TY - JOUR
T1 - Characterization of biocrudes recovered with and without solvent after hydrothermal liquefaction of algae
AU - Xu, Donghai
AU - Savage, Phillip E.
N1 - Funding Information:
We gratefully acknowledge the financial support from the University of Michigan College of Engineering , the National Science Foundation ( EFRI-0937992 ), the National Natural Science Foundation of China (no. 21206132 ), the Specialized Research Fund for the Doctoral Program of Higher Education (no. 20120201120069 ), the Fundamental Research Funds for the Central Universities (no. xjj2012032 ), the National Science Foundation for Post-doctoral Scientists of China (no. 2013 M540748 ), and the State Scholarship Fund for University Key Teachers from the Ministry of Education of China to Study Abroad as a Visiting Scholar (grant no. 201206285008 ).
Publisher Copyright:
© 2014 Elsevier B.V.
PY - 2014/10/1
Y1 - 2014/10/1
N2 - Bench-scale, batch experiments exploring algae hydrothermal liquefaction typically use organic solvents such as dichloromethane (DCM) to recover biocrude from the reactor contents. Commercial-scale, continuous processes, however, may separate biocrude and the aqueous phase co-product without solvent use. Herein, we provide the first thorough examination of the influence of DCM extraction on biocrude yield and composition from microalgae liquefaction in hot compressed water (350. °C, 20. min). We provide gravimetric biocrude yields and biocrude characterization via elemental analysis, GC-MS, NMR, and IR spectroscopies. The application of DCM increases the biocrude yield because it extracts water-soluble compounds from the aqueous phase co-product. Indeed, the biocrude recovered from the aqueous phase accounted for about 8. wt% of the total amount of biocrude. The addition of these molecules diminishes the biocrude quality, however, by decreasing the C and H content, increasing the O and N content, and thereby decreasing the higher heating value of the biocrude. The biocrude extracted from the aqueous phase had a remarkably different elemental composition than did the biocrude recovered without solvent. The O and N contents were more than twice as high, and the higher heating value was 20% lower. The biocrudes recovered directly from hydrothermal liquefaction (e.g., without water and DCM coming into contact) were 87%-88% C and H, and possessed a higher heating value of >. 39. MJ/kg.
AB - Bench-scale, batch experiments exploring algae hydrothermal liquefaction typically use organic solvents such as dichloromethane (DCM) to recover biocrude from the reactor contents. Commercial-scale, continuous processes, however, may separate biocrude and the aqueous phase co-product without solvent use. Herein, we provide the first thorough examination of the influence of DCM extraction on biocrude yield and composition from microalgae liquefaction in hot compressed water (350. °C, 20. min). We provide gravimetric biocrude yields and biocrude characterization via elemental analysis, GC-MS, NMR, and IR spectroscopies. The application of DCM increases the biocrude yield because it extracts water-soluble compounds from the aqueous phase co-product. Indeed, the biocrude recovered from the aqueous phase accounted for about 8. wt% of the total amount of biocrude. The addition of these molecules diminishes the biocrude quality, however, by decreasing the C and H content, increasing the O and N content, and thereby decreasing the higher heating value of the biocrude. The biocrude extracted from the aqueous phase had a remarkably different elemental composition than did the biocrude recovered without solvent. The O and N contents were more than twice as high, and the higher heating value was 20% lower. The biocrudes recovered directly from hydrothermal liquefaction (e.g., without water and DCM coming into contact) were 87%-88% C and H, and possessed a higher heating value of >. 39. MJ/kg.
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U2 - 10.1016/j.algal.2014.08.007
DO - 10.1016/j.algal.2014.08.007
M3 - Article
AN - SCOPUS:84908360946
SN - 2211-9264
VL - 6
SP - 1
EP - 7
JO - Algal Research
JF - Algal Research
IS - PA
ER -