**3. Results and discussions**

#### **3.1. Centesimal and elemental characterization of açaí (***Euterpe oleracea***) seeds**

**Table 1** shows the centesimal and elemental characterization of açaí (*Euterpe oleracea*) seeds *in nature*. The experimental results obtained for moisture, proteins, and cellulose are according to those reported by Altman [9], while those for lipids, proteins, and fibers are according to those reported by Kabacknik and Roger [8]. In addition, the results for lipids and proteins are according to those reported by Tamiris et al. [7]. The centesimal characterization of açaí (*Euterpe oleracea*) seeds totalizes 98.07% (wt.) in dry basis, showing that summation (moisture, lipids, proteins, fibers, hemicellulose, cellulose, lignin, volatile matter, fixed carbon, and ash) is almost close to 100% (wt.). The summation of centesimal characterization of açaí seeds (moisture, lipids, proteins, fibers, ash, and nitrogen) reported by Tamiris et al. [7] is also close to 100% (wt.). The results for fibers are much higher than those reported by Tamiris et al. [7], who reported 85.69% (wt.) of carbohydrates, and much lower than those reported by Altman [9].

**3.3. Physicochemical characterization of bio-oil**

and 68.34 mm<sup>2</sup>

**Physicochemical analysis Cordeiro [6]** 

**Wet Basis**

1.0468 g/cm<sup>3</sup>

cm3

**Table 3** presents the physicochemical characterization of bio-oil obtained by pyrolysis of dried açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm. The bio-oil density and viscosity were

**Tamiris et al. [7]** 

**Dry Basis**

Moisture (%) 10.15 0.79 58.30 13.60 Lipids (%) 0.61 1.98 1.65 3.48 Proteins (%) 6.25 7.85 5.56 5.02 Fibers (%) 29.79 2.1 21.29 62.95 Hemicelluloses (%) 5.5 — — 14.19 Cellulose (%) 40.29 — — 39.83 Lignin (%) 4.00 — — 8.93 Volatile matter (%) 0.5 — — — Fixed carbon (%) 0.83 — — — Ash (%) 0.15 1.68 5.97 1.55 Nitrogen (%) — 1.26 — — Carbohydrate (%) — 85.69 — —

to similar data reported in the literature [35], where average density of wood bio-oil is 1.2 g/

and the kinematic viscosity of wood bio-oils at 50°C varies between 40 and 100 mm<sup>2</sup>

The acid value of bio-oil was 70.26 KOH/g, being the acidity due to the presence of oxygenates compounds, such as carboxylic acids, phenols, cresols, ketones, and aldehydes, as described in **Table 5**, confirming the results reported by Oasmaa et al. [36], who stated that acidity of fast pyrolysis bio-oil is mainly due to volatile carboxylic acids, but not only, as well as other

Mass balances and yields (distillates and raffinate) of fractional distillation of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm are illustrated in **Table 4**. The distillation of bio-oil yielded fossil fuel-like fractions (gasoline, kerosene, and light diesel) of 4.70, 28.21, and 22.35% (wt.), respectively, totalizing 55.26% (wt.), being according to similar results for distillation of bio-oil reported in the literature [22, 23, 25, 37]. Zheng and Wie [22], investigated the distillation of fast pyrolysis bio-oil at 80°C and 15 mmHg, obtaining a distilled bio-oil yield of 61% (wt.), being the oxygenates' content of distilled bio-oil 9.2% (wt.).

functional groups such as phenols, resin acids, and hydroxy acids [36].

**Table 1.** Centesimal and elemental characterization of Açaí (*Euterpe oleracea*, Mart) seeds *in nature*.

**pyrolysis of dried açaí (***Euterpe oleracea***, Mart) seeds**

**3.4. Mass balances, yields (distillates and raffinate) of fractional distillation, and physicochemical characterization of distillation fractions of bio-oil obtained by** 

/s, respectively. The density and kinematic viscosity are according

**Kabacknik and Roger [8]** 

**Altman [9] Wet Basis**

67

http://dx.doi.org/10.5772/intechopen.79546

**Wet Basis**

Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (*Euterpe oleracea*) Seeds

/s.

#### **3.2. Process parameters and overall steady state material balances of dried açaí (***Euterpe oleracea***, Mart) seeds pyrolysis**

The process conditions and steady state material balances of dried Açaí (*Euterpe oleracea*, Mart) seeds pyrolysis are shown in **Table 2**. The experimental results show that bio-oil, gas, water phase, and coke yields were 4.38, 29.39, and 35.67% (wt.), respectively. The bio-oil yield of 4.39% (wt.) is lower compared to similar data for bio-oil yield obtained by fast pyrolysis of forestry residues at 520°C reported in the literature [33, 34], ranging from 10 to 20% (wt.), and depends on the feedstock composition. The low bio-oil yield is probably due to the high fiber content, as illustrated in **Table 3**. The high yield of water phase is probably due to dehydration reactions along the pyrolysis process, as the initial moisture content is 10.15% (wt.), being the water phase yield of 29.39% (wt.) close to that of 28.0% (wt.), as reported in the literature [34].


**Table 1.** Centesimal and elemental characterization of Açaí (*Euterpe oleracea*, Mart) seeds *in nature*.

#### **3.3. Physicochemical characterization of bio-oil**

retention time, and compound identification were recorded for each peak analyzed according to the NIST (Standard Reference Database 1A, V14) mass spectra library, which is part of the software. The identification is made based on the similarity of the peak mass spectrum obtained with the spectra within the library database, included in the software. The contents of all identified oxygenates and hydrocarbons present in each sample were separated and the

The characterization of solid phase products (coke) obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale, was performed by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) according the equipment's and procedures described in detail elsewhere [31, 32].

**Table 1** shows the centesimal and elemental characterization of açaí (*Euterpe oleracea*) seeds *in nature*. The experimental results obtained for moisture, proteins, and cellulose are according to those reported by Altman [9], while those for lipids, proteins, and fibers are according to those reported by Kabacknik and Roger [8]. In addition, the results for lipids and proteins are according to those reported by Tamiris et al. [7]. The centesimal characterization of açaí (*Euterpe oleracea*) seeds totalizes 98.07% (wt.) in dry basis, showing that summation (moisture, lipids, proteins, fibers, hemicellulose, cellulose, lignin, volatile matter, fixed carbon, and ash) is almost close to 100% (wt.). The summation of centesimal characterization of açaí seeds (moisture, lipids, proteins, fibers, ash, and nitrogen) reported by Tamiris et al. [7] is also close to 100% (wt.). The results for fibers are much higher than those reported by Tamiris et al. [7], who reported 85.69% (wt.) of carbohydrates, and much lower than those reported

**2.5. Morphology of solid phase products of açaí seeds (***Euterpe oleracea***, Mart)**

**3.1. Centesimal and elemental characterization of açaí (***Euterpe oleracea***) seeds**

**3.2. Process parameters and overall steady state material balances of dried açaí** 

The process conditions and steady state material balances of dried Açaí (*Euterpe oleracea*, Mart) seeds pyrolysis are shown in **Table 2**. The experimental results show that bio-oil, gas, water phase, and coke yields were 4.38, 29.39, and 35.67% (wt.), respectively. The bio-oil yield of 4.39% (wt.) is lower compared to similar data for bio-oil yield obtained by fast pyrolysis of forestry residues at 520°C reported in the literature [33, 34], ranging from 10 to 20% (wt.), and depends on the feedstock composition. The low bio-oil yield is probably due to the high fiber content, as illustrated in **Table 3**. The high yield of water phase is probably due to dehydration reactions along the pyrolysis process, as the initial moisture content is 10.15% (wt.), being the water phase yield of 29.39% (wt.) close to that of 28.0% (wt.), as reported in the literature [34].

chemical composition of each experiment was estimated.

**3. Results and discussions**

66 Fractionation

by Altman [9].

**(***Euterpe oleracea***, Mart) seeds pyrolysis**

**Table 3** presents the physicochemical characterization of bio-oil obtained by pyrolysis of dried açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm. The bio-oil density and viscosity were 1.0468 g/cm<sup>3</sup> and 68.34 mm<sup>2</sup> /s, respectively. The density and kinematic viscosity are according to similar data reported in the literature [35], where average density of wood bio-oil is 1.2 g/ cm3 and the kinematic viscosity of wood bio-oils at 50°C varies between 40 and 100 mm<sup>2</sup> /s. The acid value of bio-oil was 70.26 KOH/g, being the acidity due to the presence of oxygenates compounds, such as carboxylic acids, phenols, cresols, ketones, and aldehydes, as described in **Table 5**, confirming the results reported by Oasmaa et al. [36], who stated that acidity of fast pyrolysis bio-oil is mainly due to volatile carboxylic acids, but not only, as well as other functional groups such as phenols, resin acids, and hydroxy acids [36].

#### **3.4. Mass balances, yields (distillates and raffinate) of fractional distillation, and physicochemical characterization of distillation fractions of bio-oil obtained by pyrolysis of dried açaí (***Euterpe oleracea***, Mart) seeds**

Mass balances and yields (distillates and raffinate) of fractional distillation of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm are illustrated in **Table 4**. The distillation of bio-oil yielded fossil fuel-like fractions (gasoline, kerosene, and light diesel) of 4.70, 28.21, and 22.35% (wt.), respectively, totalizing 55.26% (wt.), being according to similar results for distillation of bio-oil reported in the literature [22, 23, 25, 37]. Zheng and Wie [22], investigated the distillation of fast pyrolysis bio-oil at 80°C and 15 mmHg, obtaining a distilled bio-oil yield of 61% (wt.), being the oxygenates' content of distilled bio-oil 9.2% (wt.).

#### 68 Fractionation


*3.4.1. Physicochemical characterization of distillation fractions (gasoline, kerosene, and light* 

**OLP Gas Raffinate Distillates (g) Yield (wt.%)**

450°C 136.84 0 40.98 20.26 6.43 38.60 30.59 0 14.80 4.70 28.21 22.35 0

**Table 4.** Mass balances and yields (Distillates and Raffinate) of fractional distillation of bio-oil obtained by pyrolysis of

**O G K LD HD H2**

Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (*Euterpe oleracea*) Seeds

sene and light diesel-like fractions increase with increasing boiling temperature.

*3.5.1. Qualitative analyses of chemical functions in bio-oil by FT-IR spectroscopy*

**3.5. Qualitative and compositional analyses of bio-oil**

**(g) (g) (g) H2**

G = gasoline, K = kerosene, LD = light diesel, HD = heavy diesel.

dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale.

of aliphatic compounds, associated to methylene (CH<sup>2</sup>

) and methyl (CH<sup>3</sup>

band of axial deformation at 3435 cm−<sup>1</sup>

bio-oil exhibit between 1455 and 1465 cm−<sup>1</sup>

of C–H bonds in methyl group (CH<sup>3</sup>

The spectrum of bio-oil identified at 1377 cm−<sup>1</sup>

peaks between 2921 and 2964 cm−<sup>1</sup>

and 1747 cm−<sup>1</sup>

(CH<sup>2</sup>

tion of methylene (CH<sup>2</sup>

The physicochemical characterization of distillation fractions (gasoline: 80–175°C, kerosene: 175–235°C, and light diesel-like fraction: 235–305°C) of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm is shown in **Table 5**. It can be observed that acidity of distillation fractions (gasoline, kerosene, and light diesel-like) increases with increasing boiling temperature, showing a drastic decrease compared to the acidity of raw bio-oil. This is probably due to the high concentration of higher boiling-point compounds in the distillate fractions, such as p-cresol, o-cresol, guaiacol, phenol, and furans, which increases with the increasing boiling temperature [23]. In addition, the densities and viscosities of kero-

**Figure 3** illustrates the FT-IR analysis of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The identification of absorption bands/ peaks done according to previous studies [31, 38, 39]. The spectrum of bio-oil presents a wide

indicating probably the presence of carboxylic acids. The spectra of bio-oil exhibit intense

firms the presence of hydrocarbons [31, 38]. It has been observed that for bio-oil, an intense axial deformation band, characteristic of carbonyl (C=O) groups, with the peaks at 1742, 1745,

are characteristic of an angular deformation outside the plane of C–H bonds, indicating the presence of alkenes [31, 38]. The spectra of bio-oil exhibit bands between 721 and 667 cm−<sup>1</sup>

peaks characteristic of an angular deformation outside the plane of C–H bonds in methylene

) group, indicating the presence of olefins [31, 38]. The characteristic peaks of phenols

and between 2858 and 2964 cm−<sup>1</sup>

, probably associated to a ketone and/or carboxylic acids [31, 38]. The spectra of

) [31, 38]. The peaks between 995 and 905 cm−<sup>1</sup>

, characteristic of O–H intramolecular hydrogen bond,

) and methyl (CH<sup>3</sup>

, a characteristic asymmetrical deformation vibra-

) groups, indicating the presence of alkanes [31, 38].

, a band of symmetrical angular deformation

, indicating the presence

**O G K LD HD**

69

http://dx.doi.org/10.5772/intechopen.79546

) groups. This con-

for bio-oil,

,

*diesel-like fractions)*

**Distillation: vigreux column**

**Table 2.** Process parameters and overall steady state material balances of dried Açaí (*Euterpe oleracea*, Mart) seeds pyrolysis at 450°C and 1.0 atm, in pilot scale.


**Table 3.** Physicochemical characterization of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale.

Zhang et al. [23] investigated the atmospheric distillation of fast pyrolysis bio-oil and reported an accumulated distillate of 51.86% (wt.). The major organic compounds identified in distillate fractions include phenols, guaiacols, furans, and volatile carboxylic acids (acetic acid and propanoic acid) were also observed in raw bio-oil [23]. In addition, Zhang et al. [23] reported that as the distillation temperature reached 240°C, condensation reactions take place, generating water. Elkasabi et al. [25] reported organic yields from distillation of tail-gas reactive pyrolysis (TGRP) bio-oil ranging from 55 to 65% (wt.).


**Table 4.** Mass balances and yields (Distillates and Raffinate) of fractional distillation of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale.

#### *3.4.1. Physicochemical characterization of distillation fractions (gasoline, kerosene, and light diesel-like fractions)*

The physicochemical characterization of distillation fractions (gasoline: 80–175°C, kerosene: 175–235°C, and light diesel-like fraction: 235–305°C) of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm is shown in **Table 5**. It can be observed that acidity of distillation fractions (gasoline, kerosene, and light diesel-like) increases with increasing boiling temperature, showing a drastic decrease compared to the acidity of raw bio-oil. This is probably due to the high concentration of higher boiling-point compounds in the distillate fractions, such as p-cresol, o-cresol, guaiacol, phenol, and furans, which increases with the increasing boiling temperature [23]. In addition, the densities and viscosities of kerosene and light diesel-like fractions increase with increasing boiling temperature.

#### **3.5. Qualitative and compositional analyses of bio-oil**

Zhang et al. [23] investigated the atmospheric distillation of fast pyrolysis bio-oil and reported an accumulated distillate of 51.86% (wt.). The major organic compounds identified in distillate fractions include phenols, guaiacols, furans, and volatile carboxylic acids (acetic acid and propanoic acid) were also observed in raw bio-oil [23]. In addition, Zhang et al. [23] reported that as the distillation temperature reached 240°C, condensation reactions take place, generating water. Elkasabi et al. [25] reported organic yields from distillation of tail-gas reactive pyrolysis

**Table 3.** Physicochemical characterization of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at

**Table 2.** Process parameters and overall steady state material balances of dried Açaí (*Euterpe oleracea*, Mart) seeds

**Bio-oil**

**450**

**Physicochemical properties 450°C ANP N° 65**

**Process parameters Cracking temperature (°C)**

O) (kg) 10,133

Mass of Açaí (kg) 30

Cracking time (min) 150 Mechanical stirrer speed (rpm) 0 Initial cracking temperature (°C) 179

Mass of Coke (kg) 10,700 Mass of OLP (kg) 1316

Mass of gas (kg) 9167 Yield of OLP (kg) 4.39 Yield of coke (kg) 35.67

Yield of Gas (kg) 30.56

O (kg) 8.816

O (kg) 29.39

Acid value (mg KOH/g) 70.26 — Refractive index (—) ND ν (cSt) 68.34 2.0–4.5

ANP: Brazilian National Petroleum Agency, resolution N° 65 (specification of diesel S10).

) 1.0468 0.82–0.85

(TGRP) bio-oil ranging from 55 to 65% (wt.).

ρ (g/cm<sup>3</sup>

Mass of GLP (kg)

68 Fractionation

Mass of H<sup>2</sup>

Yield of H<sup>2</sup>

Mass of aqueous phase (OLP + H<sup>2</sup>

pyrolysis at 450°C and 1.0 atm, in pilot scale.

450°C and 1.0 atm, in pilot scale.

#### *3.5.1. Qualitative analyses of chemical functions in bio-oil by FT-IR spectroscopy*

**Figure 3** illustrates the FT-IR analysis of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The identification of absorption bands/ peaks done according to previous studies [31, 38, 39]. The spectrum of bio-oil presents a wide band of axial deformation at 3435 cm−<sup>1</sup> , characteristic of O–H intramolecular hydrogen bond, indicating probably the presence of carboxylic acids. The spectra of bio-oil exhibit intense peaks between 2921 and 2964 cm−<sup>1</sup> and between 2858 and 2964 cm−<sup>1</sup> , indicating the presence of aliphatic compounds, associated to methylene (CH<sup>2</sup> ) and methyl (CH<sup>3</sup> ) groups. This confirms the presence of hydrocarbons [31, 38]. It has been observed that for bio-oil, an intense axial deformation band, characteristic of carbonyl (C=O) groups, with the peaks at 1742, 1745, and 1747 cm−<sup>1</sup> , probably associated to a ketone and/or carboxylic acids [31, 38]. The spectra of bio-oil exhibit between 1455 and 1465 cm−<sup>1</sup> , a characteristic asymmetrical deformation vibration of methylene (CH<sup>2</sup> ) and methyl (CH<sup>3</sup> ) groups, indicating the presence of alkanes [31, 38]. The spectrum of bio-oil identified at 1377 cm−<sup>1</sup> , a band of symmetrical angular deformation of C–H bonds in methyl group (CH<sup>3</sup> ) [31, 38]. The peaks between 995 and 905 cm−<sup>1</sup> for bio-oil, are characteristic of an angular deformation outside the plane of C–H bonds, indicating the presence of alkenes [31, 38]. The spectra of bio-oil exhibit bands between 721 and 667 cm−<sup>1</sup> , peaks characteristic of an angular deformation outside the plane of C–H bonds in methylene (CH<sup>2</sup> ) group, indicating the presence of olefins [31, 38]. The characteristic peaks of phenols


p-cresol. The peaks appearing in the range of 1000–1200 cm−<sup>1</sup>

bond, associated with those in a lower range of 650–750 cm−<sup>1</sup>

(phenols, cresols, carboxylic acids, ketones, furans, etc.).

*3.5.2. Compositional analyses of bio-oil by GC-MS*

the presence of furans, coupled with peaks in the 3000–3100 and 1400–1600 cm−<sup>1</sup>

the presence of aromatic rings in the form of C–H and C=C stretching, respectively, corresponding to the presence of furans (benzofuran) [39]. The FT-IR analysis of bio-oil identifies the presence of hydrocarbons (alkanes, alkenes, aromatic hydrocarbons, etc.,) and oxygenates

Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (*Euterpe oleracea*) Seeds

**Figure 4** illustrates the chromatogram of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The classes of compounds, summation of peak areas, CAS numbers, and retention times of chemical compounds are identified by GC-MS described in **Table 6**. The chemical compounds identified by GC-MS were hydrocarbons (alkanes, alkenes, aromatic hydrocarbons, and cycloalkenes) and oxygenates (esters, phenols, cresols, carboxylic acids, ketones, furans, and aldehydes). The bio-oil is composed

**Figure 4.** GC-MS of bio-oil obtained by pyrolysis of Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale.

indicate the presence of C–O–C

http://dx.doi.org/10.5772/intechopen.79546

, from –CH=CH– bonds, showing

, suggesting

71

I.A = acid value, I.R = refractive index, SNA = amount of sample not enough for analysis.

**Table 5.** Physicochemical characterization of distillation fractions (gasoline: 80–175°C, kerosene: 175–235°C, and light diesel-like fraction: 235–305°C) of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale.

**Figure 3.** FT-IR of Açaí (*Euterpe oleracea*, Mart) seeds bio-oil after pyrolysis at 450°C and 1.0 atm, in pilot scale.

at 1510 cm−<sup>1</sup> corresponded to the C=C aromatic ring vibrations [39]. The peaks at 1240 and 1180 cm−<sup>1</sup> corresponded to the C–C–O asymmetric stretch and C–H in-plane deformations, respectively, while the 990 and 747 cm−<sup>1</sup> peaks belonged to the C–H out-of-plane vibrations. The frequency due to OH in-plane bonding vibration in phenols, in general, lies in the region 1150–1250 cm−<sup>1</sup> . The 1500 cm−<sup>1</sup> vibration is a triplet appearing at 1515 and 1460 cm−<sup>1</sup> , corresponding probably to the presence of p-cresol and m-cresol, respectively. The OH deformation and C–O stretching vibrations in phenols are close to each other, and therefore they are strongly coupled. They fall above 1100 cm−<sup>1</sup> and extend up to 1330 cm−<sup>1</sup> . A broad absorption is observed in this region due to the presence of numerous phenols. The out-of-plane hydrogen vibrations appearing in the region 900–675 cm−<sup>1</sup> suggest the presence of m-cresol and p-cresol. The peaks appearing in the range of 1000–1200 cm−<sup>1</sup> indicate the presence of C–O–C bond, associated with those in a lower range of 650–750 cm−<sup>1</sup> , from –CH=CH– bonds, showing the presence of furans, coupled with peaks in the 3000–3100 and 1400–1600 cm−<sup>1</sup> , suggesting the presence of aromatic rings in the form of C–H and C=C stretching, respectively, corresponding to the presence of furans (benzofuran) [39]. The FT-IR analysis of bio-oil identifies the presence of hydrocarbons (alkanes, alkenes, aromatic hydrocarbons, etc.,) and oxygenates (phenols, cresols, carboxylic acids, ketones, furans, etc.).

#### *3.5.2. Compositional analyses of bio-oil by GC-MS*

at 1510 cm−<sup>1</sup>

1150–1250 cm−<sup>1</sup>

respectively, while the 990 and 747 cm−<sup>1</sup>

. The 1500 cm−<sup>1</sup>

strongly coupled. They fall above 1100 cm−<sup>1</sup>

gen vibrations appearing in the region 900–675 cm−<sup>1</sup>

1180 cm−<sup>1</sup>

ρ (g/cm<sup>3</sup>

70 Fractionation

1.0 atm, in pilot scale.

corresponded to the C=C aromatic ring vibrations [39]. The peaks at 1240 and

peaks belonged to the C–H out-of-plane vibrations.

, cor-

. A broad absorption

suggest the presence of m-cresol and

vibration is a triplet appearing at 1515 and 1460 cm−<sup>1</sup>

and extend up to 1330 cm−<sup>1</sup>

corresponded to the C–C–O asymmetric stretch and C–H in-plane deformations,

The frequency due to OH in-plane bonding vibration in phenols, in general, lies in the region

**Figure 3.** FT-IR of Açaí (*Euterpe oleracea*, Mart) seeds bio-oil after pyrolysis at 450°C and 1.0 atm, in pilot scale.

**Physicochemical properties 450° C ANP N° 65**

ν (cSt) SNA 4.29 9.05 **2.0–4.5**

I.A (mg KOH/g) 19.94 61.08 64.78 I.R (−) 1455 1479 1497

I.A = acid value, I.R = refractive index, SNA = amount of sample not enough for analysis.

) SNA 0.9191 0.9816 **0.82–0.85**

**Table 5.** Physicochemical characterization of distillation fractions (gasoline: 80–175°C, kerosene: 175–235°C, and light diesel-like fraction: 235–305°C) of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and

**G K LD**

responding probably to the presence of p-cresol and m-cresol, respectively. The OH deformation and C–O stretching vibrations in phenols are close to each other, and therefore they are

is observed in this region due to the presence of numerous phenols. The out-of-plane hydro-

**Figure 4** illustrates the chromatogram of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The classes of compounds, summation of peak areas, CAS numbers, and retention times of chemical compounds are identified by GC-MS described in **Table 6**. The chemical compounds identified by GC-MS were hydrocarbons (alkanes, alkenes, aromatic hydrocarbons, and cycloalkenes) and oxygenates (esters, phenols, cresols, carboxylic acids, ketones, furans, and aldehydes). The bio-oil is composed

**Figure 4.** GC-MS of bio-oil obtained by pyrolysis of Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale.


by 21.52% (area) hydrocarbons (2.12% alkenes, 7.52% alkanes, 10.04% aromatic hydrocarbons, and 1.85% cycloalkenes), and 78.48% (area) oxygenates (4.06% esters, 8.52% carboxylic acids, 3.53% ketones, 35.16% phenols, 20.52% cresols, 5.75% furans, and 0.91% aldehydes). The presence of carboxylic acids, as well as phenols and cresols, but not only, confers the high acidity

**Table 6.** Classes of compounds, summation of peak areas, CAS numbers, and retention times of chemical compounds identified by GC-MS of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm,

**Class of compounds: chemical compounds RT (min) CAS ω<sup>i</sup>**

Phenol, 2,6-dimethyl 10,805 576–26–1 1991 Phenol, 2,4-dimethyl 11,469 105–67–9 2034 Phenol, 2,5-dimethyl 11,502 95–87–4 2215 Phenol, 3,4-dimethyl 11,821 95–65–8 3845 Phenol, 4-ethyl-2-methoxy 13,571 2785–89–9 4567 *Ʃ (Area.%) =* **35,167**

Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (*Euterpe oleracea*) Seeds

p-Cresol 9818 108–39–4 6331 m-Cresol 10,198 106–44–5 11,054 Cresol 12,210 93–51–3 3141 *Ʃ (Area.%) =* **20,526**

Benzofuran, 2-methyl 10,879 4265–26–2 1879 Furan, 2-(2 furanylmethyl)-5-methyl 11,946 13,678–51–8 2089 Benzofuran, 4,7-dimethyl 12,700 28,715–26–6 1783 *Ʃ (Area.%) =* **5751**

Cinnamaldehyde, β-methyl- 12,654 1196–67–4 0.910 *Ʃ (Area.%) =* **0.910**

The chemical composition of bio-oil is according to similar bio-oil compositions reported in the literature [22, 23, 25, 26, 36, 37], showing the presence of hydrocarbons, phenols, cresols, furans, carboxylic acids, esters, among other classes of chemical compounds. The hydrocarbons identified in bio-oil by GC-MS present carbon chain length between C11 and C15 with following carbon chain lengths, alkenes C13, alkanes C11–C15, and cycloalkenes C13. The chemical composition of bio-oil indicates the presence of heavy gasoline compounds with C11 (C5

kerosene-like fractions (C11–C12), and light diesel-like fractions (C13–C15), as observed by frac-

–C11),

**% (Area)**

73

http://dx.doi.org/10.5772/intechopen.79546

of bio-oil, as described in **Table 3**.

**450°C**

**Cresols**

**Furans**

**Aldehydes**

in pilot scale.

tional distillation illustrated in **Table 4**.


**450°C**

72 Fractionation

**Alkanes**

**Alkenes**

**Cycloalkenes**

**Esters**

**Carboxylic acids**

**Ketones**

**Phenols**

**Aromatic hydrocarbons**

**Class of compounds: chemical compounds RT (min) CAS ω<sup>i</sup>**

Undecane 10,622 1120–21–4 1124 Tridecane 13,870 629–50–5 2481 Pentadecane 16,744 629–62–9 2290 Dodecane, 5,8-diethyl 19,326 24.251–86–3 1626 **Ʃ (Area.%) = 7521**

6-Tridecene, (Z)- 1626 6508–77–6 2118 *Ʃ (Area.%) =* **2118**

Megastigma-4,6(E), 8 (Z)-trien 13,440 5298–13–5 1847 *Ʃ (Area.%) =* **1847**

Naphthalene 12,262 91–20–3 4399 Naphthalene, 1-methyl 14,046 90–12–0 2390 1H-Indene, 1-ethylidene 14,296 2471–83–2 3249 *Ʃ (Area.%) =* **10,038**

Undecanoic acid, 10-methyl-, methyl ester 17,049 5129–56–6 1096 Methyl tetradecanoate 19,620 124–10–7 2969 *Ʃ (Area.%) =* **4065**

Dodecanoic acid 17,648 334–48–5 4307 Tetradecanoic acid 20,677 544–63–8 4216 *Ʃ (Area.%) =* **8523**

2-Pentanone, 4-hydroxy-4-methyl 5886 123–42–2 1878 2-Cyclopenten-1-one, 2,3-dimethyl 9552 1121–05–7 1655 *Ʃ (Area.%) =* **3533**

Phenol 8469 108–95–2 15,932 Phenol, 2-methoxy 10,446 90–05–1 4583

**% (Area)**

**Table 6.** Classes of compounds, summation of peak areas, CAS numbers, and retention times of chemical compounds identified by GC-MS of bio-oil obtained by pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale.

by 21.52% (area) hydrocarbons (2.12% alkenes, 7.52% alkanes, 10.04% aromatic hydrocarbons, and 1.85% cycloalkenes), and 78.48% (area) oxygenates (4.06% esters, 8.52% carboxylic acids, 3.53% ketones, 35.16% phenols, 20.52% cresols, 5.75% furans, and 0.91% aldehydes). The presence of carboxylic acids, as well as phenols and cresols, but not only, confers the high acidity of bio-oil, as described in **Table 3**.

The chemical composition of bio-oil is according to similar bio-oil compositions reported in the literature [22, 23, 25, 26, 36, 37], showing the presence of hydrocarbons, phenols, cresols, furans, carboxylic acids, esters, among other classes of chemical compounds. The hydrocarbons identified in bio-oil by GC-MS present carbon chain length between C11 and C15 with following carbon chain lengths, alkenes C13, alkanes C11–C15, and cycloalkenes C13. The chemical composition of bio-oil indicates the presence of heavy gasoline compounds with C11 (C5 –C11), kerosene-like fractions (C11–C12), and light diesel-like fractions (C13–C15), as observed by fractional distillation illustrated in **Table 4**.

#### **3.6. Morphology of solid phase products of açaí seeds (***Euterpe oleracea***, Mart)**

#### *3.6.1. SEM analysis of solid phase*

The scanning electron microscopies of açaí (*Euterpe oleracea*, Mart) seeds *in nature* and after pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm are shown in **Figures 5** and **6**, respectively. SEM was applied to investigate changes on the vegetal surface structure during the pyrolysis process. By comparison of SEM images of açaí seeds *in nature* and after pyrolysis, it can be observed for açaí seeds *in nature* that an aggregate, amorphous and homogeneous structure with irregular shapes dominates, showing the pyrolysis process had a drastic effect on the vegetal morphology, as the vegetal structure differs largely from its original microscopic characteristics, as observed in **Figure 6**, as all the plant cell walls are constituted by cavities. The pyrolysis process produced an aggregate, amorphous solid phase, heterogeneous structure with irregular shapes, being the morphology after pyrolysis completely different compared to the characteristics of original vegetal surface structure. In addition, according to **Table 7**, the carbonization grade is higher, showing that temperature has caused substantial changes on the morphological structure of açaí (*Euterpe oleracea*, Mart)

Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (*Euterpe oleracea*) Seeds

http://dx.doi.org/10.5772/intechopen.79546

75

**Table 7** illustrates the energy dispersive X-ray spectroscopy of açaí seeds *in nature* and after pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The results show that after pyrolysis the carbon content increases, while that of oxygen decreases, compared to those of açaí seeds *in nature*, showing that carbonization grade is higher. Finally, the morphological structure of açaí (*Euterpe oleracea*, Mart) seeds after pyrolysis presents open cavities caused by destruction of the plant cell walls, and may be probably used as a

**Table 7** illustrates the energy dispersive X-ray spectroscopy of açaí seeds *in nature* and after pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm by EDX technique. The results show that carbon content increases from 79.28 to 89.98% (wt.), showing a carbonization grad of 13.5%, while that of oxygen decreases from 20.71 to 6.94% (wt.) along with the pyrolysis process. The EDX also identified the presence of K and S in açaí seeds *in nature*.

**Figure 7** shows the XRD analysis of solid phase products obtained by pyrolysis of Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The results confirm the presence of

**450°C Açaí seeds**

**Chemical elements Mass (wt.%) Atomic mass (wt.%) SD Mass (wt.%) Atomic mass (wt.%) SD** C 89.98 93.55 4.64 79.28 83.60 4.85 O 6.94 5.41 0.54 20.71 16.39 1.50 Mg — — — — — — Si — — — — — — K 2.45 2.45 0.07 — — — S 0.60 0.60 0.04 — — — Al — — — — — —

**Table 7.** Percentages in *Atomic Mass* of dried Açaí (*Euterpe oleracea*, Mart) seeds *in nature* and after pyrolysis at 450°C and

seeds *in nature* by destructing and/or degrading the plant cell walls.

bio-adsorbent.

*3.6.2. EDX analysis of solid phase*

*3.6.3. XRD analysis of solid phase*

SD = standard deviation.

1.0 atm by EDX technique.

**Figure 5.** SEM of Açaí (*Euterpe oleracea*, Mart) seeds *in nature*.

**Figure 6.** SEM of Açaí (*Euterpe oleracea*, Mart) seeds coke after pyrolysis at 450°C and 1.0 atm, in pilot scale.

and homogeneous structure with irregular shapes dominates, showing the pyrolysis process had a drastic effect on the vegetal morphology, as the vegetal structure differs largely from its original microscopic characteristics, as observed in **Figure 6**, as all the plant cell walls are constituted by cavities. The pyrolysis process produced an aggregate, amorphous solid phase, heterogeneous structure with irregular shapes, being the morphology after pyrolysis completely different compared to the characteristics of original vegetal surface structure. In addition, according to **Table 7**, the carbonization grade is higher, showing that temperature has caused substantial changes on the morphological structure of açaí (*Euterpe oleracea*, Mart) seeds *in nature* by destructing and/or degrading the plant cell walls.

**Table 7** illustrates the energy dispersive X-ray spectroscopy of açaí seeds *in nature* and after pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The results show that after pyrolysis the carbon content increases, while that of oxygen decreases, compared to those of açaí seeds *in nature*, showing that carbonization grade is higher. Finally, the morphological structure of açaí (*Euterpe oleracea*, Mart) seeds after pyrolysis presents open cavities caused by destruction of the plant cell walls, and may be probably used as a bio-adsorbent.

#### *3.6.2. EDX analysis of solid phase*

**3.6. Morphology of solid phase products of açaí seeds (***Euterpe oleracea***, Mart)**

**Figure 6.** SEM of Açaí (*Euterpe oleracea*, Mart) seeds coke after pyrolysis at 450°C and 1.0 atm, in pilot scale.

The scanning electron microscopies of açaí (*Euterpe oleracea*, Mart) seeds *in nature* and after pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm are shown in **Figures 5** and **6**, respectively. SEM was applied to investigate changes on the vegetal surface structure during the pyrolysis process. By comparison of SEM images of açaí seeds *in nature* and after pyrolysis, it can be observed for açaí seeds *in nature* that an aggregate, amorphous

*3.6.1. SEM analysis of solid phase*

74 Fractionation

**Figure 5.** SEM of Açaí (*Euterpe oleracea*, Mart) seeds *in nature*.

**Table 7** illustrates the energy dispersive X-ray spectroscopy of açaí seeds *in nature* and after pyrolysis of dried Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm by EDX technique. The results show that carbon content increases from 79.28 to 89.98% (wt.), showing a carbonization grad of 13.5%, while that of oxygen decreases from 20.71 to 6.94% (wt.) along with the pyrolysis process. The EDX also identified the presence of K and S in açaí seeds *in nature*.

#### *3.6.3. XRD analysis of solid phase*

**Figure 7** shows the XRD analysis of solid phase products obtained by pyrolysis of Açaí (*Euterpe oleracea*, Mart) seeds at 450°C and 1.0 atm, in pilot scale. The results confirm the presence of


**Table 7.** Percentages in *Atomic Mass* of dried Açaí (*Euterpe oleracea*, Mart) seeds *in nature* and after pyrolysis at 450°C and 1.0 atm by EDX technique.

The FT-IR analysis of bio-oil identifies the presence of hydrocarbons (alkanes, alkenes, aromatic hydrocarbons, etc.) and oxygenates (phenols, cresols, carboxylic acids, ketones, furans, etc.). The bio-oil is composed by 21.52% (area) hydrocarbons (2.12% alkenes, 7.52% alkanes, 10.04% aromatic hydrocarbons, and 1.85% cycloalkenes), and 78.48% (area) oxygenates (4.06% esters, 8.52% carboxylic acids, 3.53% ketones, 35.16% phenols, 20.52% cresols, 5.75% furans, and 0.91% aldehydes). The presence of carboxylic acids, as well as phenols and

The pyrolysis process produced an aggregate, amorphous solid phase, heterogeneous structure with irregular shapes, being the morphology after pyrolysis completely different compared to the characteristics of original vegetal surface structure. In addition, the temperature has caused substantial changes on the morphological structure of açaí (*Euterpe oleracea*, Mart) seeds *in nature* by destructing and/or degrading the plant cell walls. The results of EDX show that carbon content increases from 79.28 to 89.98% (wt.), showing a carbonization grad of 13.5%, while that of oxygen decreases from 20.71 to 6.94% (wt.) along with the pyrolysis process. The results of EDX confirm the presence of three crystalline phases: (1) graphite (C); (2) cristobalite

26.52 (ICDD: 00-025-0284). The pyrolysis favors the formation of mineralogical phase graphite.

The fractional distillation makes it possible to obtain fossil fuel-like fractions (gasoline, kerosene, and light diesel) rich in hydrocarbons, based on the boiling temperature of

Douglas Alberto Rocha de Castro1,2,3, Haroldo Jorge da Silva Ribeiro1,2,

Anderson M. Pereira1,2,4, W. G. dos Santos1,2,4, Marcelo Costa Santos1,2,

, Luiz Eduardo Pizarro Borges6

, Jose Otavio Carrera Silva Junior<sup>3</sup>

1 Laboratory of Separation Processes and Applied Thermodynamic (TERM@), Faculty of

2 Graduate Program of Natural Resources Engineering-UFPA, Belém, Pará, Brazil

6 Laboratory of Catalyst Preparation and Catalytic Cracking, Section of Chemical

3 Laboratory of Pharmaceutical and Cosmetic Research and Development, Faculty of

Caio Campos Ferreira1,2, Márcio de Andrade Cordeiro<sup>1</sup>

\*Address all correspondence to: machado@ufpa.br

Chemical Engineering-UFPA, Belém, Pará, Brazil

4 Faculty of Agricultural Sciences-UFAM, Coroado, Brazil

5 Faculty of Chemical Engineering-UEA, Manaus, Amazonas, Brazil

Pharmacy-UFPA, Belém, Pará, Brazil

Engineering-IME, Rio de Janeiro, RJ, Brazil

), being graphite the peak of high intensity (100%) on the position 2:

Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (*Euterpe oleracea*) Seeds

http://dx.doi.org/10.5772/intechopen.79546

77

, Lauro Henrique Hamoy Guerreiro<sup>1</sup>

,

, R. Lopes e Oliveira<sup>5</sup>

and Nélio Teixeira Machado1,2\*

,

cresols, but not only, confers the high acidity of bio-oil, as described in **Table 3**.

(SiO<sup>2</sup>

hydrocarbons.

**Author details**

Sergio Duvoisin<sup>5</sup>

Fernanda B. de Carvalho<sup>3</sup>

); (3) quartz (SiO<sup>2</sup>

**Figure 7.** XRD of Açaí (*Euterpe oleracea*, Mart) seeds coke after pyrolysis at 450°C and 1.0 atm, in pilot scale.

three crystalline phases: (1) graphite (C) with a peak of high intensity (100%) on the position 2: 26.52 (ICDD: 00–025-0284); (2) cristobalite (SiO2) with peaks of medium intensity on the positions 2: 15.07 (71.53%) (ICDD: 01-077-1316); (3) quartz (SiO<sup>2</sup> ) with a peak of high intensity on the position 2: 20.40 (90.30%) (ICDD: 01-089-8940). The pyrolysis favors the formation of mineralogical phase graphite (C). This is according to the results described in Section 3.2.2, whereas a carbonization takes place during the pyrolysis process.

#### **4. Conclusions**

The experimental results show that bio-oil, gas, water phase, and coke yields were 4.38, 30.56, 29.39, and 35.67% (wt.), respectively. The bio-oil yield of 4.38% (wt.) is lower compared to similar data for bio-oil yield obtained by fast pyrolysis of forestry residues at 520°C reported in the literature [33, 34], ranging from 10 to 20% (wt.). The bio-oil density and viscosity were 1.0468 g/cm<sup>3</sup> and 68.34 mm<sup>2</sup> /s, respectively, being according to similar data reported in the literature [35]. The acid value of bio-oil was 70.26 KOH/g, showing the presence of oxygenates compounds, such as carboxylic acids, phenols, cresols, ketones, and aldehydes, confirming the results reported by Oasmaa et al. [36].

The distillation of bio-oil yielded fossil fuel-like fractions (gasoline, kerosene, and light diesel) of 4.70, 28.21, and 22.35% (wt.), respectively, totalizing 55.26% (wt.), being the results according to similar studies for distillation of bio-oil reported in the literature [22, 23, 25, 37]. The acidity of distillation fractions (gasoline, kerosene, and light diesel-like) increases with increasing boiling temperature, showing a drastic decrease compared to the acidity of raw bio-oil. This i probably due to the high concentration of higher boiling-point compounds in the distillate fractions, such as p-cresol, o-cresol, guaiacol, phenol, and furans [23].

The FT-IR analysis of bio-oil identifies the presence of hydrocarbons (alkanes, alkenes, aromatic hydrocarbons, etc.) and oxygenates (phenols, cresols, carboxylic acids, ketones, furans, etc.). The bio-oil is composed by 21.52% (area) hydrocarbons (2.12% alkenes, 7.52% alkanes, 10.04% aromatic hydrocarbons, and 1.85% cycloalkenes), and 78.48% (area) oxygenates (4.06% esters, 8.52% carboxylic acids, 3.53% ketones, 35.16% phenols, 20.52% cresols, 5.75% furans, and 0.91% aldehydes). The presence of carboxylic acids, as well as phenols and cresols, but not only, confers the high acidity of bio-oil, as described in **Table 3**.

The pyrolysis process produced an aggregate, amorphous solid phase, heterogeneous structure with irregular shapes, being the morphology after pyrolysis completely different compared to the characteristics of original vegetal surface structure. In addition, the temperature has caused substantial changes on the morphological structure of açaí (*Euterpe oleracea*, Mart) seeds *in nature* by destructing and/or degrading the plant cell walls. The results of EDX show that carbon content increases from 79.28 to 89.98% (wt.), showing a carbonization grad of 13.5%, while that of oxygen decreases from 20.71 to 6.94% (wt.) along with the pyrolysis process. The results of EDX confirm the presence of three crystalline phases: (1) graphite (C); (2) cristobalite (SiO<sup>2</sup> ); (3) quartz (SiO<sup>2</sup> ), being graphite the peak of high intensity (100%) on the position 2: 26.52 (ICDD: 00-025-0284). The pyrolysis favors the formation of mineralogical phase graphite.

The fractional distillation makes it possible to obtain fossil fuel-like fractions (gasoline, kerosene, and light diesel) rich in hydrocarbons, based on the boiling temperature of hydrocarbons.
