Separation of chemical groups from bio-oil water-extract via sequential organic solvent extraction

Abstract

The chemical complexity of bio-oil aqueous phase limits its efficient utilization. To improve the efficiency of the bio-oil biorefinery, this study focused on the separation of chemical groups from the bio-oil water-extract via sequential organic solvent extractions. Due to their high recoverability and low solubility in water, four solvents (hexane, petroleum ether, chloroform, and ethyl acetate) with different polarities were evaluated, and the optimum process conditions for chemical extraction were determined. Chloroform had high extraction efficiency for furans, phenolics, and ketones. In addition to these classes of chemical, ethyl acetate had a high extraction efficiency for organic acids. The sequential extraction using chloroform followed by ethyl acetate resulted in 62.2 wt.% of original furans, ketones, alcohols, and phenolics being extracted into chloroform, while 62 wt.% acetic acid was extracted into ethyl acetate, leaving behind a high concentration of levoglucosan (~53.0 wt.%) in the final aqueous phase. Chemicals separated via the sequential extraction could be used as feedstocks in a biorefinery using processes such as catalytic upgrading of furans and phenolics to hydrocarbons, fermentation of levoglucosan to produce alcohols and diols, and hydrogen production from organic acids via microbial electrolysis.

Characterization of Fast Pyrolysis Bio-Oil from Hardwood and Softwood Lignin

“…The lignin obtained by Kraft process contains considerable amounts of sulfur compounds including lignosulfates, which is considered as one of the disadvantages of the Kraft process [34]. As stated in the literature, the oxygen content of bio-oil varies in the range of 35-40% [35]. The lowest amount of oxygen was found for Sigma Kraft Lignin (22.91%).…”

“…As can be seen from Table 3, phenolic and aromatic compounds were separated by toluene fraction. Phenolic compounds have lower polarity than acids and furans and according to the functional group and previously reported studies phenolic family was considered the components, which include 1, 2-benzenediol, phenol, 3-ethylphenol, 2, 6-dimethoxyphenol [35]. The toluene fraction analysis of sigma Kraft Lignin shows the separation of different phenolic components such as phenol, phenol, 2-methoxy, and 2-methoxy-6-methylphenol, guaiacol and 1, 2-benzenediol.…”

Catalizadores bifuncionales a base de imogolita, Ni y Mo para el mejoramiento de las propiedades fisicoquímicas del bio-aceite proveniente de cáscara de avena

“…La composición química del bio-aceite fue obtenida mediante el fraccionamiento químico con solventes orgánicos de la fracción acuosa, debido al alto contenido en agua de los bio-aceites. El procedimiento se resume en la Figura 1 y se basó en la metodología propuesta por [16]. Las fracciones obtenidas fueron llevadas a rotavapor y luego fueron analizadas mediante cromatografía gaseosa con detector de masas (Shimadzu) equipado con una columna capilar RTx-5ms.…”

Efficient Conversion of Aqueous-Waste-Carbon Compounds Into Electrons, Hydrogen, and Chemicals via Separations and Microbial Electrocatalysis

“…Some investigators studied the separation of various chemical groups with organic solvents. Ren et al (2017) separated FIGURE 1 | Separation scheme integrating physical, chemical, and electro-separations to fractionate bio-oil for production of hydrogen, fuels and chemicals. Figure reprinted with permission from .…”

“…Furanic and phenolic compounds, generated from the degradation of sugar and lignin polymers during thermal or thermochemical pretreatment of lignocellulosic biomass for biofuel production, are widely found in the BOAP (Jones et al, 2009;Ren et al, 2017). Furanic and phenolic compounds contribute to the instability and corrosiveness of the bio-oil, as well as the BOAP (Jones et al, 2013).…”