Zuogang Guo

Properties of Bio-oil from Fast Pyrolysis of Rice Husk

Abstract Physicochemical properties of bio-oil obtained from fast pyrolysis of rice husk were studied in the present work. Molecular distillation was used to separate the crude bio-oil into three fractions viz . light fraction, middle fraction and heavy fraction. Their chemical composition was analyzed by gas chromatograph and mass spectrometer (GC-MS). The thermal behavior, including evaporation and decomposition, was investigated using thermogravimetric analyzer coupled with Fourier transform infrared spectrometer (TG-FTIR). The product distribution was significantly affected by contents of cellulose, hemicellulose and lignin. The bio-oil yield was 46.36% (by mass) and the yield of gaseous products was 27% (by mass). The chemicals in the bio-oil included acids, aldehydes, ketones, alcohols, phenols, sugars, etc . The light fraction was mainly composed of acids and compounds with lower boiling point temperature, the middle and heavy fractions were consisted of phenols and levoglucosan. The thermal stability of the bio-oil was determined by the interactions and intersolubility of compounds. It was found that the thermal stability of bio-oil was better than the light fraction, but worse than the middle and heavy fractions.

Separation of acid compounds for refining biomass pyrolysis oil

Abstract The large-scale utilization of biomass pyrolysis oil directly as high-grade energy resources has been quite limited due to its high water content and acidity. The water and acid compounds as a whole were separated from the pyrolysis oil by molecular distillation. One fraction obtained is rich in acid compounds, and the others are refined bio-oil I (heavy distillate fractions) and II (room temperature condensate), which have lower water content, weaker acidity, and higher heating value. The physical properties of the crude and refined bio-oil, such as the PH value, heating value, and water content were studied. The results indicated that water and acid compounds are separated effectively from the crude bio-oil. The content of carboxylic acids in crude bio-oil is about 18.85%, whereas that in the refined bio-oil I and II is decreased to 0.96% and 2.2%, respectively.

Review of Bio-oil Upgrading Technologies and Experimental Study on Emulsification of Bio-oil and Diesel

Pyrolysis oil (also called bio-oils) produced from biomass is a promising substitute for fossil fuels. However, bio-oil has many shortcomings, such as high viscosity, high oxygenate content, low stability and low heating value. Therefore, it is hard for direct high-grade fuel utilization before upgrading. In this paper, bio-oil upgrading techniques, such as catalytic hydrogenation, catalytic cracking, catalytic steam reforming, catalytic esterification and emulsification, were first reviewed. Then, emulsification experiment between whole components bio-oil and 0# diesel was carried out. Bio-oil was obtained from Shabili timber on a fluidized fast pyrolysis reactor. Span and Tween series surfactants were used as emulsifiers. It was found that the optimal value of hydrophile and lipophile balance (HLB) value for bio-oil and diesel emulsification was approximate 6.

Experimental Research on Catalytic Esterification of Bio-Oil Volatile Fraction

Carboxylic acids were attributed to the corrosivity of bio-oil and catalytic esterification was carried out to convert carboxylic acids and reduce the bio-oil corrosivity. After upgrading by esterification with propanol on a developed catalyst, the upgraded bio-oil had a higher heating value and lower carboxylic acids content. The carboxylic acids content in the Volatile fraction of Bio-Oil (VBO) was 28.81%, while that in the Upgraded Bio-Oil (UBO) declined to 2.43%. A carboxylic acids conversion of 91.57% was achieved though there was 71.42 wt% water content in VBO. It meant that this modified catalyst had a high catalytic activity and it was also hydrothermal resistant. To demonstrate the superior catalytic activity of the modified catalyst, BET, FT-IR and XRD were performed for catalysts characterization.

Production of Bio-gasoline by Co-cracking of Acetic Acid in Bio-oil and Ethanol

Abstract Acetic acid was selected as the model compound representing the carboxylic acids present in bio-oil. This work focuses the co-cracking of acetic acid with ethanol for bio-gasoline production. The influences of reaction temperature and pressure on the conversion of reactants as well as the selectivity and composition of the crude gasoline phase were investigated. It was found that increasing reaction temperature benefited the conversion of reactants and pressurized cracking produced a higher crude gasoline yield. At 400 °C and 1 MPa, the conversion of the reactants reached over 99% and the selectivity of the gasoline phase reached 42.79% (by mass). The gasoline phase shows outstanding quality, with a hydrocarbon content of 100%.

Catalytic Esterification of Model Compounds of Biomass Pyrolysis Oil

Biomass pyrolysis oil is a complex mixture containing a wide variety of oxygenated compounds, which results in difficulties in bio-oil upgrading. To gain a clearer understanding of the reaction pathways, seven compounds were chosen to represent biomass pyrolysis oil. In this paper, catalytic desertification was applied to convert the carboxylic acids into esters. The influences of reaction time and water content were studied, and a conversion rate about 80% of carboxylic acids was reached

Catalytic Cracking of Ketone Components in Biomass Pyrolysis Oil

The experimental research on catalytic cracking of ketone components in biomass pyrolysis oil was carried out on a fix-bed reactor, using HZSM-5 zeolite as the catalyst. Based on the results, coke formation was little during the cracking of ketone components, and the main cracking products were aromatic hydrocarbons and unsaturated alicyclic hydrocarbons. Meanwhile, hydrocarbons were easily produced at higher volume hour space velocity (VHSV). The selectivity of hydrocarbons was almost 100% when the VHSV was 3 h -1 . While it decreased to 64.79% when the VHSV was 1 h -1 . When the reaction temperature was 400°C, not only high ketone components conversion was reached, but also high selectivity of hydrocarbons was achieved.