347
lignocellulosic biomass as an important feedstock and raw material. To economically utilize biomass, we should not just aim for a single component but also the
other components present. Biomass, in general, is composed of mainly three components: cellulose, lignin, and hemicellulose [8, 9]. All these three components of
lignocellulose biomass have signification potential and approaching for one at a
time would waste two of the other active components.
The biochemical industry has constantly been driving a dedicated emphasis on
the production of some chemical intermediates that can prove to be the building
blocks for the subsequent design and synthesis of a family of end-user-centric
chemicals. These chemicals, called the “platform chemicals,” are the promising
candidates that can be transformed into commercially important chemicals. The US
Department of Energy (2004) report has made a remarkable amount of reference on
the identification of these promising bio-derived platform molecules and presented
the well-known list of 12 highly valued building blocks [10]. In their own words,
they defined these platform chemicals as follows: “Building block chemicals, as
considered for this analysis, are molecules with multiple functional groups that possess the potential to be transformed into new families of useful molecules.” Platform
chemicals have the potential to create high-value commercial products. However,
by merely being intermediaries, they will not add value to the industrial chain. That
value can actually be substantiated by transforming these intermediates into highvalue end products which can properly be adopted by the end users. Glucose monomers are end products of cellulose (biomass precursor) hydrolysis. And various
value-added compounds can be derived from this glucose and the end product
obtained based on the type of catalyst selected and reaction conditions adapted. Few
of them are sorbitol via hydrogenation reaction, gluconic acid via oxidation, fructose through isomerization, and 5-hydroxymethylfurfural (5-HMF). The latter can
be further converted into levulinic acid (LA) through hydration and formic acid
through hydrolysis [11].
LA is an important platform chemical produced from a biomass-based feedstock
for several petrochemical operations. An extensive literature is available on useful
properties and prospective industrial applications of LA and its derivatives [11–13].
2 Levulinic Acid: An Introduction
In the current scenario, LA is gaining considerable attention as it is sourced from
biomass and is an essential feedstock for the current petrochemical operations/processing. 4-Oxypentanoic acid, popularly known as levulinic acid, is one of the 12
platform organic chemicals that can be efficaciously derived from biomass and utilized for the economical production of biofuels [11]. The significance of LA is
mainly attributed to the presence of carboxylic acid and ketone functional groups in
them which can lead to various value-added adducts via several organic reactions.
On the molecular level, conversion of lignin-rich biomass to levulinic acid follows a complicated scheme of reactions involving several byproducts and
Solid Acid-Catalyzed Esterification of Levulinic Acid for Production of Value-Added…
lignocellulosic biomass as an important feedstock and raw material. To economically utilize biomass, we should not just aim for a single component but also the
other components present. Biomass, in general, is composed of mainly three components: cellulose, lignin, and hemicellulose [8, 9]. All these three components of
lignocellulose biomass have signification potential and approaching for one at a
time would waste two of the other active components.
The biochemical industry has constantly been driving a dedicated emphasis on
the production of some chemical intermediates that can prove to be the building
blocks for the subsequent design and synthesis of a family of end-user-centric
chemicals. These chemicals, called the “platform chemicals,” are the promising
candidates that can be transformed into commercially important chemicals. The US
Department of Energy (2004) report has made a remarkable amount of reference on
the identification of these promising bio-derived platform molecules and presented
the well-known list of 12 highly valued building blocks [10]. In their own words,
they defined these platform chemicals as follows: “Building block chemicals, as
considered for this analysis, are molecules with multiple functional groups that possess the potential to be transformed into new families of useful molecules.” Platform
chemicals have the potential to create high-value commercial products. However,
by merely being intermediaries, they will not add value to the industrial chain. That
value can actually be substantiated by transforming these intermediates into highvalue end products which can properly be adopted by the end users. Glucose monomers are end products of cellulose (biomass precursor) hydrolysis. And various
value-added compounds can be derived from this glucose and the end product
obtained based on the type of catalyst selected and reaction conditions adapted. Few
of them are sorbitol via hydrogenation reaction, gluconic acid via oxidation, fructose through isomerization, and 5-hydroxymethylfurfural (5-HMF). The latter can
be further converted into levulinic acid (LA) through hydration and formic acid
through hydrolysis [11].
LA is an important platform chemical produced from a biomass-based feedstock
for several petrochemical operations. An extensive literature is available on useful
properties and prospective industrial applications of LA and its derivatives [11–13].
2 Levulinic Acid: An Introduction
In the current scenario, LA is gaining considerable attention as it is sourced from
biomass and is an essential feedstock for the current petrochemical operations/processing. 4-Oxypentanoic acid, popularly known as levulinic acid, is one of the 12
platform organic chemicals that can be efficaciously derived from biomass and utilized for the economical production of biofuels [11]. The significance of LA is
mainly attributed to the presence of carboxylic acid and ketone functional groups in
them which can lead to various value-added adducts via several organic reactions.
On the molecular level, conversion of lignin-rich biomass to levulinic acid follows a complicated scheme of reactions involving several byproducts and
Solid Acid-Catalyzed Esterification of Levulinic Acid for Production of Value-Added…