Process Water Recycle in Hydrothermal Liquefaction of Microalgae To Enhance Bio-oil Yield

Kitchen waste (KW) has gradually become a prominent problem in municipal solid waste treatment. Hydrothermal liquefaction (HTL) is a promising method used to make fuel oil from food and KW. However, the upgrading of bio-oil is particularly important for the sake of industrial reuse. In this study, the KW from university restaurants was subjected to HTL experiments in order to study theoretical feasibility. With the change of conversion temperature and residence time, the optimal conversion working conditions in this study were determined according to the quality and yield of the bio-oil. Moreover, the bio-oil upgrading effects of different additives (hydrogen chloride, sodium hydroxide, and iron(III) chloride) on the HTL of KW were studied. Alkaline additives have an inhibitory effect on the bio-oil yield and positive effect on coke yield. Acidic additives and iron (Fe)-containing additives can promote bio-oil yield. As an important aspect of upgrading, the effect on the nitrogen content of bio-oil with additives was revealed. The alkaline and Fe-containing additives have little effect on reducing the viscosity of the bio-oil while with the appropriate ratio (2.5 mol•kg−1) of acidic additives to the raw material, the static and dynamic fluidity of the oil phase products are reduced to about 0.1 Pa•s.

Download Full-text

A review on process conditions for optimum bio-oil yield in hydrothermal liquefaction of biomass

Renewable and Sustainable Energy Reviews ◽

10.1016/j.rser.2010.11.054 ◽

2011 ◽

Vol 15 (3) ◽

pp. 1615-1624 ◽

Cited By ~ 533

Author(s):

Javaid Akhtar ◽

Nor Aishah Saidina Amin

Keyword(s):

Hydrothermal Liquefaction ◽

Oil Yield ◽

Process Conditions ◽

Bio Oil

Download Full-text

Effect of Composition of Iron-Cobalt Oxide Catalyst and Process Parameters on The Hydrothermal Liquefaction of Sugarcane Bagasse

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.15.1.5385.186-198 ◽

2019 ◽

Vol 15 (1) ◽

pp. 186-198

Author(s):

Gopalakrishnan Govindasamy ◽

Rohit Sharma ◽

Sunu Subramanian

Keyword(s):

Reaction Time ◽

Oxygen Content ◽

Sugarcane Bagasse ◽

Process Parameters ◽

Hydrothermal Liquefaction ◽

Oil Yield ◽

Iron Cobalt ◽

Bio Oil ◽

Biomass Ratio ◽

Total Oil

Development of catalyst with high deoxygenation activity and optimum process parameters are the key for getting the highest biooil yield with the least oxygen content by hydrothermal liquefaction. With this view, iron-cobalt oxides of Co/Fe ratio 0.33, 1.09, 2.35, and 3.52 were prepared by co-precipitation method, and characterized by XRD, BET surface area, chemical composition by EDX method, and evaluated for hydrothermal liquefaction of sugarcane bagasse in a high-pressure batch reactor under subcritical conditions using CO as process gas to find the optimum Co/Fe ratio and process parameters. Optimum Co/Fe ratio was found to be 1.09 as it gave the highest bio-oil yield of 57.6% with the least oxygen content of 10.8%, attributed to the cobalt ferrite, the major phase present in it. The optimum temperature, initial CO pressure, water/biomass ratio, catalyst/biomass ratio and reaction time for the highest oil yield with the least oxygen content were found to be 250 °C, 45 bar, 28, 0.4, and 120 min, respectively. From the effect of reaction time, it was found that much of the hydrolysis of lignocellulose to water soluble oxygenates, its deoxygenation to bio-oil and its deoxygenation to low oxygen containing bio-oil took place in initial 15 min, 15 to 60 min, and from 30 to 120 min, respectively. Total oil yield (%) was lower by 21% and % oxygen in total oil was higher by 9.9% for spent catalyst compared to fresh catalyst indicating the erosion in the deoxygenation activity of catalyst and thus need for improving its hydrothermal stability. Copyright © 2020 BCREC Group. All rights reserved

Download Full-text

Catalytic Hydrothermal Liquefaction of Microalgae using Fe-MCM 41 Catalyst in Presence of Carbon Monoxide

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.21782 ◽

2019 ◽

Vol 31 (3) ◽

pp. 690-694

Author(s):

R. Sharma ◽

A.K. Tiwari ◽

A. Singh ◽

N. Sharma

Keyword(s):

Chlorella Pyrenoidosa ◽

Hydrothermal Liquefaction ◽

Oil Yield ◽

Process Pressure ◽

Bio Oil ◽

Lower Temperature ◽

Hot Compressed Water ◽

Generation Biofuel ◽

Nitrogen Contents ◽

Mcm 41

Among the various types of biomass, microalgae have a potential to become a significant energy source for the production of third generation biofuel. The hydrothermal liquefaction is the direct biomass-to-liquid conversion route carried out in the hot compressed water with or without the presence of a catalyst. In this study, the process pressure and temperature is reduced, but at a lower temperature, bio-oil yield is not high enough to make hydrothermal liquefaction an economical technique. Thus, Fe-MCM 41 catalyst was used to increase the bio-oil yield at low temperatures (250 ºC). This catalyst increased the total bio-oil yield from 42.7 to 61.28 % in hydrothermal liquefaction of Chlorella pyrenoidosa. The bio-oil yield (%) of oil 1, 2 & 3 were 24.72, 17.08 & 19.48, respectively obtained at 250 ºC by using catalyst. Moreover, use of catalyst also resulted in the decrease in oxygen and nitrogen contents of bio-oil and consequently increases in its heating value.

Download Full-text

Hydrothermal liquefaction of microalgae after different pre-treatments

Energy Exploration & Exploitation ◽

10.1177/0144598718777107 ◽

2018 ◽

Vol 36 (6) ◽

pp. 1546-1555 ◽

Cited By ~ 2

Author(s):

Mikhail S Vlaskin ◽

Anatoly V Grigorenko ◽

Nadezhda I Chernova ◽

Sophia V. Kiseleva

Keyword(s):

Constant Temperature ◽

Research Group ◽

Arthrospira Platensis ◽

Hydrothermal Liquefaction ◽

Point Of View ◽

Water Soluble ◽

Oil Yield ◽

Oil Fraction ◽

Bio Oil ◽

Liquefaction Process

Hydrothermal liquefaction of different microalgae samples ( Arthrospira platensis cultivated by our research group) – fresh (directly after harvesting), dried and frozen – have been performed. In hydrothermal liquefaction process, the samples were heated up to 300°C for 30 min and kept at a constant temperature for 60 min. Then dichloromethane was added to the samples to extract the oil fraction. The products obtained after aqueous and dichloromethane solutions evaporation are referred to as water soluble organics and bio-oil correspondingly. The experiments on hydrothermal liquefaction of microalgae pre-treated in different ways were conducted for three independent harvest samples. The average values of bio-oil yield in the experiments with fresh, dried and frozen microalgae were equal to 44.07%, 39.97% and 39.65%, respectively. The average yields of water soluble organics were equal to 19.34%, 29.00% and 21.43% respectively. In all the experiments, the highest yield of bio-oil was reached for fresh microalgae. From this point of view, direct hydrothermal liquefaction processing of fresh microalgae seems to be more preferable that further enhances the advantage of hydrothermal liquefaction in comparison with other biomass-to-biofuel conversion methods.

Download Full-text

Catalytic Hydrothermal Liquefaction of Penicillin Residue for the Production of Bio-Oil over Different Homogeneous/Heterogeneous Catalysts

Catalysts ◽

10.3390/catal11070849 ◽

2021 ◽

Vol 11 (7) ◽

pp. 849

Author(s):

Chen Hong ◽

Zhiqiang Wang ◽

Yanxiao Si ◽

Yi Xing ◽

Jian Yang ◽

...

Keyword(s):

Heterogeneous Catalysts ◽

Catalytic Performance ◽

Hydrothermal Liquefaction ◽

Oil Yield ◽

Obvious Effect ◽

Heating Value ◽

Bio Oil ◽

Cracking Reaction ◽

Secondary Cracking ◽

Antibiotic Fermentation

In this study, penicillin residue (PR) was used to prepare bio-oil by hydrothermal liquefaction. The effects of homogeneous (organic acid and alkaline catalysts) and heterogeneous catalysts (zeolite molecular sieve) on the yield and properties of bio-oil were investigated. The results show that there are significant differences in the catalytic performance of the catalysts. The effect of homogeneous catalysts on the bio-oil yield was not significant, which only increased from 26.09 (no catalysts) to 31.44 wt.% (Na2CO3, 8 wt.%). In contrast, heterogeneous catalysts had a more obvious effect, and the oil yield reached 36.44 wt.% after adding 5 wt.% MCM-48. Increasing the amount of catalyst enhanced the yield of bio-oil, but excessive amounts of catalyst led to a secondary cracking reaction, resulting in a reduction in bio-oil. Catalytic hydrothermal liquefaction reduced the contents of heteroatoms (oxygen, mainly), slightly increased the contents of C and H in the bio-oil and increased the higher heating value (HHV) and energy recovery (ER) of bio-oil. FTIR and GC-MS analyses showed that the addition of catalysts was beneficial in increasing hydrocarbons and oxygen-containing hydrocarbons in bio-oil and reducing the proportion of nitrogen-containing substances. Comprehensive analyses of the distribution of aromatic, nitrogen-containing and oxygen-containing components in bio-oil were also performed. This work is beneficial for further research on the preparation of bio-oil by hydrothermal liquefaction of antibiotic fermentation residue.

Download Full-text