54
5 Biomass Decomposition and Nanotechnology
ethyl alcohol. The washed product was calcined at 350 °C for 5 h. Afterward, Ni
was loaded on the prepared nanotubes by using the aqueous solution of Ni (NO 3 ) 2 ·
6H 2 O. The mixture was constantly heated while being stirred to remove the excessive
solvent. At the end of the reaction, fine product was obtained which was dried at 80 °C
and calcined at 350 °C for 3 h. The prepared product was analyzed with XRD and
TEM. The characterization of the product showed that the TiO 2 nanotubes have
length and diameter in the range of 100–300 nm and 4.9–9.8 nm, respectively. The
quantum dots of Ni(OH) 2 decorated on nanotubes showed the average particle size
of 8.4 nm. The XPS studies indicated that Ti and Ni are present in the oxidation
state of Ti
4+ and Ni
2+ in the prepared nanomaterials. 4719 μ mol/h H 2 generation
was achieved under solar irradiation from the biomass-based glycerol via the use of
prepared nanomaterials [24].
Some studies have used different nanomaterials in supercritical water gasification
of biomass for the generation of hydrogen. Dennis et al. have reported the use of Ptcarbon nanotubes in the generation of sustainable hydrogen from supercritical water
reforming of acetic acid and ethylene glycol (biomass products). For the preparation
of the nanomaterials, pre-made carbon nanotubes were used without any additional
purification. H 2 PtCl 6 .6H 2 O was used for the loading of the Pt on the nanotubes with
wet impregnation method. In the practice, the solution of H 2 PtCl 6 .6H 2 O was made
in acetone and added to the carbon nanotubes. The excessive solvent is evaporated by
placing the system in vacuum at 100 °C. Afterward, the nanocatalysts were subjected
to 500 °C temperature for 15 h in reducing atmosphere of H 2 and N 2. The loading of
the Pt on the nanotubes was determined by X-ray fluorescence spectrometer (XFS);
surface area was determined by Brunauer–Emmett–Teller (BET); and the surface
morphology of the pure nanotubes and the loaded nanotubes was determined by
SEM, X-ray photoelectron spectrum (XPS), TEM, XRD, and Raman spectroscopy
[25].
Ethylene glycol is a simple modeled compound of ethylene biomass-derived
liquids. It can be used for the production of sustainable hydrogen via steam reforming.
In an investigation, Ni-Pt bimetallic nanocatalysts were used for the steam reforming
of ethylene glycol. The study reported 60% conversion of the hydrocarbon and 27%
yield of the hydrogen at optimized conditions. The bimetallic catalysts were synthesized by the wet impregnation method. For this purpose, firstly the solutions were
made from Ni (NO 3 ) 2 · 6H 2 O and H 2 PtCl 6 · 6H 2 O and were later on mixed with
γ -aluminum oxide and stirred in a rotary evaporator at 60 °C. The reaction was
allowed to take place for 5 h. Afterward, the product was collected, dried (90 °C),
and calcined (600 °C) for 6 h. The synthesized catalysts were analyzed with TEM,
BET, XRD, H 2 -chemisorption, and H 2 -TPR. The introduction of the Pt in the lattice
of the Ni increased the reducibility of the catalyst which leads to the improved metal
dispersion, greater coking resistance, and better oxygen consuming activity. This
leads to the better conversion of the hydrocarbon and improved yield [26].
5 Biomass Decomposition and Nanotechnology
ethyl alcohol. The washed product was calcined at 350 °C for 5 h. Afterward, Ni
was loaded on the prepared nanotubes by using the aqueous solution of Ni (NO 3 ) 2 ·
6H 2 O. The mixture was constantly heated while being stirred to remove the excessive
solvent. At the end of the reaction, fine product was obtained which was dried at 80 °C
and calcined at 350 °C for 3 h. The prepared product was analyzed with XRD and
TEM. The characterization of the product showed that the TiO 2 nanotubes have
length and diameter in the range of 100–300 nm and 4.9–9.8 nm, respectively. The
quantum dots of Ni(OH) 2 decorated on nanotubes showed the average particle size
of 8.4 nm. The XPS studies indicated that Ti and Ni are present in the oxidation
state of Ti
4+ and Ni
2+ in the prepared nanomaterials. 4719 μ mol/h H 2 generation
was achieved under solar irradiation from the biomass-based glycerol via the use of
prepared nanomaterials [24].
Some studies have used different nanomaterials in supercritical water gasification
of biomass for the generation of hydrogen. Dennis et al. have reported the use of Ptcarbon nanotubes in the generation of sustainable hydrogen from supercritical water
reforming of acetic acid and ethylene glycol (biomass products). For the preparation
of the nanomaterials, pre-made carbon nanotubes were used without any additional
purification. H 2 PtCl 6 .6H 2 O was used for the loading of the Pt on the nanotubes with
wet impregnation method. In the practice, the solution of H 2 PtCl 6 .6H 2 O was made
in acetone and added to the carbon nanotubes. The excessive solvent is evaporated by
placing the system in vacuum at 100 °C. Afterward, the nanocatalysts were subjected
to 500 °C temperature for 15 h in reducing atmosphere of H 2 and N 2. The loading of
the Pt on the nanotubes was determined by X-ray fluorescence spectrometer (XFS);
surface area was determined by Brunauer–Emmett–Teller (BET); and the surface
morphology of the pure nanotubes and the loaded nanotubes was determined by
SEM, X-ray photoelectron spectrum (XPS), TEM, XRD, and Raman spectroscopy
[25].
Ethylene glycol is a simple modeled compound of ethylene biomass-derived
liquids. It can be used for the production of sustainable hydrogen via steam reforming.
In an investigation, Ni-Pt bimetallic nanocatalysts were used for the steam reforming
of ethylene glycol. The study reported 60% conversion of the hydrocarbon and 27%
yield of the hydrogen at optimized conditions. The bimetallic catalysts were synthesized by the wet impregnation method. For this purpose, firstly the solutions were
made from Ni (NO 3 ) 2 · 6H 2 O and H 2 PtCl 6 · 6H 2 O and were later on mixed with
γ -aluminum oxide and stirred in a rotary evaporator at 60 °C. The reaction was
allowed to take place for 5 h. Afterward, the product was collected, dried (90 °C),
and calcined (600 °C) for 6 h. The synthesized catalysts were analyzed with TEM,
BET, XRD, H 2 -chemisorption, and H 2 -TPR. The introduction of the Pt in the lattice
of the Ni increased the reducibility of the catalyst which leads to the improved metal
dispersion, greater coking resistance, and better oxygen consuming activity. This
leads to the better conversion of the hydrocarbon and improved yield [26].