fuel had lower viscosity, moisture content and density. The non-condensable gases contained C 1 – C 5 light hydrocarbons, H 2 , CO, CO 2 , etc. The reaction temperatures had significant effect on the concentrations of these compounds during catalytically cracking sunflower oils.

Biomass is known as the only source for production of renewable liquid transportation biofuels. Lignocellulosic biomass has an advantage over other biofuel feedstocks, such as corn starch, soybeans, and sugar cane, because it can be produced quickly and at significantly low cost but not to compete to food crops. Nonetheless, transportation and storage are still big issues for sending lignocellulosic biomass feedstocks to bio-refinery facility to be converted into biofuels due to their low bulk density, high moisture, and biodegrading properties. The presenting study was trying to address those issues by torrefaction pretreatment. Torrefaction of corn stover, switchgrass, and prairie grass was carried using a lab scale batch reactor. The reactor was heated up to the selected temperature (250°C, 300°C, or 350°C) and kept at the final temperature for a period of 3 hours. The effect of raw materials and temperatures on the properties of the torrefied products (solid bio-char, liquid bio-oil, and gaseous syngas) was analyzed. These products were characterized with heating value, pH value, moisture content, etc. The heating values of bio-char increased with temperature of torrefaction while the yields on a weight basis decreased. The bio-chars produced have hydrophobic properties and higher heating values than the raw materials.

Biofuel is an alternative to fossil fuels with benefits of less impact on environment, national energy security, and rural economic growth. Fuel ethanol and biodiesel industries have grown fast all over the world in recent years. However, very fewer biofuels have been applied in aviation fuels because there are still many technical challenges for biofuels meeting the strict requirement of aviation fuels, such as low temperature, fluidity, high energy density, compatibility with materials of aircraft engine, etc. This study is aiming on exploring a sustainable pathway of jet fuel production from non-food vegetable oils. The Jet fuels produced could be applied in commercial airplanes or navy and air force aircrafts. Oil extraction from oilseeds is a critical step in the pathway. The tests of oil extraction from non-food sunflower seeds, sunflower meats, and fine sunflower meats were conducted by using a cold press in the study. The frequency controlling screw rotating speed of the cold press and processing temperature were discussed. The characterization of the raw oils produced was carried out. The effects of frequency and temperatures on oil properties such as density, pH value, viscosity, moisture content, CHNO contents, and organic compounds were examined. Oil remained in the processing residual meals was also determined by using solvent extraction method. The results show that higher oil extraction efficiency was obtained at related lower frequency. Processing temperatures had significant effects on the cold press performance. When the temperature was higher than 90°C or lower than 40°C, the cold press couldn’t work properly. The highest oil extraction efficiency for sunflower seeds, sunflower meats and fine sunflower meats in the tests were 75.67%, 89.74% and 83.19% respectively. Though further study is needed for the improvement of processing cost and efficiency, cold press could be one of efficient methods for oil extraction from various non-food oilseeds.

The massive consumption of fossil fuels and associated environmental issues are leading to an increased interest in alternative resources such as biofuels. The renewable biofuels can be upgraded from bio-oils that are derived from biomass pyrolysis. Catalytic cracking and hydrodeoxygenation (HDO) are two of the most promising bio-oil upgrading processes for biofuel production. Heterogeneous catalysts are essential for upgrading bio-oil into hydrocarbon biofuel. Although advances have been achieved, the deactivation and regeneration of catalysts still remains a challenge. This review focuses on the current progress and challenges of heterogeneous catalyst application, deactivation, and regeneration. The technologies of catalysts deactivation, reduction, and regeneration for improving catalyst activity and stability are discussed. Some suggestions for future research including catalyst mechanism, catalyst development, process integration, and biomass modification for the production of hydrocarbon biofuels are provided.

Individually, sunflower oil produced from inedible sunflower seeds with hulls and sunflower meats without hulls were catalytically cracked over the ZSM-5 catalyst in a fixed-bed reactor at three reaction temperatures (450 °C, 500 °C, and 550 °C). Characterizations of hydrocarbon biofuel, distillation residual, and non-condensable gas were carried out. The reaction temperature on the hydrocarbon biofuel yield and quality from sunflower seed oil and sunflower meat oil were discussed and compared. In addition, a preliminary cost analysis of the sunflower seed dehulling was carried out. The results showed that the highest hydrocarbon biofuel yield was obtained from upgrading sunflower meat oil at 500 °C. The highest meat hydrocarbon biofuel yield was 8.5% higher than the highest seed hydrocarbon biofuel yield. The reaction temperature had a significant effect on the distribution of non-condensable gas components. Furthermore, the reaction temperature affected the yield and properties of hydrocarbon biofuel. The unit cost of producing sunflower meat oil was lower than that of producing sunflower seed oil. Comprehensively, sunflower meat could be a more economical feedstock than sunflower seed to produce hydrocarbon biofuel.