12.4 Review of Literature
French and Czernik (2010) assessed a series of commercial and laboratorysynthesised catalysts via the pyrolysis/catalytic cracking route for their hydrocarbon
production performance. For the production of stationary energy using boilers or
turbines, rapid pyrolysis bio-oils currently produced in demonstration and semicommercial facilities can be used as fuel, but they must be appreciably modified to
become sustainable transport fuel. To remove oxygen from organic compounds and
transform into hydrocarbons by catalytic upgrading of pyrolysis vapours with zeolite
is a favourable method. Cellulose, lignin and wood were the types of raw materials
used. Batch experiments were conducted in which raw materials, quartz boats and
the catalysts pyrolysed at a temperature between 400 and 600
C. The ratio of
catalyst to biomass ratio of 5:10 (by weight) was used. Molecular beam mass
spectrometry (MBMS) was used to analyse the product for vapour and gas composition. The total highest hydrocarbon yield of 16 wt%, of which 3.5 wt% is toluene,
was attained with ZSM-5 substituted with nickel, cobalt, iron and gallium. Tests
conducted in a semi-continuous flow reactor reported changes in the composition of
the volatile products produced by pyrolysis/steam cracking with respect to time. The
deoxygenation activity decreases over time due to the coke deposits formed on the
catalyst.
Zhang et al. (2005) pyrolysed a biomass in a fluidised-bed unit (5 kg/h) to
maximise the liquid yield. The liquid product formed during pyrolysis was separated
into aqueous and oil phases, respectively. The oil phase reinforced by a sulphide
catalyst of Co-Mo-P in an autoclave. The optimum conditions were determined by
studying the effects of reaction conditions on product distribution. The comparison
was made by analysis between the crude oil phase and the improved liquid fuel. The
former was soluble in methanol, while the latter was soluble in oil.
Czernik et al. (2007) proposed a two-step process, rapid pyrolysis of biomass,
which produces high yields of a liquid product, the bio-oil, followed by catalytic
steam reforming of the bio-oil to produce biomass, hydrogen. Thermoconversion of
biomass is one of the most important short-term options for the production of
renewable hydrogen and can supply an important part of the transport fuel needed
in the future. A big advantage of this concept is that bio-oil is much easier and
cheaper to transport than biomass or hydrogen. As a result, biomass processing and
hydrogen production can be carried out at different locations, optimised for the
supply of raw materials and the infrastructure for the distribution of hydrogen. This
approach makes the process very suitable for centralised and distributed hydrogen
production. This work demonstrates the reforming of bio-oil in a fluidised-bed
system at scale and provides the hydrogen yield obtained using various commercial
and tailor-made catalysts.
Aho et al. (2008) carried out catalytic pyrolysis in a fluid bed reactor at 450
C
using pine biomass and zeolite acid catalyst structures which are used as the bed
material in the reactor. In non-catalytic pyrolysis, quartz sand was used as reference
material, while in pine pyrolysis, the proton forms of Beta-, Y-, ZSM-5 and
modernite were tested as catalysts. The pyrolysis product phase yield is slightly
336
S. Aswin et al.
French and Czernik (2010) assessed a series of commercial and laboratorysynthesised catalysts via the pyrolysis/catalytic cracking route for their hydrocarbon
production performance. For the production of stationary energy using boilers or
turbines, rapid pyrolysis bio-oils currently produced in demonstration and semicommercial facilities can be used as fuel, but they must be appreciably modified to
become sustainable transport fuel. To remove oxygen from organic compounds and
transform into hydrocarbons by catalytic upgrading of pyrolysis vapours with zeolite
is a favourable method. Cellulose, lignin and wood were the types of raw materials
used. Batch experiments were conducted in which raw materials, quartz boats and
the catalysts pyrolysed at a temperature between 400 and 600
C. The ratio of
catalyst to biomass ratio of 5:10 (by weight) was used. Molecular beam mass
spectrometry (MBMS) was used to analyse the product for vapour and gas composition. The total highest hydrocarbon yield of 16 wt%, of which 3.5 wt% is toluene,
was attained with ZSM-5 substituted with nickel, cobalt, iron and gallium. Tests
conducted in a semi-continuous flow reactor reported changes in the composition of
the volatile products produced by pyrolysis/steam cracking with respect to time. The
deoxygenation activity decreases over time due to the coke deposits formed on the
catalyst.
Zhang et al. (2005) pyrolysed a biomass in a fluidised-bed unit (5 kg/h) to
maximise the liquid yield. The liquid product formed during pyrolysis was separated
into aqueous and oil phases, respectively. The oil phase reinforced by a sulphide
catalyst of Co-Mo-P in an autoclave. The optimum conditions were determined by
studying the effects of reaction conditions on product distribution. The comparison
was made by analysis between the crude oil phase and the improved liquid fuel. The
former was soluble in methanol, while the latter was soluble in oil.
Czernik et al. (2007) proposed a two-step process, rapid pyrolysis of biomass,
which produces high yields of a liquid product, the bio-oil, followed by catalytic
steam reforming of the bio-oil to produce biomass, hydrogen. Thermoconversion of
biomass is one of the most important short-term options for the production of
renewable hydrogen and can supply an important part of the transport fuel needed
in the future. A big advantage of this concept is that bio-oil is much easier and
cheaper to transport than biomass or hydrogen. As a result, biomass processing and
hydrogen production can be carried out at different locations, optimised for the
supply of raw materials and the infrastructure for the distribution of hydrogen. This
approach makes the process very suitable for centralised and distributed hydrogen
production. This work demonstrates the reforming of bio-oil in a fluidised-bed
system at scale and provides the hydrogen yield obtained using various commercial
and tailor-made catalysts.
Aho et al. (2008) carried out catalytic pyrolysis in a fluid bed reactor at 450
C
using pine biomass and zeolite acid catalyst structures which are used as the bed
material in the reactor. In non-catalytic pyrolysis, quartz sand was used as reference
material, while in pine pyrolysis, the proton forms of Beta-, Y-, ZSM-5 and
modernite were tested as catalysts. The pyrolysis product phase yield is slightly
336
S. Aswin et al.