Abstract
Liquefaction of biomass delivers a liquid bio-oil with relevant chemical and energetic applications. In this study we coupled it with short rotation coppice (SRC) intensively managed poplar cultivations aimed at biomass production while safeguarding environmental principles of soil quality and biodiversity. We carried out acid-catalyzed liquefaction, at 160 °C and atmospheric pressure, with eight poplar clones from SRC cultivations. The bio-oil yields were high, ranging between 70.7 and 81.5%. Average gains of bio-oil, by comparison of raw biomasses, in elementary carbon and hydrogen and high heating, were 25.6, 67, and 74%, respectively. Loss of oxygen and O/C ratios averaged 38 and 51%, respectively. Amounts of elementary carbon, oxygen, and hydrogen in bio-oil were 65, 26, and 8.7%, and HHV averaged 30.5 MJkg−1. Correlation analysis showed the interrelation between elementary carbon with HHV in bio-oil or with oxygen loss. Overall, from 55 correlations, 21 significant and high correlations among a set of 11 variables were found. Among the most relevant ones, the percentage of elementary carbon presented five significant correlations with the percentage of O (−0.980), percentage of C gain (0.902), percentage of O loss (0.973), HHV gain (0.917), and O/C loss (0.943). The amount of carbon is directly correlated with the amount of oxygen, conversely, the decrease in oxygen content increases the elementary carbon and hydrogen concentration, which leads to an improvement in HHV. HHV gain showed a strong positive dependence on the percentage of C (0.917) and percentage of C gain (0.943), while the elementary oxygen (−0.885) and its percentage of O loss (0.978) adversely affect the HHV gain. Consequently, the O/C loss (0.970) increases the HHV positively. van Krevelen’s analysis indicated that bio-oils are chemically compatible with liquid fossil fuels. FTIR-ATR evidenced the presence of derivatives of depolymerization of lignin and cellulose in raw biomasses in bio-oil. TGA/DTG confirmed the bio-oil burning aptitude by the high average 53% mass loss of volatiles associated with lowered peaking decomposition temperatures by 100 °C than raw biomasses. Overall, this research shows the potential of bio-oil from liquefaction of SRC biomasses for the contribution of renewable energy and chemical deliverables, and thereby, to a greener global economy.
Highlights
As society and scientific knowledge develop, it becomes increasingly important to reduce the dependency on petrochemicals due to their dwindling reserves and their negative impact on the environment inflicted by their exploration
In the fourth stage, corresponding to temperatures higher than 525 ◦ C, a slight mass loss of 6% was attributed to heavy compounds resulting from the condensation of liquefaction products that led to insoluble solids
This study evaluated the aptitude of bio-oils obtained via acid-catalyzed liquefaction of poplar woody biomasses from eight clones from short rotation crops
Summary
As society and scientific knowledge develop, it becomes increasingly important to reduce the dependency on petrochemicals due to their dwindling reserves and their negative impact on the environment inflicted by their exploration. Thermochemical liquefaction of different biomass feedstocks has been studied, including spruce [28], pinewood [22,29,30], eucalyptus [31,32,33], potato peels [34], cork powder [35], spent coffee beans [36], beech [37], or wheat straw [28,38,39] The results from such studies demonstrated that different biomasses, with distinct chemical compositions and structures, can be used for the acid-catalyzed liquefaction to produce bio-oils in high yields. To the best of our knowledge, the comparison between liquified biomasses from different poplar clones was never disclosed Within this context, our work supports further development on thermochemical conversion technologies to value this type of biomass feedstock
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
