Effect of hydration-calcination CaO on the deoxygenation of bio-oil from pyrolysis of Nannochloropsis sp.

ABSTRACT

To improve the quality of bio-oil, hydration-calcination CaO (HC CaO) was used to deoxygenate pyrolysis bio-oil from Nannochloropsis sp. As an economically and environmentally promising microalgae biorefinery process, this method produces valuable straight-chain alkanes, which are the main components of diesel. The results indicated that HC CaO significantly deoxygenated the bio-oil, improving its performance through the direct fixation of “active quasi-CO₂ intermediates”. When the HC CaO content was 25%, the low calorific value of the bio-oil reached its maximum value (39.350 kJ·g⁻¹), while the moisture content and kinematic viscosity of the bio-oil decreased to 2.102% and 4.458 mm²·s^−1, respectively. In particular, the oxygen content was reduced by 86.41%, and the O/C ratio notably decreased after adding HC CaO. Therefore, HC CaO offers a good alternative for preparing high-quality diesel substitutes, which would be broadly applied as a beneficial additive to bio-oil.

KEYWORDS:

• Nannochloropsis sp
• pyrolysis
• deoxygenation
• HC CaO
• bio-oil

Acknowledgments

This research has been funded by grants from the Key R & D major projects of the Ningxia Hui Autonomous Region (2018BCE01002), the Special Fund of Marine Renewable Energy (GHME2001SW02), the Key Project of the Natural Science Foundation of Shandong Province (ZR 2015QZ02) and the Qingdao Application Foundation Research Project (14-2-4-5-jch).

Additional information

Funding

This work was supported by the The Key project of Natural Science Foundation of Shandong Province [ZR 2015QZ02];Key R & D major projects of the Ningxia Hui Autonomous Region [2018BCE01002];The Special Fund of Marine Renewable Energy [GHME2001SW02];The Qingdao Application Foundation Research Project [14-2-4-5-jch].