Bio-oil production by pyrolysis of Azolla filiculoides and Ulva fasciata macroalgae
نویسندگان
1 Department of Chemistry and Chemical Engineering, Rasht Branch, Islamic Azad University, Rasht, Iran
2 Biofuel Research Laboratory, Caspian Faculty of Engineering, College of Engineering, University of Tehran, Rezvanshar, Guilan, Iran
3 Department of Chemistry and Chemical Engineering, Rasht Branch, Islamic Azad University, Rasht, Iran
4 Biofuel Research Laboratory, Caspian Faculty of Engineering, College of Engineering, University of Tehran, Rezvanshar, Guilan, Iran
doi
10.22034/GJESM.2021.03.02چکیده
BACKGROUND AND OBJECTIVES: In this study, the characteristics of bio-oil samples produced through slow pyrolysis of two different macroalgae, i.e. Azolla filiculoides and Ulva fasciata, at optimized conditions were determined and compared.METHODS: For this purpose, the effects of temperature (300-500 °C), carrier gas flow rate (0.2-0.8 L/min), and heating rate (10-20 °C/min) on the final bio-oil production were optimized using response surface methodology established by a central composite design.FINDINGS: The highest bio-oil yield from U. fasciata (34.29%) was obtained at the temperature of 500 °C, nitrogen flow rate of 0.2 L/min, and heating rate of 10 °C/min. As for A. filiculoides feedstock, the highest bio-oil yield (30.83%) was achieved at the temperature of 461 °C, nitrogen flow rate of 0.5 L/min, and heating rate of 20 °C/min. Both bio-oil samples contained saturated and unsaturated hydrocarbons. However, the average hydrocarbon chain length was relatively shorter in U. fasciata bio-oil (C4-C16) than in bio-oil from A. filiculoides (C6-C24). Although both bio-oils had almost identical heating values, the U. fasciata bio-oil showed more appropriate properties, i.e. lower viscosity and density. Furthermore, the energy recovery from U. fasciata pyrolysis was calculated as 56.6% which was almost 1.5 times higher than the energy recovery from A. filiculoides pyrolysis.CONCLUSION: The results indicated that U. fasciata bio-oil, with its superior characteristics, could be proposed as a promising candidate for application in diesel-based automotive industries.
