2.9
Biomass Conversion Processes
As mentioned earlier, nowadays the renewable biomass is considered a real source to
obtain many types of products like fuels (bioethanol, biodiesel, biohydrogen,
biobutanol, biomethane, etc.) and platform chemicals (organic acids, monomers,
etc.) (Müller-Langer and Kaltschmitt 2015; Du Preez 2016), which have been
included inside civilization needs, taking into account the humanity sustainable
development (Solomon et al. 2015). Thus, in this part, what kind of fuels and
chemicals are obtained from renewable resources and the principal and current
processes used to goal the conversions will be discussed.
2.10 Fuels and Chemicals from Lignocellulosic Biomass
At present day, the society has basic needs of food, clothes, fuels, and other
chemicals, which are dependent principally on oil, natural gas, and coal. Among
them, the oil is the number one precursor for different industries, which has
generated a lot of direct negative alterations to natural ecosystems and adverse
effects to the human health, mainly by green gas emissions. Therefore, to replace
fossil-based products by bio-based products is an attractive issue in the current world
(De Bhowmick et al. 2018).
Taking specifically about agricultural waste biomass, lignocellulosic raw material
has been studied with the aim to produce different chemicals, since this material is
considered clean, renewable, abundant, and available. However, these lignocellulosic biomass must be conditioned through pretreatment and hydrolysis processes in
order to generate an unstructured material, thus allowing cellulose, hemicelluloses,
and lignin to be more exposed and to obtain simpler molecules (De Bhowmick et al.
2018). To simply explain the difference between pretreatment and hydrolysis, it
could imagine a wool scarf, when it is submitted to stretch, the wood fibers are more
visible (pretreatment), and when these stretched fibers are cut with scissors, the wool
fibers will be broken into smaller pieces (hydrolysis). In general, pretreatments are
processes applied to lignocellulosic biomass to promote access to cellulose,
hemicelluloses, and removal or modification of lignin, and hydrolysis is a process
to break cellulose and hemicelluloses into smaller molecules (Kumar et al. 2018).
Both processes (pretreatment and hydrolysis) are used to obtain other bio-based
products known like platform chemicals or intermediate products (Du Preez 2016;
Yung 2016). Furfural, hydroxymethylfurfural, levulinic acid, furfuryl alcohol, sorbitol and others are examples of bio-based products different to biofuels (Iroegbu
and Hlangothi 2018; Steinbach et al. 2017; Hartono et al. 2016).
2 Biofuels Generation Based on Technical Process and Biomass Quality
53
Biomass Conversion Processes
As mentioned earlier, nowadays the renewable biomass is considered a real source to
obtain many types of products like fuels (bioethanol, biodiesel, biohydrogen,
biobutanol, biomethane, etc.) and platform chemicals (organic acids, monomers,
etc.) (Müller-Langer and Kaltschmitt 2015; Du Preez 2016), which have been
included inside civilization needs, taking into account the humanity sustainable
development (Solomon et al. 2015). Thus, in this part, what kind of fuels and
chemicals are obtained from renewable resources and the principal and current
processes used to goal the conversions will be discussed.
2.10 Fuels and Chemicals from Lignocellulosic Biomass
At present day, the society has basic needs of food, clothes, fuels, and other
chemicals, which are dependent principally on oil, natural gas, and coal. Among
them, the oil is the number one precursor for different industries, which has
generated a lot of direct negative alterations to natural ecosystems and adverse
effects to the human health, mainly by green gas emissions. Therefore, to replace
fossil-based products by bio-based products is an attractive issue in the current world
(De Bhowmick et al. 2018).
Taking specifically about agricultural waste biomass, lignocellulosic raw material
has been studied with the aim to produce different chemicals, since this material is
considered clean, renewable, abundant, and available. However, these lignocellulosic biomass must be conditioned through pretreatment and hydrolysis processes in
order to generate an unstructured material, thus allowing cellulose, hemicelluloses,
and lignin to be more exposed and to obtain simpler molecules (De Bhowmick et al.
2018). To simply explain the difference between pretreatment and hydrolysis, it
could imagine a wool scarf, when it is submitted to stretch, the wood fibers are more
visible (pretreatment), and when these stretched fibers are cut with scissors, the wool
fibers will be broken into smaller pieces (hydrolysis). In general, pretreatments are
processes applied to lignocellulosic biomass to promote access to cellulose,
hemicelluloses, and removal or modification of lignin, and hydrolysis is a process
to break cellulose and hemicelluloses into smaller molecules (Kumar et al. 2018).
Both processes (pretreatment and hydrolysis) are used to obtain other bio-based
products known like platform chemicals or intermediate products (Du Preez 2016;
Yung 2016). Furfural, hydroxymethylfurfural, levulinic acid, furfuryl alcohol, sorbitol and others are examples of bio-based products different to biofuels (Iroegbu
and Hlangothi 2018; Steinbach et al. 2017; Hartono et al. 2016).
2 Biofuels Generation Based on Technical Process and Biomass Quality
53