11
Introduction
illustrates that coal–water chemistry still needs to be further explored, particularly
under high-temperature and high-pressure conditions.
1.2.5 ChAPTer 6: ProduCTion oF SynTheTiC FuelS
By AqueouS-PhASe reForming
Along with the hydrothermal conversion of biomass, an aqueous-phase reforming in
subcritical water also plays an important role in the production of synfuels from a
variety of oxygenated compounds in biomass. An aqueous-phase reforming process
carries out selective conversion of sugar-based reactants such as glucose and fructose
to hydrogen, syngas, or liquid alkanes and monofunctional groups depending on the
nature of catalysts and other operating conditions. These compounds can be subsequently upgraded to liquid fuels using a variety of conventional refining operations.
The use of an aqueous-phase reforming process using a suitable catalyst to generate selective fuel products from various organic compounds is a relatively new
and exciting technology. In this process, both catalytic materials and the nature of
support are equally important. Chapter 6 gives a detailed and up-to-date account of
the use of selective catalysis for the production of a variety of synfuels and/or useful
platform chemicals in an aqueous-phase environment.
In the recent years, significant development work has been carried out to produce
liquid fuels by upgrading (through a variety of condensation reactions) of monofunctional groups produced by aqueous-phase reforming process. This has led to
the development of a “bioforming process” by Virent Inc., Madison, Wisconsin. The
process is highly energy efficient and produces selective hydrocarbons that can be
useful for specialized jet fuel, diesel, and other transportation fuel materials. The
chapter outlines our present state of knowledge of this important and novel use of
water chemistry to produce hydrogen and selective liquid transportation fuels.
1.2.6 ChAPTer 7: ProduCTion oF SynTheTiC FuelS And ChemiCAlS By
hydrolySiS FolloWed By SeleCTive CATAlyTiC ConverSionS
Chapter 7 deals with another method of producing liquid fuels, fuel additives, and
chemicals from a variety of feedstock using water. The method involves acid hydrolysis of a variety of carbohydrates, cellulose waste, and biomass to produce important
platform chemicals such as furfural, levulinic acid (LA), and gamma-valerolactone
(GVL). These chemicals can be catalytically upgraded to produce a variety of fuels,
fuel additives, and useful chemicals.
The chapter describes the “biofine hydrolysis process,” which fractionates lignocellulose into various fractions such as cellulose, hemicellulose, and lignin by hydrolysis
and produces six-carbon (glucose) and five-carbon sugars (xylose). Instead of reforming these oxygenated compounds, as described in Chapter 6, five- and six-carbon
sugars are catalytically converted to intermediate platform chemicals such as furfuryl
and hydroxymethylfurfuryl (HMF) for five-carbon sugars and LA for six-carbon sugars. LA can also be further converted to GVL, another important platform chemical
that can also be converted to a number of fuels, fuel additives, and chemicals. Formic
acid and ligneous char are produced as byproducts for the biofine hydrolysis process.
Introduction
illustrates that coal–water chemistry still needs to be further explored, particularly
under high-temperature and high-pressure conditions.
1.2.5 ChAPTer 6: ProduCTion oF SynTheTiC FuelS
By AqueouS-PhASe reForming
Along with the hydrothermal conversion of biomass, an aqueous-phase reforming in
subcritical water also plays an important role in the production of synfuels from a
variety of oxygenated compounds in biomass. An aqueous-phase reforming process
carries out selective conversion of sugar-based reactants such as glucose and fructose
to hydrogen, syngas, or liquid alkanes and monofunctional groups depending on the
nature of catalysts and other operating conditions. These compounds can be subsequently upgraded to liquid fuels using a variety of conventional refining operations.
The use of an aqueous-phase reforming process using a suitable catalyst to generate selective fuel products from various organic compounds is a relatively new
and exciting technology. In this process, both catalytic materials and the nature of
support are equally important. Chapter 6 gives a detailed and up-to-date account of
the use of selective catalysis for the production of a variety of synfuels and/or useful
platform chemicals in an aqueous-phase environment.
In the recent years, significant development work has been carried out to produce
liquid fuels by upgrading (through a variety of condensation reactions) of monofunctional groups produced by aqueous-phase reforming process. This has led to
the development of a “bioforming process” by Virent Inc., Madison, Wisconsin. The
process is highly energy efficient and produces selective hydrocarbons that can be
useful for specialized jet fuel, diesel, and other transportation fuel materials. The
chapter outlines our present state of knowledge of this important and novel use of
water chemistry to produce hydrogen and selective liquid transportation fuels.
1.2.6 ChAPTer 7: ProduCTion oF SynTheTiC FuelS And ChemiCAlS By
hydrolySiS FolloWed By SeleCTive CATAlyTiC ConverSionS
Chapter 7 deals with another method of producing liquid fuels, fuel additives, and
chemicals from a variety of feedstock using water. The method involves acid hydrolysis of a variety of carbohydrates, cellulose waste, and biomass to produce important
platform chemicals such as furfural, levulinic acid (LA), and gamma-valerolactone
(GVL). These chemicals can be catalytically upgraded to produce a variety of fuels,
fuel additives, and useful chemicals.
The chapter describes the “biofine hydrolysis process,” which fractionates lignocellulose into various fractions such as cellulose, hemicellulose, and lignin by hydrolysis
and produces six-carbon (glucose) and five-carbon sugars (xylose). Instead of reforming these oxygenated compounds, as described in Chapter 6, five- and six-carbon
sugars are catalytically converted to intermediate platform chemicals such as furfuryl
and hydroxymethylfurfuryl (HMF) for five-carbon sugars and LA for six-carbon sugars. LA can also be further converted to GVL, another important platform chemical
that can also be converted to a number of fuels, fuel additives, and chemicals. Formic
acid and ligneous char are produced as byproducts for the biofine hydrolysis process.