558
Utilization of crude glycerol as biochemical feedstock for 1,3-PDO has brought
into focus the production of several other important chemicals/chemical intermediates through enzymatic processes. Microbial processes with crude glycerol as feedstock have been reported for the production of hydrogen, methanol, ethanol,
n-butanol, glyceric acid, citric acid, polyunsaturated fatty acids, lactic acid, succinic
acid and biopolymers like poly hydroxy alkanoate (PHA), poly hydroxy butyrate
(PHB) and acrylates. Development of microbial processes for these chemicals,
types of microorganisms employed and the process conditions adopted have been
covered in detail in the reviews by Dobson et al. [355] and Garlapati et al. [356].
Oligomerization of glycerol to polyglycerol and conversion to olefins (ethylene,
propylene and butadiene) are the other processes that utilize glycerol as raw material [322].
Though a number of processes have been developed and patented [322] for the
conversion of glycerol to value-added chemicals, fuels and fuel additives, only few
of them have reached commercial scale. Epichlorohydrin from glycerol (Dow,
Solvay) via dichloro propanol [21], 1,3-PDO using recombinant Escherichia coli
(DuPont) and polyglycerols by Sakamato Japan have been successful on commercial scale. Tremendous opportunities as well as challenges remain in glycerol conversion processes, requiring continuous research efforts to improve process
efficiency, selectivity, catalyst stability and reduction in the cost of production, to
enable viability on commercial scale.
8 Conversion of Furfuryl Alcohol into Fuels and Chemicals
Furfuryl alcohol (FOL) is one amongst the most important derivatives of furfural
(FAL), another abundant biomass intermediate and a versatile platform chemical
[357]. More than 65% of FAL is utilized for the manufacture of FOL by catalytic
hydrogenation, which has been studied extensively [357, 358]. Major applications
of FOL derivatives towards production of value-added chemicals/fuels are illustrated in Fig. 31.
An important derivative of FOL is levulinic acid (LA, 4-oxopentanoic acid),
which is one amongst the 12 platform chemicals identified by US DOE in 2004,
with tremendous application potential. Global market for LA during the period
2019–2024 is projected to grow at CAGR of 4.9%, to touch US$ 34.5 Mill. by 2024
[359]. As many as 16 different application segments for LA have been listed by
Bozell et al. [360]. LA can be produced from lignocellulosic biomass via the Biofine
process [361] and also from FOL by acid-catalysed ring opening in H 2 O [362]. LA
with two active functional groups (keto and carboxyl) undergoes a range of chemical transformations (Fig. 32) yielding highly useful chemicals and fuels. Salient
features of these transformations brought out by different catalysts have been covered in the reviews by Bozell et al. [360], Mariscal et al. [357] and Xue et al. [363].
Delta-aminolevulinic acid (DALA), another derivative of LA, is useful as biodegradable broad-spectrum herbicide/insecticide and for cancer treatment [360].
R. Vinayagamoorthi et al.
Utilization of crude glycerol as biochemical feedstock for 1,3-PDO has brought
into focus the production of several other important chemicals/chemical intermediates through enzymatic processes. Microbial processes with crude glycerol as feedstock have been reported for the production of hydrogen, methanol, ethanol,
n-butanol, glyceric acid, citric acid, polyunsaturated fatty acids, lactic acid, succinic
acid and biopolymers like poly hydroxy alkanoate (PHA), poly hydroxy butyrate
(PHB) and acrylates. Development of microbial processes for these chemicals,
types of microorganisms employed and the process conditions adopted have been
covered in detail in the reviews by Dobson et al. [355] and Garlapati et al. [356].
Oligomerization of glycerol to polyglycerol and conversion to olefins (ethylene,
propylene and butadiene) are the other processes that utilize glycerol as raw material [322].
Though a number of processes have been developed and patented [322] for the
conversion of glycerol to value-added chemicals, fuels and fuel additives, only few
of them have reached commercial scale. Epichlorohydrin from glycerol (Dow,
Solvay) via dichloro propanol [21], 1,3-PDO using recombinant Escherichia coli
(DuPont) and polyglycerols by Sakamato Japan have been successful on commercial scale. Tremendous opportunities as well as challenges remain in glycerol conversion processes, requiring continuous research efforts to improve process
efficiency, selectivity, catalyst stability and reduction in the cost of production, to
enable viability on commercial scale.
8 Conversion of Furfuryl Alcohol into Fuels and Chemicals
Furfuryl alcohol (FOL) is one amongst the most important derivatives of furfural
(FAL), another abundant biomass intermediate and a versatile platform chemical
[357]. More than 65% of FAL is utilized for the manufacture of FOL by catalytic
hydrogenation, which has been studied extensively [357, 358]. Major applications
of FOL derivatives towards production of value-added chemicals/fuels are illustrated in Fig. 31.
An important derivative of FOL is levulinic acid (LA, 4-oxopentanoic acid),
which is one amongst the 12 platform chemicals identified by US DOE in 2004,
with tremendous application potential. Global market for LA during the period
2019–2024 is projected to grow at CAGR of 4.9%, to touch US$ 34.5 Mill. by 2024
[359]. As many as 16 different application segments for LA have been listed by
Bozell et al. [360]. LA can be produced from lignocellulosic biomass via the Biofine
process [361] and also from FOL by acid-catalysed ring opening in H 2 O [362]. LA
with two active functional groups (keto and carboxyl) undergoes a range of chemical transformations (Fig. 32) yielding highly useful chemicals and fuels. Salient
features of these transformations brought out by different catalysts have been covered in the reviews by Bozell et al. [360], Mariscal et al. [357] and Xue et al. [363].
Delta-aminolevulinic acid (DALA), another derivative of LA, is useful as biodegradable broad-spectrum herbicide/insecticide and for cancer treatment [360].
R. Vinayagamoorthi et al.