5.1 Biomass Decomposition
53
fermentation have been reported which employ different nanomaterials of both inorganic and organic origins for the production of H 2 . For instance, nanomaterials of
different metal and metal oxides such as Cu, Au, Pd, Ag, and iron-iron-oxide. TiO 2
are involved in dark fermentation of the biomass for hydrogen generation [22]. The
current chapter is based on the applications of nanomaterials that are used in H 2
generation from biomass.
5.2 Thermochemical Conversion of Biomass
and Nanotechnology
Nanomaterials are commonly employed as catalysts in various thermochemical reactions for the generation of hydrogen from biomass, such as gasification, supercritical
water gas formation, and steam reforming. In a study, trimetallic Ni-La-Fe/γ-Al 2 O 3
nanomaterials were used for biomass gasification reaction. The nanomaterial was
prepared for the removal of tar in biomass steam gasification for the production of
improved quality gas. The said nanomaterials were prepared by deposition–precipitation (DP) method. For the preparation of the materials, γ-Al 2 O 3 substrate was
depressurized at few torr for 1 h. This was done for the removal of air from the pores
of the substrate. On the other hand, solution of Ni(NO 3 ) 2 .6H 2 O, La(NO 3 ) 3 .6HO,
Fe(NO 3 ) 3 .9H 2 O, and urea was made in distilled water and stirred at room temperature until a homogenized mixture is formed. Afterward, the mixture was transferred
on the γ-Al 2 O 3 substrate which was sealed in the glass vessel and heated in the oil
bath at 115 °C for 2.5 h. The product was obtained in the form of brown deposition
on the surface of the substrate. After the completion of the reaction, the product
was cooled at optimized conditions and washed with deionized (DI) water until
the colorless product was obtained. The colorless nanomaterials were first dried at
90 °C for 6 h and then calcined at 550 °C for 1 h. Scanning electron microscope
(SEM) and X-ray diffractometer (XRD) were used to determine radial cross section
of the disk and morphology. The particle size was analyzed with transmission electron microscopy (TEM) and the metal content was determined by energy-dispersive
spectroscopy (EDX). The catalyst activity of the prepared material was evaluated
by conducting the gasification experiment with saw dust (as the biomass) with and
without the nanocatalysts. When the catalysts were used, 99% removal of the tar and
10% volume increase in the generation of H 2 were observed [23].
In a study, biomass was used as the raw material for the production of biodiesel,
and crude glycerol was obtained as the significant by-product. Afterward, hydrogen
was produced from this crude glycerol in the presence Ni (OH) 2 decorated on TiO 2
nanotubes under sunlight. In the practice, the TiO 2 nanotubes were prepared first by
hydrothermal method, and later on they were deposited by Ni(OH) 2 quantum dots
via wet impregnation method. For this purpose, TiO 2 particles were dissolved in the
solution of NaOH and placed in the autoclave lined with Teflon at 130 °C for 20 h.
The white product thus obtained was washed with distilled water, dilute HCl, and
53
fermentation have been reported which employ different nanomaterials of both inorganic and organic origins for the production of H 2 . For instance, nanomaterials of
different metal and metal oxides such as Cu, Au, Pd, Ag, and iron-iron-oxide. TiO 2
are involved in dark fermentation of the biomass for hydrogen generation [22]. The
current chapter is based on the applications of nanomaterials that are used in H 2
generation from biomass.
5.2 Thermochemical Conversion of Biomass
and Nanotechnology
Nanomaterials are commonly employed as catalysts in various thermochemical reactions for the generation of hydrogen from biomass, such as gasification, supercritical
water gas formation, and steam reforming. In a study, trimetallic Ni-La-Fe/γ-Al 2 O 3
nanomaterials were used for biomass gasification reaction. The nanomaterial was
prepared for the removal of tar in biomass steam gasification for the production of
improved quality gas. The said nanomaterials were prepared by deposition–precipitation (DP) method. For the preparation of the materials, γ-Al 2 O 3 substrate was
depressurized at few torr for 1 h. This was done for the removal of air from the pores
of the substrate. On the other hand, solution of Ni(NO 3 ) 2 .6H 2 O, La(NO 3 ) 3 .6HO,
Fe(NO 3 ) 3 .9H 2 O, and urea was made in distilled water and stirred at room temperature until a homogenized mixture is formed. Afterward, the mixture was transferred
on the γ-Al 2 O 3 substrate which was sealed in the glass vessel and heated in the oil
bath at 115 °C for 2.5 h. The product was obtained in the form of brown deposition
on the surface of the substrate. After the completion of the reaction, the product
was cooled at optimized conditions and washed with deionized (DI) water until
the colorless product was obtained. The colorless nanomaterials were first dried at
90 °C for 6 h and then calcined at 550 °C for 1 h. Scanning electron microscope
(SEM) and X-ray diffractometer (XRD) were used to determine radial cross section
of the disk and morphology. The particle size was analyzed with transmission electron microscopy (TEM) and the metal content was determined by energy-dispersive
spectroscopy (EDX). The catalyst activity of the prepared material was evaluated
by conducting the gasification experiment with saw dust (as the biomass) with and
without the nanocatalysts. When the catalysts were used, 99% removal of the tar and
10% volume increase in the generation of H 2 were observed [23].
In a study, biomass was used as the raw material for the production of biodiesel,
and crude glycerol was obtained as the significant by-product. Afterward, hydrogen
was produced from this crude glycerol in the presence Ni (OH) 2 decorated on TiO 2
nanotubes under sunlight. In the practice, the TiO 2 nanotubes were prepared first by
hydrothermal method, and later on they were deposited by Ni(OH) 2 quantum dots
via wet impregnation method. For this purpose, TiO 2 particles were dissolved in the
solution of NaOH and placed in the autoclave lined with Teflon at 130 °C for 20 h.
The white product thus obtained was washed with distilled water, dilute HCl, and