34
Lignocellulosic materials are commonly composed of lignin (10–25%), hemicellulose (20–40%) and cellulose (40–60%). Hemicellulose biomass is getting more
appreciation because of its high xylan content. This xylan content is mainly formed
by xylose which is an interesting chemical in the biofuel industry [244]. According
to the previous section, furfural can be obtained using lignocellulosic feedstocks
containing a high level of xylose. Furfural has an annual production of 250,000
tonnes, and the present method to extract this chemical compound from xylose
sources is the acid-catalysed dehydration [245]. Oat hulls (OHS) and sugarcane
bagasse (SB) have been recognized as one of the most promising xylose-rich biomass for furfural production [220].
Presently, oat is one of the main produced cereals around the world, and its hull,
which is a residue from the process of oat milling, has a high potential as a renewable biomass source because of its availability. OHS is a suitable feedstock to produce gaseous and liquid fuels through advanced thermochemical processes
(gasification and pyrolysis) [246].
OHS is generally formed from lignin (17–20%), hemicellulose (32–35%) and
cellulose (35–45%) [247]. OHS has a low ash content (4.5–5.5%), and also it does
not require to be milled when treated because of its particle size and homogenous
morphological structure [247]. Due to the high amount of hemicellulose, oat hulls
are a good source of furfural and xylose (pentose sugars) [248]. However, some
kinetic parameters of oat hulls need to be understood to develop this process [246].
Nowadays, OHS is mostly used to produce energy from combustion because of
its HHV (16 MJ/kg) [249]. This residue shows a practical nutritive value and is
applied in the human and animal food industry [246]. Furthermore, it is reported
that OHS can be used for ethanol production through chemical hydrolysis [247].
Therefore, OHS can be considered as a renewable resource for biofuel production
due to its potential and availability [249].
Sugarcane is the most prominent farming harvest in the world. Bagasse can be
obtained from sugarcane milling to extract its juice for production of sugar or ethanol, which is the main residue of sugarcane [250]. The raw SB is made in many
countries, and its production is more significant and efficient in sub-tropical and
tropical climates [251]. Brazil and India are the leading SB producers in the world,
and this industry represents a relevant role for the energy needs in developing countries [252]. Normally, 1000 kg of fresh sugarcane can generate 280 kg of dry
bagasse, 110 kg of sugar and 45 kg of molasses [250]. For ethanol production, cane
straw and bagasse residues represent around 35% of the total sugarcane weight [253].
SB has a lamella structure, and it is formed from lignin (20–25%), hemicellulose
(20–30%), cellulose (40–50%) and low ash content (1.5–3%) [250]. Presently, more
than 500 sugarcane species are cultivated in Brazil, and 20 new species have been
created every single year [253]. However, the chemical compositions of the different SB species do not diverge significantly from the main compounds [253]. The
cellulose elements of SB have crystalline and amorphous structures that require to
be submitted to thermochemical and physical treatments to reach to the polysaccharides components [252]. In order to increase the SB particle surface area, milling
is a suitable physical approach. Thermochemical treatments are ammonia, alkaline
H. Jahangiri et al.
Lignocellulosic materials are commonly composed of lignin (10–25%), hemicellulose (20–40%) and cellulose (40–60%). Hemicellulose biomass is getting more
appreciation because of its high xylan content. This xylan content is mainly formed
by xylose which is an interesting chemical in the biofuel industry [244]. According
to the previous section, furfural can be obtained using lignocellulosic feedstocks
containing a high level of xylose. Furfural has an annual production of 250,000
tonnes, and the present method to extract this chemical compound from xylose
sources is the acid-catalysed dehydration [245]. Oat hulls (OHS) and sugarcane
bagasse (SB) have been recognized as one of the most promising xylose-rich biomass for furfural production [220].
Presently, oat is one of the main produced cereals around the world, and its hull,
which is a residue from the process of oat milling, has a high potential as a renewable biomass source because of its availability. OHS is a suitable feedstock to produce gaseous and liquid fuels through advanced thermochemical processes
(gasification and pyrolysis) [246].
OHS is generally formed from lignin (17–20%), hemicellulose (32–35%) and
cellulose (35–45%) [247]. OHS has a low ash content (4.5–5.5%), and also it does
not require to be milled when treated because of its particle size and homogenous
morphological structure [247]. Due to the high amount of hemicellulose, oat hulls
are a good source of furfural and xylose (pentose sugars) [248]. However, some
kinetic parameters of oat hulls need to be understood to develop this process [246].
Nowadays, OHS is mostly used to produce energy from combustion because of
its HHV (16 MJ/kg) [249]. This residue shows a practical nutritive value and is
applied in the human and animal food industry [246]. Furthermore, it is reported
that OHS can be used for ethanol production through chemical hydrolysis [247].
Therefore, OHS can be considered as a renewable resource for biofuel production
due to its potential and availability [249].
Sugarcane is the most prominent farming harvest in the world. Bagasse can be
obtained from sugarcane milling to extract its juice for production of sugar or ethanol, which is the main residue of sugarcane [250]. The raw SB is made in many
countries, and its production is more significant and efficient in sub-tropical and
tropical climates [251]. Brazil and India are the leading SB producers in the world,
and this industry represents a relevant role for the energy needs in developing countries [252]. Normally, 1000 kg of fresh sugarcane can generate 280 kg of dry
bagasse, 110 kg of sugar and 45 kg of molasses [250]. For ethanol production, cane
straw and bagasse residues represent around 35% of the total sugarcane weight [253].
SB has a lamella structure, and it is formed from lignin (20–25%), hemicellulose
(20–30%), cellulose (40–50%) and low ash content (1.5–3%) [250]. Presently, more
than 500 sugarcane species are cultivated in Brazil, and 20 new species have been
created every single year [253]. However, the chemical compositions of the different SB species do not diverge significantly from the main compounds [253]. The
cellulose elements of SB have crystalline and amorphous structures that require to
be submitted to thermochemical and physical treatments to reach to the polysaccharides components [252]. In order to increase the SB particle surface area, milling
is a suitable physical approach. Thermochemical treatments are ammonia, alkaline
H. Jahangiri et al.