scholarly journals Influence of silica–alumina support ratio on H2 production and catalyst carbon deposition from the Ni-catalytic pyrolysis/reforming of waste tyres

2017 ◽  
Vol 35 (10) ◽  
pp. 1045-1054 ◽  
Author(s):  
Yeshui Zhang ◽  
Yongwen Tao ◽  
Jun Huang ◽  
Paul Williams
Keyword(s):  
Hydrogen Production ◽  
Catalyst Support ◽  
Coke Formation ◽  
H2 Production ◽  
Hydrogen Yield ◽  
Alumina Support ◽  
Production Of Hydrogen ◽  
Waste Tyres ◽  
Silica Alumina ◽  
Multi Walled Carbon Nanotubes

The influence of catalyst support alumina–silica in terms of different Al2O3 to SiO2 mole ratios containing 20 wt.% Ni on the production of hydrogen and catalyst coke formation from the pyrolysis-catalysis of waste tyres is reported. A two-stage reactor system was used with pyrolysis of the tyres followed by catalytic reaction. There was only a small difference in the total gas yield and hydrogen yield by changing the Al2O3 to SiO2 mole ratios in the Ni-Al2O3/SiO2 catalyst. The 1:1 ratio of Al2O3:SiO2 ratio produced the highest gas yield of 27.3 wt.% and a hydrogen production of 14.0 mmol g-1tyre. Catalyst coke formation decreased from 19.0 to 13.0 wt.% as the Al2O3:SiO2 ratio was changed from 1:1 to 2:1, with more than 95% of the coke being filamentous-type carbon, a large proportion of which was multi-walled carbon nanotubes. Further experiments introduced steam to the second-stage reactor to investigate hydrogen production for the pyrolysis-catalytic steam reforming of the waste tyres using the 1:1 Al2O3/SiO2 nickel catalyst. The introduction of steam produced a marked increase in total gas yield from ~27 wt. % to ~58 wt.%; in addition, hydrogen production was increased to 34.5 mmol g-1 and there was a reduction in catalyst coke formation to 4.6 wt.%.

Hydrogen Production via Catalytic Autothermal Reforming of Desulfurized Jet-A Fuel

2016 ◽  
Author(s):  
Shuyang Zhang ◽  
Xiaoxin Wang ◽  
Peiwen Li
Keyword(s):  
Energy Efficiency ◽  
Hydrogen Production ◽  
Hydrogen Storage ◽  
Coke Formation ◽  
Autothermal Reforming ◽  
Operating Conditions ◽  
Hydrogen Yield ◽  
Fuel Conversion ◽  
Optimal Operating ◽  
Reaction Equilibrium

On-board hydrogen production via catalytic autothermal reforming is beneficial to vehicles using fuel cells because it eliminates the challenges of hydrogen storage. As the primary fuel for both civilian and military air flight application, Jet-A fuel (after desulfurization) was reformed for making hydrogen-rich fuels in this study using an in-house-made Rh/NiO/K-La-Ce-Al-OX ATR catalyst under various operating conditions. Based on the preliminary thermodynamic analysis of reaction equilibrium, important parameters such as ratios of H2O/C and O2/C were selected, in the range of 1.1–2.5 and 0.5–1.0, respectively. The optimal operating conditions were experimentally obtained at the reactor’s temperature of 696.2 °C, which gave H2O/C = 2.5 and O2/C = 0.5, and the obtained fuel conversion percentage, hydrogen yield (can be large than 1 from definition), and energy efficiency were 88.66%, 143.84%, and 64.74%, respectively. In addition, a discussion of the concentration variation of CO and CO2 at different H2O/C, as well as the analysis of fuel conversion profile, leads to the finding of effective approaches for suppression of coke formation.

Bio-electrochemical production of hydrogen and electricity from organic waste

2021 ◽  
Author(s):  
Giorgia De Gioannis ◽  
Alessandro Dell'Era ◽  
Aldo Muntoni ◽  
Mauro Pasquali ◽  
Alessandra Polettini ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Electron Flow ◽  
Dark Fermentation ◽  
Electrochemical Process ◽  
Integrated System ◽  
Galvanic Cell ◽  
Hydrogen Yield ◽  
Cell Coupling ◽  
Production Of Hydrogen ◽  
Acid Metabolites

Abstract This study investigated the performance of a novel integrated bio-electrochemical system for synergistic hydrogen production from a process combining a dark fermentation reactor and a galvanic cell. The operating principle of the system is based on the electrochemical conversion of protons released upon dissociation of the acid metabolites of the biological process and is mediated by the electron flow from the galvanic cell, coupling biochemical and electrochemical hydrogen production. Accordingly, the galvanic compartment also generates electricity. Four different experimental setups were designed to provide a preliminary assessment of the integrated bio-electrochemical process and identify the optimal configuration for further tests. Subsequently, dark fermentation of cheese whey was implemented both in a stand-alone biochemical reactor and in the integrated bio-electrochemical process. The integrated system achieved a hydrogen yield in the range 75.5 – 78.8 N LH2/kg TOC, showing a 3 times improvement over the biochemical process.

scholarly journals Experimental Demonstration and Validation of Hydrogen Production Based on Gasification of Lignocellulosic Feedstock

2018 ◽  
Vol 2 (4) ◽  
pp. 61 ◽  
Author(s):  
Jürgen Loipersböck ◽  
Markus Luisser ◽  
Stefan Müller ◽  
Hermann Hofbauer ◽  
Reinhard Rauch
Keyword(s):  
Hydrogen Production ◽  
Pressure Swing Adsorption ◽  
Production Plant ◽  
Flow Sheet ◽  
Hydrogen Yield ◽  
Fuel Feed ◽  
Worldwide Production ◽  
Lignocellulosic Feedstock ◽  
Production Of Hydrogen ◽  
Pressure Swing

The worldwide production of hydrogen in 2010 was estimated to be approximately 50 Mt/a, mostly based on fossil fuels. By using lignocellulosic feedstock, an environmentally friendly hydrogen production route can be established. A flow sheet simulation for a biomass based hydrogen production plant was published in a previous work. The plant layout consisted of a dual fluidized bed gasifier including a gas cooler and a dust filter. Subsequently, a water gas shift plant was installed to enhance the hydrogen yield and a biodiesel scrubber was used to remove tars and water from the syngas. CO2 was removed and the gas was compressed to separate hydrogen in a pressure swing adsorption. A steam reformer was used to reform the hydrocarbon-rich tail gas of the pressure swing adsorption and increase the hydrogen yield. Based on this work, a research facility was erected and the results were validated. These results were used to upscale the research plant to a 10 MW fuel feed scale. A validation of the system showed a chemical efficiency of the system of 60% and an overall efficiency of 55%, which indicates the high potential of this technology.

scholarly journals Synthesis and Characterization of Co/Ni/CoNi-ZSM-5 Catalyst for Hydrogen Production

2018 ◽  
Vol 156 ◽  
pp. 06013
Author(s):  
Widayat Widayat ◽  
Arianti Nuur Annisa ◽  
Hantoro Satriadi ◽  
Syaiful Syaiful
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Hydrothermal Process ◽  
Coke Formation ◽  
Nickel Catalysts ◽  
Catalyst Synthesis ◽  
Cobalt Nickel ◽  
Crystalline Product ◽  
Production Of Hydrogen

Nickel is commonly used as a catalyst in hydrogen production. However, the use of nickel catalysts in the steam reforming process has the disadvantage of coke formation and high cost. Therefore, in this research, Ni/ZSM-5 catalyst synthesis was used to reduce production cost and an addition of cobalt (Co) metal to avoid coke formation. The method consists of a synthesis of ZSM-5 catalyst using hydrothermal process. Furthermore, the crystalline product was impregnated with the metal cobalt, nickel and combination of cobalt-nickel as much as 2% by weight metal/weight of the catalyst. Then the XRD and EDX characterization of Co/ZSM-5, Ni/ZSM-5, and CoNi/ZSM-5 was done followed by catalytic testing in the production of hydrogen from glycerol using steam reforming process. From XRD characterization results showed that Co/ZSM-5 catalyst has a crystallinity of 78.69%, Ni/ZSM-5 catalyst has 70.04% crystallinity and CoNi/ZSM-5 catalyst has 76.99% crystallinity. Catalytic testing on hydrogen production showed that CoNi/ZSM-5 catalyst produced the highest hydrogen concentration of 1,756.33 ppm while Ni/ZSM-5 catalyst produces 1,240 ppm and Co/ZSM-5 catalyst produces 491 ppm.

Thermodynamic possibilities and constraints of pure hydrogen production by a chromium, nickel, and manganese-based chemical looping process at lower temperatures

2007 ◽  
Vol 61 (2) ◽  
Author(s):  
K. Svoboda ◽  
A. Siewiorek ◽  
D. Baxter ◽  
J. Rogut ◽  
M. Punčochář
Keyword(s):  
Hydrogen Production ◽  
Manganese Oxides ◽  
Point Of View ◽  
Steam Oxidation ◽  
Pure Hydrogen ◽  
Hydrogen Yield ◽  
Nickel Aluminum ◽  
Reducing Conditions ◽  
Production Of Hydrogen ◽  
Oxidation By Water

AbstractThe reduction of chromium, nickel, and manganese oxides by hydrogen, CO, CH4, and model syngas (mixtures of CO + H2 or H2 + CO + CO2) and oxidation by water vapor has been studied from the thermodynamic and chemical equilibrium point of view. Attention was concentrated not only on the convenient conditions for reduction of the relevant oxides to metals or lower oxides at temperatures in the range 400–1000 K, but also on the possible formation of soot, carbides, and carbonates as precursors for the carbon monoxide and carbon dioxide formation in the steam oxidation step. Reduction of very stable Cr2O3 to metallic Cr by hydrogen or CO at temperatures of 400–1000 K is thermodynamically excluded. Reduction of nickel oxide (NiO) and manganese oxide (Mn3O4) by hydrogen or CO at such temperatures is feasible. The oxidation of MnO and Ni by steam and simultaneous production of hydrogen at temperatures between 400 and 1000 K is a difficult step from the thermodynamics viewpoint. Assuming the Ni—NiO system, the formation of nickel aluminum spinel could be used to increase the equilibrium hydrogen yield, thus, enabling the hydrogen production via looping redox process. The equilibrium hydrogen yield under the conditions of steam oxidation of the Ni—NiO system is, however, substantially lower than that for the Fe—Fe3O4 system. The system comprising nickel ferrite seems to be unsuitable for cyclic redox processes. Under strongly reducing conditions, at high CO concentrations/partial pressures, formation of nickel carbide (Ni3C) is thermodynamically favored. Pressurized conditions during the reduction step with CO/CO2 containing gases enhance the formation of soot and carbon-containing compounds such as carbides and/or carbonates.

Effect of Organic Loading Rate on Bio-Hydrogen Production in Continuous Stirred Tank Reactor

2010 ◽  
Vol 113-116 ◽  
pp. 1170-1175
Author(s):  
Zi Rui Guo ◽  
An Ying Jiao ◽  
Xiao Ye Liu ◽  
Yong Feng Li
Keyword(s):  
Hydrogen Production ◽  
Loading Rate ◽  
Clean Energy ◽  
H2 Production ◽  
Organic Loading Rate ◽  
Hydrogen Yield ◽  
Continuous Stirred Tank Reactor ◽  
Organic Loading ◽  
H2 Yield ◽  
Distribution Energy

Hydrogen is a kind of ideal clean energy sources. With low energy consumption, environmental protection and other advantages, biological hydrogen production technology become the hotspot of current study home and abroad. The distribution energy technology for producing hydrogen can get hydrogen when deal with waste water. For finding out the industralized feasibility of continuous H2 bio-production,the ability of H2-production via facultative anaerobe,optimum hydraulic retention time(HRT) and optimum organic loading rate(OLR) were aslo studied. With a temperature of (35±1)°C，HRT of 8 h，the CSTR inoculated with activated sludge ,and the progression is increasing organic loading rate gradually. Six OLRs were examined, ranging from 2 to 12 g COD/L.d, with the mass of molasses ranging from 1.3 to 10 g COD/L. While COD was up to 4g/L(OLR 12kg/(m3•d)), all molasses was utilized and the H2 yield was not significantly influenced by OLR. At the intermediate COD of 6g/l (OLR 18kg/(m3•d)), the H2 yield was maximized at about 30 L/d H2 (mol molasses. Conv.), which was 17.9% and 55.9% higher than those of OLR 6 kg/(m3.d) and OLR 12 kg/(m3.d),respectively. When the influent COD concentration raised to 12g/L(OLR 30kg/(m3•d)), the reactor were overloaded, the hydrogen yield decreased drastically，hydrogen evolution rate decreased to zero. Exceeding OLR would arouse great change of internal environment parameters, such as pH, ALK(aikalinity), ORP(oxidation-reduction potential) in CSTR, and the microbial community structure would change while the metabolism of microorganism was inhibited badly.

scholarly journals Artificial Neural Networks for Predicting Hydrogen Production in Catalytic Dry Reforming: A Systematic Review

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2894
Author(s):  
Van Thuan Le ◽  
Elena-Niculina Dragoi ◽  
Fares Almomani ◽  
Yasser Vasseghian
Keyword(s):  
Systematic Review ◽  
Neural Networks ◽  
Artificial Neural Networks ◽  
Hydrogen Production ◽  
H2 Production ◽  
Dry Reforming ◽  
Hydrogen Yield ◽  
Wide Range ◽  
Metal Supports ◽  
Artificial Neural

Dry reforming of hydrocarbons, alcohols, and biological compounds is one of the most promising and effective avenues to increase hydrogen (H2) production. Catalytic dry reforming is used to facilitate the reforming process. The most popular catalysts for dry reforming are Ni-based catalysts. Due to their inactivation at high temperatures, these catalysts need to use metal supports, which have received special attention from researchers in recent years. Due to the existence of a wide range of metal supports and the need for accurate detection of higher H2 production, in this study, a systematic review and meta-analysis using ANNs were conducted to assess the hydrogen production by various catalysts in the dry reforming process. The Scopus, Embase, and Web of Science databases were investigated to retrieve the related articles from 1 January 2000 until 20 January 2021. Forty-seven articles containing 100 studies were included. To determine optimal models for three target factors (hydrocarbon conversion, hydrogen yield, and stability test time), artificial neural networks (ANNs) combined with differential evolution (DE) were applied. The best models obtained had an average relative error for the testing data of 0.52% for conversion, 3.36% for stability, and 0.03% for yield. These small differences between experimental results and predictions indicate a good generalization capability.

HYDROXYAPATITE-SUPPORTED TRI-METALLIC CATALYST FOR HYDROGEN PRODUCTION FROM STEAM REFORMING OF GLYCEROL

2016 ◽  
Vol 78 (5) ◽  
Author(s):  
Lukman Hakim ◽  
Zahira Yaakob ◽  
Ifa Puspasari ◽  
Wan Ramli Wan Daud
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Economic Value ◽  
Catalyst Support ◽  
Precipitation Method ◽  
Metal Catalyst ◽  
Hydrogen Yield ◽  
Glycerol Water ◽  
Glycerol Conversion ◽  
Metallic Catalyst

Glycerol is a byproduct of biodiesel industry that has high economic value to produce hydrogen as an energy source. The selection of catalyst support for active metal catalyst in hydrogen production is a major concern since it affects the activity of metal catalyst during the steam reforming process of glycerol. Besides that, bio-based material as catalyst support provides attractive choice as it is more environmentally friendly. In this study, hydroxyapatite (HAP) as support material for tri-metallic catalyst Ni-Ce-Cu was prepared using deposition-precipitation method and used in steam reforming reaction of glycerol to produce hydrogen. The catalyst prepared was characterized by BET, FE-SEM, EDX, and TEM. The catalytic activity tests were conducted at atmospheric pressure and temperatures between 400 – 600 oC in a tubular micro-reactor. Glycerol-water ratios used were 1:4, 1:8, and 1:16. It was found that the highest hydrogen yield (55.0%) was obtained at temperature of 600 oC and glycerol-water ratio of 1: 8 with glycerol conversion of 94.0%.

scholarly journals The Role of Surface Texture on the Photocatalytic H2 Production on TiO2

Catalysts ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 32 ◽  
Author(s):  
Francesco Pellegrino ◽  
Fabrizio Sordello ◽  
Marco Minella ◽  
Claudio Minero ◽  
Valter Maurino
Keyword(s):  
Hydrogen Production ◽  
H2 Production ◽  
Hydrogen Production Rate ◽  
Environmental Implications ◽  
Production Of Hydrogen ◽  
Hole Scavenger ◽  
Sacrificial Agent ◽  
The One ◽  
Intensive Work

It has been often reported that an efficient and green photocatalytic dissociation of water under irradiated semiconductors likely represents the most important goal for modern chemistry. Despite decades of intensive work on this topic, the efficiency of the water photolytic process under irradiated semiconductors is far from reaching significant photocatalytic efficiency. The use of a sacrificial agent as hole scavenger dramatically increases the hydrogen production rate and might represent the classic “kill two birds with one stone”: on the one hand, the production of hydrogen, then usable as energy carrier, on the other, the treatment of water for the abatement of pollutants used as sacrificial agents. Among metal oxides, TiO2 has a central role due to its versatility and inexpensiveness that allows an extended applicability in several scientific and technological fields. In this review we focus on the hydrogen production on irradiated TiO2 and its fundamental and environmental implications.

A Review of Hydrogen Production Technologies

2003 ◽  
Author(s):  
D. Yogi Goswami ◽  
Samantha T. Mirabal ◽  
Nitin Goel ◽  
H. A. Ingley
Keyword(s):  
Hydrogen Production ◽  
Economic Analysis ◽  
Fossil Fuels ◽  
Renewable Energy Sources ◽  
Thermal Power ◽  
H2 Production ◽  
Production Of Hydrogen ◽  
Recent Developments ◽  
Production Technologies ◽  
Photoelectrochemical Hydrogen Production

This paper describes an overview of the present status of the conventional hydrogen production technologies and some of the recent developments in the production of hydrogen using solar energy resources. It was found that conversion of fossil fuels and biomass, electrolysis of water using solar and wind energy, and direct solar conversion by thermochemical means are some of the most significant methods of H2 production. The technological status and economic analysis for commercial and near commercial technologies using renewable energy sources such as electrolysis using PV and solar thermal power, photochemical and photoelectrochemical hydrogen production, direct thermal decomposition of water, thermochemical cycles, and biological hydrogen production are outlined. Although fossil fuels are currently the least expensive and most widely used sources of hydrogen production, it is argued from an economic analysis that renewable sources of hydrogen are the most promising options for the future. Further, solar hydrogen becomes a storable fuel that is produced from this non-storable and intermittent source of energy.

Sign in / Sign up

Export Citation Format

Share Document