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.
Butanol can be produced from biomass via fermentation and used in vehicles. Unfortunately, butano... more Butanol can be produced from biomass via fermentation and used in vehicles. Unfortunately, butanol is toxic to the microbes, and this can slow fermentation rates and reduce butanol yields. Butanol can be efficiently removed from fermentation broth by gas stripping, thereby preventing its inhibitory effects. Original active carbon (AC) and AC samples modified by nitric acid hydrothermal modification were assessed for their ability to adsorb butanol vapor. The specific surface area and oxygen-containing functional groups of AC were tested before and after modification. The adsorption capacity of unmodified AC samples was the highest. Hydrothermal oxidation of AC with HNO3 increased the surface oxygen content, Brunauer-Emmett-Teller (BET) surface area, micropore, mesopore and total pore volume of AC. Although the pore structure and specific surface area were greatly improved after hydrothermal oxidization with 4M HNO3, the increased oxygen on the surface of AC decreased the dynamic ads...
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.
Butanol can be produced from biomass via fermentation and used in vehicles. Unfortunately, butano... more Butanol can be produced from biomass via fermentation and used in vehicles. Unfortunately, butanol is toxic to the microbes, and this can slow fermentation rates and reduce butanol yields. Butanol can be efficiently removed from fermentation broth by gas stripping, thereby preventing its inhibitory effects. Original active carbon (AC) and AC samples modified by nitric acid hydrothermal modification were assessed for their ability to adsorb butanol vapor. The specific surface area and oxygen-containing functional groups of AC were tested before and after modification. The adsorption capacity of unmodified AC samples was the highest. Hydrothermal oxidation of AC with HNO3 increased the surface oxygen content, Brunauer-Emmett-Teller (BET) surface area, micropore, mesopore and total pore volume of AC. Although the pore structure and specific surface area were greatly improved after hydrothermal oxidization with 4M HNO3, the increased oxygen on the surface of AC decreased the dynamic ads...
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