**2. Materials and methods**

#### **2.1. Materials**

**1. Introduction**

62 Fractionation

CO<sup>2</sup>

etable species use and store CO<sup>2</sup>

crops, the new growing vegetable species can use the CO<sup>2</sup>

carbon dioxide cycle, as reported in the literature by Kelli et al. [14].

During the processing of açaí juice from açaí (*Euterpe oleracea*, Mart) seeds *in nature*, a native palm of natural occurrence in the Amazon region, belonging to the family Arecaceae and compassing approximately 200 genera and about 2600 species, distributed predominantly in tropical and subtropical areas [1], a by-product is produced and/or discharged, the açaí seeds, posing a huge environmental problem of solid waste management in Belém metropolitan

The State of Pará is the largest national producer of açaí with 1,012,740 ton/year of fruits [2], being the production due to extractive 198,149 tons/year of fruits in the crop year 2014 [3], representing 55.4% (wt.) of the national production of extractive açaí in the crop year 2014, and the production due to agricultural systems using a planted area of 154,500 hectare, was 814,590 tons in the year 2014. Of the total 1,012,740 tons/year of fruits, 8,405,742

The metropolitan region of Belém-Pará-Brazil, capital the State of Pará, has approximately 10,000 stores of açaí commercialization, producing an average of 200 kg açaí seeds/day per store, thus producing around 2000 tons residue/day [4]. In 2015, there was a growth of 27.35% (wt.) in production, 10.86% (wt.) in planted area and 14.88% (wt.) on the specific production yield, compared to 2014 [2]. The seed of açaí is an oil-fiber seed, and according to the literature, constituted by a small solid endosperm attached to a tegument, rich in cellulose with approximately 53.20% (wt.), hemicelluloses 12.26% (wt.), lignin 22.30% (wt.), as well as 3.50% lipids (wt.) [5–9]. In a scenery, the modern industrial society focuses on minimization of global warming and

 emission, as well as energy efficient supply systems and less consumption of fossil-based fuels. To achieve this, the use of renewable energy resources is essential [10]. In this context, processes that minimize the industrial and agro-industrial residues either by reusing or recycling them result in energetic and environmental benefits to the global society. In addition, recycling industrial and agro-industrial residues enables to use raw materials of low cost,

Among the most important renewable energy sources, this biomass is considered as an important one, since it could be a suitable alternative for conventional fossil fuels [12]. In addition, biomass energy producing systems may be implemented not only close to industrial and agro-industrial production systems, but also in any location where vegetable species can be grown and/or domestic animals are reared [12]. The systematic use of biomass makes it possible to reduce global warming compared to fossil fuel energy systems, as all the veg-

is released when the plant material is burned and/or decays [12, 13]. Thus, by replanting the

species, as in the carbonization processes (e.g., pyrolysis), and hence contributing to close the

The residual açaí seeds, an oil-fiber seed rich lignin-cellulose material, whose centesimal composition reported in the literature is constituted of lipids between 1.65 and 3.56% (wt.), total fibers between 29.69 and 62.75% (wt.), hemicellulose between 9.01 and 14.19% (wt.), cellulose

for the photosynthesis process [13]. CO<sup>2</sup>

stored in the plant

produced by burning vegetable

making it possible to increase the economic viability of biofuels' production [11].

region, as well as in the municipalities around the city of Belém-Pará-Brazil.

tons/year is a residue (açaí seeds) representing approximately 83% (wt.).

The seeds of Açaí (*Euterpe oleracea*, Mart) obtained in a small Store of Açaí Commercialization, located in the District of Guamã, Belém-Pará-Brazil. **Figure 1** shows the anatomy of aça *<sup>i</sup>* ́ fruits (cross section): (1) Embryo, (2) Endocarp, (3) Scar, (4) Pulp, (5) Pericarp + Tegument, and (6) Mesocarp.

#### **2.2. Pre-treatment of açaí (***Euterpe oleracea***, Mart) seeds**

The seeds of Açaí (*Euterpe oleracea*, Mart) are submitted to drying at 105°C using a pilot oven with air recirculation (SOC, FABBE, Ltd, Brazil, Model: 170) for a period of 24 h. Afterward,

**Figure 1.** Anatomy of Açaí (*Euterpe oleracea*, Mart) fruit *in nature* (cross section): (1) embryo, (2) endocarp, (3) scar, (4) pulp, (5) pericarp + tegument, and (6) mesocarp.

the dried seeds are grinded using a laboratory knife cutting mill (TRAPP, Brazil, Model: TRF 600). Then, the dried and grinded açaí seeds are sieved using an 18 Mesh sieve to remove the excess fiber material.

#### *2.2.1. Centesimal and elemental characterization of açaí (Euterpe oleracea, Mart) seeds*

The centesimal and elemental characterizations of açaí (*Euterpe oleracea*, Mart) seeds are performed for moisture (AOAC 935.29), volatile matter (ASTM D 3175-07), ash (ASTM D 3174-04), fixed carbon (ASTM D6316-09), lipids (AOAC 963.15), proteins (AOAC 991.20), fibers according to the official methods reported in the literature [29], and insoluble lignin according to the method of Klason described elsewhere [30].

fractions (gasoline, kerosene, and light diesel-like fuels) is recorded and weighed. The distillation fractions are submitted to the pre-treatment of decantation to separate the aqueous and

**Figure 2.** Vigreux borosilicate-glass distillation column of 500 ml, electrical heating mantel, cryostat bath, Liebig

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

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

65

Bio-oil and the distillation fractions are obtained according to the boiling temperature range of fossil fuels (gasoline, kerosene, and diesel) physicochemical characterized for acid value (AOCS Cd 3d-63), density (ASTM D4052) at 25°C, kinematic viscosity (ASTM D445/D446), and refractive index (AOCS Cc 7-25), as described in the literature [31]. The qualitative analyses of chemical functions present in the bio-oil are performed by FT-IR spectroscopy, accord-

The separation and identification of all the compounds present in bio-oil are performed by GC-MS, using a gas chromatograph (Agilent Technologies, USA, Model: GC-7890B) coupled to MS-5977A Mass Spectrometer, a SLBTM-5 ms (30 m × 0.25 mm × 0.25 mm) fused silica capillary column. The temperature conditions used in the GC-MS were: injector temperature: 250°C; split: 1:50, detector temperature: 230°C and quadrupole: 150°C; injection volume: 1.0 mL; oven: 60°C/1 min; 3°C/min; 200°C/2 min; 20°C/min; 230°C/10 min. The intensity,

**2.4. Physicochemical analysis of bio-oil and distillation fractions and chemical** 

*2.4.1. Physicochemical analysis of bio-oil and distillation fractions*

organic phases.

**composition of bio-oil**

condenser, and separating funnel.

ing to the literature [31].

*2.4.2. GC-MS of bio-oil*

#### **2.3. Fractional distillation of bio-oil**

#### *2.3.1. Distillation: experimental apparatus and procedures*

The fractional distillation of bio-oil is performed by using an experimental apparatus, as described in the literature [31]. The distillation apparatus, illustrated in **Figure 2**, has an electrical heating blanket of 480 W (Fisaton, Model: 202E, Class: 300), which is thermostatically controlled, a 500 ml round bottom, and two neck flasks with outer joints. The side joint is used to insert a long-thin thermocouple of a digital thermometer, and the center joint is connected to a distillation column (Vigreux) of 30 cm. The center top-outer joint is connected to the bottom inner joint of a Liebig glass-borosilicate condenser. The Liebig glass-borosilicate condenser is connected to a 250 ml glass separator funnel by the top-outer joint. A thermocouple connected to the top-outer joint 24/40 of the distillation column makes it possible to measure the vapor temperature at the top of the borosilicate-glass distillation columns (Vigreux). A cryostat bath provides cold water at 15°C to the Liebig glass-borosilicate condenser. The 500-ml round-bottom borosilicate-glass flask and the distillation column are insulated with glass wool and aluminum foil sheet to avoid heat losses, respectively. The mass of distillation Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (*Euterpe oleracea*) Seeds http://dx.doi.org/10.5772/intechopen.79546 65

**Figure 2.** Vigreux borosilicate-glass distillation column of 500 ml, electrical heating mantel, cryostat bath, Liebig condenser, and separating funnel.

fractions (gasoline, kerosene, and light diesel-like fuels) is recorded and weighed. The distillation fractions are submitted to the pre-treatment of decantation to separate the aqueous and organic phases.

### **2.4. Physicochemical analysis of bio-oil and distillation fractions and chemical composition of bio-oil**

#### *2.4.1. Physicochemical analysis of bio-oil and distillation fractions*

Bio-oil and the distillation fractions are obtained according to the boiling temperature range of fossil fuels (gasoline, kerosene, and diesel) physicochemical characterized for acid value (AOCS Cd 3d-63), density (ASTM D4052) at 25°C, kinematic viscosity (ASTM D445/D446), and refractive index (AOCS Cc 7-25), as described in the literature [31]. The qualitative analyses of chemical functions present in the bio-oil are performed by FT-IR spectroscopy, according to the literature [31].

#### *2.4.2. GC-MS of bio-oil*

the dried seeds are grinded using a laboratory knife cutting mill (TRAPP, Brazil, Model: TRF 600). Then, the dried and grinded açaí seeds are sieved using an 18 Mesh sieve to remove the

**Figure 1.** Anatomy of Açaí (*Euterpe oleracea*, Mart) fruit *in nature* (cross section): (1) embryo, (2) endocarp, (3) scar, (4)

The centesimal and elemental characterizations of açaí (*Euterpe oleracea*, Mart) seeds are performed for moisture (AOAC 935.29), volatile matter (ASTM D 3175-07), ash (ASTM D 3174-04), fixed carbon (ASTM D6316-09), lipids (AOAC 963.15), proteins (AOAC 991.20), fibers according to the official methods reported in the literature [29], and insoluble lignin according to the

The fractional distillation of bio-oil is performed by using an experimental apparatus, as described in the literature [31]. The distillation apparatus, illustrated in **Figure 2**, has an electrical heating blanket of 480 W (Fisaton, Model: 202E, Class: 300), which is thermostatically controlled, a 500 ml round bottom, and two neck flasks with outer joints. The side joint is used to insert a long-thin thermocouple of a digital thermometer, and the center joint is connected to a distillation column (Vigreux) of 30 cm. The center top-outer joint is connected to the bottom inner joint of a Liebig glass-borosilicate condenser. The Liebig glass-borosilicate condenser is connected to a 250 ml glass separator funnel by the top-outer joint. A thermocouple connected to the top-outer joint 24/40 of the distillation column makes it possible to measure the vapor temperature at the top of the borosilicate-glass distillation columns (Vigreux). A cryostat bath provides cold water at 15°C to the Liebig glass-borosilicate condenser. The 500-ml round-bottom borosilicate-glass flask and the distillation column are insulated with glass wool and aluminum foil sheet to avoid heat losses, respectively. The mass of distillation

*2.2.1. Centesimal and elemental characterization of açaí (Euterpe oleracea, Mart) seeds*

excess fiber material.

64 Fractionation

method of Klason described elsewhere [30].

*2.3.1. Distillation: experimental apparatus and procedures*

**2.3. Fractional distillation of bio-oil**

pulp, (5) pericarp + tegument, and (6) mesocarp.

The separation and identification of all the compounds present in bio-oil are performed by GC-MS, using a gas chromatograph (Agilent Technologies, USA, Model: GC-7890B) coupled to MS-5977A Mass Spectrometer, a SLBTM-5 ms (30 m × 0.25 mm × 0.25 mm) fused silica capillary column. The temperature conditions used in the GC-MS were: injector temperature: 250°C; split: 1:50, detector temperature: 230°C and quadrupole: 150°C; injection volume: 1.0 mL; oven: 60°C/1 min; 3°C/min; 200°C/2 min; 20°C/min; 230°C/10 min. The intensity, 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 chemical composition of each experiment was estimated.

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

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].
