Hydrothermal Liquefaction of Biomass in Hot-Compressed Water, Alcohols, and Alcohol-Water Co-solvents for Biocrude Production

This study reviewed and summarized the literature regarding the use of alcohols during hydrothermal liquefaction (HTL) of algal biomass feedstocks. The use of both pure alcohols and alcohol-water co-solvents were considered. Based upon this review, laboratory experiments were conducted to investigate the impacts of different alcohol co-solvents (ethanol, isopropanol, ethylene glycol, and glycerol) on the HTL treatment of a specific saltwater microalga (Tetraselmis sp.) at two temperatures: 300 °C and 350 °C. Based on their performance, two co-solvents, isopropanol and ethylene glycol, were selected to explore the effects of varying solvent concentrations and reaction temperatures on product yields and biocrude properties. The type and amount of added alcohol did not significantly affect the biocrude yield or composition. Biocrude yields were in the range of 30–35%, while a nearly constant yield of 21% insoluble products was observed, largely resulting from ash constituents within the algal feedstock. The benefits of using alcohol co-solvents (especially isopropanol) were the reduced viscosity of the biocrude products and reduced rates of viscosity increase with biocrude aging. These effects were attributed mainly to the physical properties of the co-solvent mixtures (solubility, polarity, density, etc.) rather than chemical processes. Under the reaction conditions used, there was no evidence that the co-solvents participated in biocrude production by means of hydrogen donation or other chemical processes. Recovery and recycling of the co-solvent present various challenges, depending upon the type and amount of the co-solvent that is used. For example, glycol solvents are recovered nearly completely within the aqueous product stream, whereas simple alcohols are partitioned between the biocrude and aqueous product streams. In commercial applications, the slight benefits provided by the use of co-solvents must be balanced by the challenges of co-solvent recovery and recycling.

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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.

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Hydrothermal liquefaction of woody biomass in hot-compressed water: Catalyst screening and comprehensive characterization of bio-crude oils

Fuel ◽

10.1016/j.fuel.2015.08.055 ◽

2015 ◽

Vol 162 ◽

pp. 74-83 ◽

Cited By ~ 93

Author(s):

Laleh Nazari ◽

Zhongshun Yuan ◽

Sadra Souzanchi ◽

Madhumita B. Ray ◽

Chunbao (Charles) Xu

Keyword(s):

Woody Biomass ◽

Hydrothermal Liquefaction ◽

Crude Oils ◽

Catalyst Screening ◽

Hot Compressed Water ◽

Comprehensive Characterization

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Hydrothermal liquefaction of wheat straw in hot compressed water and subcritical water–alcohol mixtures

The Journal of Supercritical Fluids ◽

10.1016/j.supflu.2014.01.006 ◽

2014 ◽

Vol 93 ◽

pp. 121-129 ◽

Cited By ~ 44

Author(s):

Pratap T. Patil ◽

Udo Armbruster ◽

Andreas Martin

Keyword(s):

Wheat Straw ◽

Subcritical Water ◽

Hydrothermal Liquefaction ◽

Alcohol Mixtures ◽

Hot Compressed Water ◽

Water Alcohol

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Renewable Diesel Blendstocks and Biopriviliged Chemicals Distilled from Algal Biocrude Oil Converted via Hydrothermal Liquefaction

10.26434/chemrxiv.9630695 ◽

2019 ◽

Author(s):

Wan-Ting (Grace) Chen ◽

Zhenwei Wu ◽

Buchun Si ◽

Yuanhui Zhang

Keyword(s):

Oxidation Stability ◽

Ash Content ◽

Hydrothermal Liquefaction ◽

Fractional Distillation ◽

Chemical Compositions ◽

Steam Temperature ◽

Renewable Diesel ◽

Commodity Chemicals ◽

Biocrude Oil ◽

Specification Analysis

This study aims to produce renewable diesel and biopriviliged chemicals from microalgae that can thrive in wastewater environment. <i>Spirulina</i> (SP) was converted into biocrude oil at 300ºC for a 30-minute reaction time via hydrothermal liquefaction (HTL). Next, fractional distillation was used to separate SP-derived biocrude oil into different distillates. It was found that 62% of the viscous SP-derived biocrude oil can be separated into liquids at about 270ºC (steam temperature of the distillation). Physicochemical characterizations, including density, viscosity, acidity, elemental compositions, higher heating values and chemical compositions, were carried out with the distillates separated from SP-derived biocrude oil. These analyses showed that 15% distillates could be used as renewable diesel because they have similar heating values (43-46 MJ/kg) and carbon numbers (ranging from C8 to C18) to petroleum diesel. The Van Krevelan diagram of the distillates suggests that deoxygenation was effectively achieved by fractional distillation. In addition, GC-MS analysis indicates that some distillates contain biopriviliged chemicals like aromatics, phenols and fatty nitriles that can be used as commodity chemicals. An algal biorefinery roadmap was proposed based on the analyses of different distillates from the SP-derived biocrude oil. Finally, the fuel specification analysis was conducted with the drop-in renewable diesel, which was prepared with 10 vol.% (HTL10) distillates and 90 vol.% petroleum diesel. According to the fuel specification analysis, HTL10 exhibited a qualified lubricity (<520 µm), acidity (<0.3 mg KOH/g) and oxidation stability (>6 hr), as well as a comparable net heat of combustion (1% lower), ash content (29% lower) and viscosity (17% lower) to those of petroleum diesel. Ultimately, it is expected that this study can provide insights for potential application of algal biocrude oil converted via HTL.

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Determination of δ-hexadecansultone in sodium α-olefinesulphonates and liquid detergents using gas chromatography-mass spectrometry (GC/MS)

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2019-85-7-16-21 ◽

2019 ◽

Vol 85 (7) ◽

pp. 16-21

Author(s):

Liliya R. Mubarakova ◽

German K. Budnikov

Keyword(s):

Multicomponent Mixture ◽

Operating Mode ◽

Complete Separation ◽

Gas Chromatography Mass Spectrometry ◽

Liquid Detergent ◽

Cyclic Esters ◽

Alcohol Water ◽

Household Chemicals ◽

Hydrolysis Of

Sultones are cyclic esters of hydroxysulfonic acids, which are formed in the process of sulfonation of α-olefins with sulfur trioxide gas. More stable sultones may be present in the final product — an anionic surfactant — sodium α-olefin sulfonate (AOC-Na). AOC-Na is widely used in the production of household chemicals and cosmetic products, including liquid dishwashing detergents. Sultones are strong skin sensitizers, their level in AOC-Na should be strictly controlled and not exceed 5 ppm. Operational and strict control of the sultone content upon AOC-Na production allows timely adjustment at the stage of hydrolysis, which leads to a more complete disclosure of the sultone cycle with the formation of the corresponding olefin sulfonates and hydroxyalkanesulfonates. We propose a method for determining δ-hexadecansultone in liquid dishwashing detergents and sodium α-olefinsulfonates obtained on the basis of α-olefins of C14 – C16 fractions using GC/MS, which provides shortening of sample preparation and keeps the sensitivity with a detection limit of 0.02 mg/kg. The effect of various weakly polar and non-polar organic solvents used for Sultone extraction from AOC-Na and liquid detergent on liquid extraction based on the dispersion of the extractant in an alcohol/water phase is studied. When selecting the solvent we have shown that the use of diethyl ether provided the best extraction of the analyte. Determination of the analyte extraction recovery was performed using the reaction of hydrolysis of the extracted mixture. We specified the operating mode of the device which provided complete separation of the components of the analyzed compounds including the samples of liquid detergent for dishes being a multicomponent mixture of complex composition.

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