ABSTRACT In this study, the pine sawdust thermal conversions over HZSM-5 catalyst were carried ou... more ABSTRACT 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 C8–C12 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.
ABSTRACT Mo–Cu/HZSM-5 catalysts for pine sawdust thermal conversion were prepared using an impreg... more ABSTRACT Mo–Cu/HZSM-5 catalysts for pine sawdust thermal conversion were prepared using an impregnation method. The Mo–Cu/HZSM-5 catalysts and HZSM-5 were characterized by Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD) and transmission electron microscopy (TEM). All characterization results indicated that the introduction of CuO is beneficial to the dispersion of MoO3 in the HZSM-5. Combined with the two-stage catalytic pyrolysis system, the Mo–Cu/HZSM-5 catalysts were used for pine sawdust thermal conversion. The products included gas, bio-oil and bio-char. The gas was analyzed by Gas chromatography (GC). Gas chromatography–mass spectrometry (GC–MS) was used to identify the compounds in bio-oils. The water content, higher heating value (HHV) and viscosity of bio-oils were measured. The HHV and elements of bio-char were determined. The results indicated that Mo(3%)–Cu(3%)/HZSM-5 treatment yielded the highest amount of C6–C12 hydrocarbons, showed a robust ability to convert methane in the gas to bio-oil, and displayed no significant difference in the properties of bio-char when compared to different treatments in the same pyrolysis conditions.
ABSTRACT Catalytic cracking of camelina oils to hydrocarbon fuels over ZSM-5 and ZSM-5 impregnate... more ABSTRACT Catalytic cracking of camelina oils to hydrocarbon fuels over ZSM-5 and ZSM-5 impregnated with Zn2+ (named bifunctional catalyst) was individually carried out at 500 °C using a tubular fixed-bed reactor. Fresh and used catalysts were characterized by ammonia temperature-programmed desorption (NH3-TPD), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and nitrogen isothermal adsorption/desorption micropore analyzer. The effect of catalysts on the yield rate and qualities of products was discussed. The loading of Zn2+ to ZSM-5 provided additional acid sites and increased the ratio of Lewis acid site to Brønsted acid site. BET results revealed that the surface area and pore volume of the catalyst decreased after ZSM-5 was impregnated with zinc, while the pore size increased. When using the bifunctional catalyst, the pH value and heating value of upgraded camelina oils increased, while the oxygen content and moisture content decreased. Additionally, the yield rate of hydrocarbon fuels increased, while the density and oxygen content decreased. Because of a high content of fatty acids, the distillation residues of cracking oils might be recycled to the process to improve the hydrocarbon fuel yield rate.
The biochar source-processing combination provides a rich diversity of biochars to evaluate for s... more The biochar source-processing combination provides a rich diversity of biochars to evaluate for soil amendment use and determines the persistence of biochar within the soil. The potential of biochar as a soil amendment is dependent on its physical and chemical properties. Biochar interacts with other soil components such as ions, organic matter, and clay. Biochar properties range from acidic to alkaline depending on source and manufacturing process. The challenge is to identify a biochar source and processing combination that will optimize its efficiency as a soil amendment and still allow utility of the biomass as a bioenergy production. Biochar application has been shown to improve soil physical, chemical, and biological properties. Application of biochar has been reported increase available water, build soil organic matter, enhance nutrient cycling, lower bulk density, act as a liming agent, and reduce transfer of pesticides and nutrients to surface and ground water. The benefits...
ABSTRACT In this study, modified clean fractionation process was optimized for prairie cordgrass,... more ABSTRACT In this study, modified clean fractionation process was optimized for prairie cordgrass, with usage of alternative organic constituent –ethyl acetate. Other constituents of the solvent mixture included ethanol and water. Clean fractionation solvent was used in different proportions of the constituents. Process efficiency was determined by lignin recovery, solvent composition, as well as time and temperature applied to each sequential process. Glucose yield during enzymatic hydrolysis and overall pretreatment were calculated. Optimal conditions (125℃, 37 min, with the solvent composition of ester:ethanol:water = 32.5:22.5:45) yielded a 20% lignin recovery, 38% glucose yield during enzymatic hydrolysis and 26% xylose recovery in aqueous fraction. Citation: Cybulska I, Lei H W, Julson J, Brudecki G. Optimization of modified clean fractionation of prairie cordgrass. Int J Agric & Biol Eng, 2012; 5(2): 42-51.
Non-edible sunflower oils that were extracted from sunflower residual wastes were catalytically c... more Non-edible sunflower oils that were extracted from sunflower residual wastes were catalytically cracked over a ZSM-5 catalyst in a fixed-bed reactor at three different reaction temperatures: 450°C, 500°C and 550°C. The catalyst was characterized using XRD, FT-IR, BET and SEM. Characterizations of the upgraded sunflower oils, hydrocarbon fuels, distillation residues and non-condensable gases were carried out. The effect of the reaction temperature on the yield and quality of liquid products was discussed. The results showed that the reaction temperature affected the hydrocarbon fuel yield but had a minor influence on its properties. The highest conversion efficiency from sunflower oils to hydrocarbon fuels was 30.1%, which was obtained at 550°C. The reaction temperature affected the component content of the non-condensable gases. The non-condensable gases generated at 550°C contained the highest content of light hydrocarbons (C1C5), CO, CO2 and H2. Compared to raw sunflower oils, the...
The tentative connection between the biochar surface chemical properties and their influence on m... more The tentative connection between the biochar surface chemical properties and their influence on microbially mediated mineralization of C, N, and S with the help of enzymes is not well established. This study was designed to investigate the effect of different biomass conversion processes (microwave pyrolysis, carbon optimized gasification, and fast pyrolysis using electricity) on the composition and surface chemistry of biochar materials produced from corn stover (Zea mays L.), switchgrass (Panicum virgatum L.), and Ponderosa pine wood residue (Pinus ponderosa Lawson and C. Lawson) and determine the effect of biochars on mineralization of C, N, and S and associated soil enzymatic activities including esterase (fluorescein diacetate hydrolase, FDA), dehydrogenase (DHA), β-glucosidase (GLU), protease (PROT), and aryl sulfatase (ARSUL) in two different soils collected from footslope (Brookings) and crest (Maddock) positions of a landscape. Chemical properties of biochar materials produced from different batches of gasification process were fairly consistent. Biochar materials were found to be highly hydrophobic (low H/C values) with high aromaticity, irrespective of biomass feedstock and pyrolytic process. The short term incubation study showed that biochar had negative effects on microbial activity (FDA and DHA) and some enzymes including β-glucosidase and protease.
2013 Kansas City, Missouri, July 21 - July 24, 2013, 2013
ABSTRACT Biomass is known as the only source for production of renewable liquid transportation bi... more ABSTRACT 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.
2013 Kansas City, Missouri, July 21 - July 24, 2013, 2013
ABSTRACT Biofuel is an alternative to fossil fuels with benefits of less impact on environment, n... more ABSTRACT 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.
2012 Dallas, Texas, July 29 - August 1, 2012, 2012
ABSTRACT Catalysts play critical roles in hydrotreating and hydrocracking processes of upgrading ... more ABSTRACT Catalysts play critical roles in hydrotreating and hydrocracking processes of upgrading biomass-derived bio-oil to drop-in fuels. The selectivity and deactivate of catalysts, however, still remain biggest challenge. By using ZSM-5, aluminum, and activated carbon as supports, different catalysts made up with Ru were prepared and tested in a bio-oil upgrading process. The catalysts’ performances were investigated and compared in term of surface properties. The results showed that the ZSM-5 based catalysts got more water phase because of its highest surface acidity. The alumina changed to aluminum hydroxide in the presence of water at the reaction conditions. Activated carbon based catalysts showed good catalytic performance with more hydrocarbons and less water phase content in the upgraded bio-oil. All of upgraded bio-oils were verified by chemical analysis using a GC-MS. Nonetheless, further study for the kinetics of catalytically upgrading bio-oil is recommended.
ABSTRACT In this study, the pine sawdust thermal conversions over HZSM-5 catalyst were carried ou... more ABSTRACT 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 C8–C12 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.
ABSTRACT Mo–Cu/HZSM-5 catalysts for pine sawdust thermal conversion were prepared using an impreg... more ABSTRACT Mo–Cu/HZSM-5 catalysts for pine sawdust thermal conversion were prepared using an impregnation method. The Mo–Cu/HZSM-5 catalysts and HZSM-5 were characterized by Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD) and transmission electron microscopy (TEM). All characterization results indicated that the introduction of CuO is beneficial to the dispersion of MoO3 in the HZSM-5. Combined with the two-stage catalytic pyrolysis system, the Mo–Cu/HZSM-5 catalysts were used for pine sawdust thermal conversion. The products included gas, bio-oil and bio-char. The gas was analyzed by Gas chromatography (GC). Gas chromatography–mass spectrometry (GC–MS) was used to identify the compounds in bio-oils. The water content, higher heating value (HHV) and viscosity of bio-oils were measured. The HHV and elements of bio-char were determined. The results indicated that Mo(3%)–Cu(3%)/HZSM-5 treatment yielded the highest amount of C6–C12 hydrocarbons, showed a robust ability to convert methane in the gas to bio-oil, and displayed no significant difference in the properties of bio-char when compared to different treatments in the same pyrolysis conditions.
ABSTRACT Catalytic cracking of camelina oils to hydrocarbon fuels over ZSM-5 and ZSM-5 impregnate... more ABSTRACT Catalytic cracking of camelina oils to hydrocarbon fuels over ZSM-5 and ZSM-5 impregnated with Zn2+ (named bifunctional catalyst) was individually carried out at 500 °C using a tubular fixed-bed reactor. Fresh and used catalysts were characterized by ammonia temperature-programmed desorption (NH3-TPD), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and nitrogen isothermal adsorption/desorption micropore analyzer. The effect of catalysts on the yield rate and qualities of products was discussed. The loading of Zn2+ to ZSM-5 provided additional acid sites and increased the ratio of Lewis acid site to Brønsted acid site. BET results revealed that the surface area and pore volume of the catalyst decreased after ZSM-5 was impregnated with zinc, while the pore size increased. When using the bifunctional catalyst, the pH value and heating value of upgraded camelina oils increased, while the oxygen content and moisture content decreased. Additionally, the yield rate of hydrocarbon fuels increased, while the density and oxygen content decreased. Because of a high content of fatty acids, the distillation residues of cracking oils might be recycled to the process to improve the hydrocarbon fuel yield rate.
The biochar source-processing combination provides a rich diversity of biochars to evaluate for s... more The biochar source-processing combination provides a rich diversity of biochars to evaluate for soil amendment use and determines the persistence of biochar within the soil. The potential of biochar as a soil amendment is dependent on its physical and chemical properties. Biochar interacts with other soil components such as ions, organic matter, and clay. Biochar properties range from acidic to alkaline depending on source and manufacturing process. The challenge is to identify a biochar source and processing combination that will optimize its efficiency as a soil amendment and still allow utility of the biomass as a bioenergy production. Biochar application has been shown to improve soil physical, chemical, and biological properties. Application of biochar has been reported increase available water, build soil organic matter, enhance nutrient cycling, lower bulk density, act as a liming agent, and reduce transfer of pesticides and nutrients to surface and ground water. The benefits...
ABSTRACT In this study, modified clean fractionation process was optimized for prairie cordgrass,... more ABSTRACT In this study, modified clean fractionation process was optimized for prairie cordgrass, with usage of alternative organic constituent –ethyl acetate. Other constituents of the solvent mixture included ethanol and water. Clean fractionation solvent was used in different proportions of the constituents. Process efficiency was determined by lignin recovery, solvent composition, as well as time and temperature applied to each sequential process. Glucose yield during enzymatic hydrolysis and overall pretreatment were calculated. Optimal conditions (125℃, 37 min, with the solvent composition of ester:ethanol:water = 32.5:22.5:45) yielded a 20% lignin recovery, 38% glucose yield during enzymatic hydrolysis and 26% xylose recovery in aqueous fraction. Citation: Cybulska I, Lei H W, Julson J, Brudecki G. Optimization of modified clean fractionation of prairie cordgrass. Int J Agric & Biol Eng, 2012; 5(2): 42-51.
Non-edible sunflower oils that were extracted from sunflower residual wastes were catalytically c... more Non-edible sunflower oils that were extracted from sunflower residual wastes were catalytically cracked over a ZSM-5 catalyst in a fixed-bed reactor at three different reaction temperatures: 450°C, 500°C and 550°C. The catalyst was characterized using XRD, FT-IR, BET and SEM. Characterizations of the upgraded sunflower oils, hydrocarbon fuels, distillation residues and non-condensable gases were carried out. The effect of the reaction temperature on the yield and quality of liquid products was discussed. The results showed that the reaction temperature affected the hydrocarbon fuel yield but had a minor influence on its properties. The highest conversion efficiency from sunflower oils to hydrocarbon fuels was 30.1%, which was obtained at 550°C. The reaction temperature affected the component content of the non-condensable gases. The non-condensable gases generated at 550°C contained the highest content of light hydrocarbons (C1C5), CO, CO2 and H2. Compared to raw sunflower oils, the...
The tentative connection between the biochar surface chemical properties and their influence on m... more The tentative connection between the biochar surface chemical properties and their influence on microbially mediated mineralization of C, N, and S with the help of enzymes is not well established. This study was designed to investigate the effect of different biomass conversion processes (microwave pyrolysis, carbon optimized gasification, and fast pyrolysis using electricity) on the composition and surface chemistry of biochar materials produced from corn stover (Zea mays L.), switchgrass (Panicum virgatum L.), and Ponderosa pine wood residue (Pinus ponderosa Lawson and C. Lawson) and determine the effect of biochars on mineralization of C, N, and S and associated soil enzymatic activities including esterase (fluorescein diacetate hydrolase, FDA), dehydrogenase (DHA), β-glucosidase (GLU), protease (PROT), and aryl sulfatase (ARSUL) in two different soils collected from footslope (Brookings) and crest (Maddock) positions of a landscape. Chemical properties of biochar materials produced from different batches of gasification process were fairly consistent. Biochar materials were found to be highly hydrophobic (low H/C values) with high aromaticity, irrespective of biomass feedstock and pyrolytic process. The short term incubation study showed that biochar had negative effects on microbial activity (FDA and DHA) and some enzymes including β-glucosidase and protease.
2013 Kansas City, Missouri, July 21 - July 24, 2013, 2013
ABSTRACT Biomass is known as the only source for production of renewable liquid transportation bi... more ABSTRACT 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.
2013 Kansas City, Missouri, July 21 - July 24, 2013, 2013
ABSTRACT Biofuel is an alternative to fossil fuels with benefits of less impact on environment, n... more ABSTRACT 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.
2012 Dallas, Texas, July 29 - August 1, 2012, 2012
ABSTRACT Catalysts play critical roles in hydrotreating and hydrocracking processes of upgrading ... more ABSTRACT Catalysts play critical roles in hydrotreating and hydrocracking processes of upgrading biomass-derived bio-oil to drop-in fuels. The selectivity and deactivate of catalysts, however, still remain biggest challenge. By using ZSM-5, aluminum, and activated carbon as supports, different catalysts made up with Ru were prepared and tested in a bio-oil upgrading process. The catalysts’ performances were investigated and compared in term of surface properties. The results showed that the ZSM-5 based catalysts got more water phase because of its highest surface acidity. The alumina changed to aluminum hydroxide in the presence of water at the reaction conditions. Activated carbon based catalysts showed good catalytic performance with more hydrocarbons and less water phase content in the upgraded bio-oil. All of upgraded bio-oils were verified by chemical analysis using a GC-MS. Nonetheless, further study for the kinetics of catalytically upgrading bio-oil is recommended.
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Papers by James Julson