Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (Euterpe Oleracea Mart) Seeds

Abstract

In this work, the dried seeds of Açaí (Euterpe oleracea Mart) were submitted to pyrolysis to produce Bio-Oil. The pyrolysis reaction was carried out in a 143 L reactor, operating in batch at 450 ºC and 1.0 atm. Bio-Oil distillation was performed on a laboratory-scale column according to the boiling temperature range of fossil fuels. The physicochemical characterization of the bio-oil and the distillate fractions (gasoline, kerosene and diesel) were performed by the AOCS, ASTM and ABNT/NBR methods in terms of acidity index, density, refractive index and kinematic viscosity. The qualitative analysis of Bio-Oil was performed by FT-IR spectroscopy. Experiments show that the yields of coke and bio-oil gas were 4. 39, 35.67 and 30.56 % (by weight), respectively. The density and viscosity of Bio-Oil were 1.0468 g/cm 3 and 68.34 mm²/s, respectively;. Bio-Oil's FT-IR has identified the presence of hydrocarbons, carboxylic acids, ketones and phenols.

Online Separation of Biomass Fast-Pyrolysis Liquids via Fractional Condensation

“…Although GC analysis of the fractions indicates that fraction 3 had a higher concentration of selected phenolics, fraction 2 had a higher percentage of proton resonance in the aromatic region, while fraction 3 had more resonance associated with alcohols, carbohydrates, and alkyl side chains. In the 13 C NMR, it is evident that carbonyl compounds are more abundant in fraction 3 than in fractions 1 and 2 (Figure 5). Fraction 4 was separated at a temperature of 35 °C and phase-separated between an aqueous phase with a significant yield of 8.7 wt % from biomass and a very small organic fraction yielding 0.5 wt % from biomass containing a high concentration of phenols as shown by GC and NMR.…”

“…These signals account for 35.6% of the proton resonance in the sample (Table 2), although overlapping signals from other carbohydrates could also be included. In the 13 C NMR, characteristic levoglucosan signals can be easily observed at 102.5, 76.9, 73.7, 72.1, 71.6, and 65.2 ppm. Outside of those signals, the 13 C NMR supports the presence of several other sugars with several small peaks observable at similar chemical shifts to the levoglucosan peaks, indicating the presence of less concentrated but similarly structured molecules.…”

“…In the 13 C NMR, characteristic levoglucosan signals can be easily observed at 102.5, 76.9, 73.7, 72.1, 71.6, and 65.2 ppm. Outside of those signals, the 13 C NMR supports the presence of several other sugars with several small peaks observable at similar chemical shifts to the levoglucosan peaks, indicating the presence of less concentrated but similarly structured molecules. The non- by py-GC−MS (Figure S2b) indicates that additional thermal processing of this fraction releases small amounts of alkyl phenols and alkyl catechols as minor components in addition to levoglucosan and other sugars, confirming the presence of phenolic oligiomers.…”

“…MS spectra in other prominent peaks in the GC−MS chromatogram (see Figure S2a) suggested that other sugars and/or anhydrosugars were present, though they could not be identified. Levoglucosan could easily be identified in both the 1 H and 13 C NMR spectra (Figures S3 and S4) of fraction 1. The 1 H spectrum peaks at approximately 5.3, 4.4, 4.0, 3.6, 3.5, 3.32, and 3.30 ppm are readily assigned to levoglucosan.…”

“…Others have attempted to separate the oxygenated bio-oil into more fungible fractions. Distillation of fast-pyrolysis bio-oil has found little success because many compounds, such as acids, olefins, aldehydes, and phenols, are converted due to their instability and reactivity even at mild temperatures. , Further, a solid residue that is similar to coke is formed, which can result in a loss of up to 50 wt % of the organic liquid products as well as plugging problems due to the formation of a hardened liquid/solid slurry. ,, This fouling is especially concerning when fractional columns are used since regular cleaning of such equipment in an industrial operation would be unfeasible.…”