Hydrothermal liquefaction of low-lipid microalgae Tetraselmis chuii: Effect of temperature and reaction time

2021 ◽  
Author(s):  
Samuel Andar Haryanto ◽  
Yano Surya Pradana
RSC Advances ◽  
2017 ◽  
Vol 7 (15) ◽  
pp. 8944-8951 ◽  
Author(s):  
Bo Zhang ◽  
Qisong Lin ◽  
Qinhui Zhang ◽  
Kejing Wu ◽  
Weihua Pu ◽  
...  

In this paper, Euglena sp. microalgae with low lipid and high ash contents were successfully converted into bio-oil with/without catalysts through hydrothermal liquefaction (HTL) at 280 °C and a reaction time of 30 min.


2009 ◽  
Vol 6 (2) ◽  
pp. 399-411 ◽  
Author(s):  
G. S. Jha ◽  
P. Chhabra ◽  
G. Suri ◽  
M. Tyagi ◽  
P. Arora ◽  
...  

Sulfur and chlorine containing bifunctional diols with C-S bond has been prepared starting from chloroepoxy alkane and thioalcohol. The studies of FTIR, TLC, HPLC and NMR have been used to understand the reaction mechanism, as well as for optimization of the reaction parameters. The reaction is highly exothermic and the effect of temperature, rate of addition of reagents and reaction time are important factors affecting the formation of diol. Viscosity studies, HPLC, FTIR, NMR and acid number studies have shown that, these parameters could be used as process control parameters for the synthesis of diol. Refractive index of the synthesized diol is found to be higher than that of the reactants used.


2019 ◽  
Vol 26 (2) ◽  
pp. 185-191
Author(s):  
Gamal Mohamed Attia MAHRAN ◽  
Abdel-Nasser Mohamed OMRAN ◽  
El-Sayed Sedek ABU SEIF

A modified Al-Si alloy containing up to 15 wt.% Si has been obtained from the reaction of sodium fluosilicate (Na2SiF6) with molten aluminum. This work attempted to estimate the mechanism of the reaction of Na2SiF6 with molten aluminum to produce Al-Si alloys. The effect of temperature, Na2SiF6/Al Wt ratio and reaction time on the formation of Al-Si alloy were investigated. The thermodynamic data, kinetic and rate of the reaction were studied. The results showed the possibility of the reaction between Na2SiF6 and molten aluminum thermodynamically, and that this reaction might be controlled chemically. The current study aims to optimize the factors that affecting the preparation of a modified Al-Si alloy from a reduction of sodium fluosilicate using molten aluminium. Temperature 950 oC, reaction time 20 – 25 min and Na2SiF6/Al Wt ratio related to the applied Si percentage. The prepared alloys could be modified due to the presence of Na2SiF6 in the used material as a source of sodium in response to modifying the produced Al-Si alloys. The microstructure by using LOM, SEM, and EDX proved that the needle-like silicon converts to fine fibrous. The volume fraction of primary Si reduces and the eutectic point moves to a higher silicon concentration. The modification improves the wear characteristics and increases the tensile and hardness.


2019 ◽  
Author(s):  
M. Syukri ◽  
N. R. Purba ◽  
B. R. Hutajulu ◽  
D. Alfizah ◽  
A. Hutagalung ◽  
...  

2019 ◽  
Vol 15 (1) ◽  
pp. 186-198
Author(s):  
Gopalakrishnan Govindasamy ◽  
Rohit Sharma ◽  
Sunu Subramanian

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


Author(s):  
Muhammad Salman Haider ◽  
Daniele Castello ◽  
Karol Michal Michalski ◽  
Thomas Helmer Pedersen ◽  
Lasse Rosendahl

To obtain drop-in fuel properties from non-feed biomass, we herein report the catalytic hydrotreatment of microalgae biocrude, produced from hydrothermal liquefaction (HTL) of Spirulina. Our contribution focuses on the effect of temperature, initial H2 pressure, and residence time on the removal of heteroatoms (O and N). In contrast to common hydrotreating experimental protocols at batch scale, we devised a set of two-level factorial experiments and studied the most influential parameters affecting the removal of heteroatoms. It was found that up to 350 °C, the degree of deoxygenation (de-O) is mainly driven by temperature, whereas the degree of denitrogenation (de-N) also relies on initial H2 pressure and temperature-pressure interaction.Based on this, complete deoxygenation was obtained at mild operating conditions (350 °C), reaching a concurrent 47 % denitrogenation. Moreover, three optimized experiments are reported with 100 % removal of oxygen. In addition, the analysis by GC-MS and Sim-Dis gives insight to the fuel quality. The distribution of heteroatom N in lower (<340 °C) and higher (>340 °C) fractional cuts is studied by a fractional distillation unit following ASTM D-1160. Final results show that 63-68 % of nitrogen is concentrated in higher fractional cuts.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Blessing E Eboibi

Producing biocrude from hydrothermal liquefaction (HTL) of microalgae has the potential to complement fossil fuels, while simultaneously reducing greenhouse gas emissions. However, biocrude recovery from the HTL reaction product has been a concern. In this study, analysis of yields and property of biocrude recovered with and without using dichloromethane (DCM) organic solvent was investigated. The HTL experiment were performed at reaction temperature of 350oC and 20 min reaction time using 16 w/w % solids each of Spirulina sp. and Tetraselmis sp. Data obtained showed that use of DCM favours maximum biocrude yield but of lower quality when compared with DCM-free biocrude. Biocrude yield of 58wt% was obtained from Tetraselmis sp. and 48wt% from Spirulina sp. when DCM was used. About 38 and 40wt% biocrude yields were derived with DCM-free recovery process. Higher carbon content, energy dense, and lower heteroatoms content constitutes biocrude recovered without DCM treatment, which is in contrast to the biocrude recovered with DCM. In addition, an average energy input of 13MJ/kg is required to produce unit biocrude, with an additional energy input ~0.5MJ/kg to evaporate DCM when used in biocrude recovery.Keywords— Bio-energy, Hydrothermal liquefaction, Microalgae, Organic solvent, Separation method


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