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.

Theoretical Analysis on the Autothermal Reforming Process of Ethanol as Fuel for a Proton Exchange Membrane Fuel Cell System

2006 ◽  
Vol 4 (4) ◽  
pp. 468-473 ◽  
Author(s):  
Alessandra Perna
Keyword(s):  
Fuel Cell ◽  
Proton Exchange Membrane ◽  
Pem Fuel Cell ◽  
Cell System ◽  
Autothermal Reforming ◽  
Proton Exchange ◽  
Operating Conditions ◽  
Hydrogen Yield ◽  
Fuel Cell System ◽  
Exchange Membrane

The purpose of this work is to investigate, by a thermodynamic analysis, the effects of the process variables on the performance of an autothermal reforming (ATR)-based fuel processor, operating on ethanol as fuel, integrated into an overall proton exchange membrane (PEM) fuel cell system. This analysis has been carried out finding the better operating conditions to maximize hydrogen yield and to minimize CO carbon monoxide production. In order to evaluate the overall efficiency of the system, PEM fuel cell operations have been analyzed by an available parametric model.

Thermodynamic Analysis of the Absorption Enhanced Autothermal Reforming of Ethanol

2013 ◽  
Vol 16 (3) ◽  
pp. 229-237 ◽  
Author(s):  
Virginia Collins-Martínez ◽  
Miguel A. Escobedo Bretado ◽  
Jesús Salinas Gutiérrez ◽  
Miguel Meléndez Zaragoza ◽  
Vanessa. G. Guzmán ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Thermodynamic Analysis ◽  
Hydrogen Concentration ◽  
Autothermal Reforming ◽  
Operating Conditions ◽  
Co2 Absorption ◽  
Carbon Formation ◽  
High Hydrogen ◽  
Molar Ratios ◽  
Co2 Absorbent

Thermodynamic analysis of the absorption enhanced autothermal reforming of ethanol using CaO as CO2 absorbent and O2 in the feed was performed to determine favorable operating conditions to produce a high hydrogen ratio (HR, mols H2-produced/EtOH-feed) and hydrogen concentration in gas product. Steam/Ethanol (S/EtOH) and oxygen/ethanol (O2/EtOH) feed molar ratios were varied in order to find autothermal (?H ? 0) and carbon free operating conditions at 300-900°C and CaO as CO2 absorbent at 1 atm. Carbon formation analysis used S/EtOH = 1.75-2.8, while for hydrogen production varied from stoichiometric; 3:1 to 6.5:1, and O2/ETOH from 0 to 1.0. Results indicate no carbon formation at S/EtOH ? stoichiometric. The absorption enhanced autothermal reforming of ethanol using CaO, O2/EtOH = 0.33, S/EtOH = 6.5 and 600°C, produced an autothermal system with 98% H2 and only a reduction of 9.8% in HR and with respect to the CO2 absorption reforming without O2 feed.

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.%.

Thermodynamic Analysis of Hydrogen Production from Ethanol in Supercritical Water Oxidation

2011 ◽  
Vol 110-116 ◽  
pp. 77-82
Author(s):  
Nawadee Srisiriwat
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Hydrogen Production ◽  
Thermodynamic Analysis ◽  
Supercritical Water ◽  
Water Oxidation ◽  
Equilibrium Composition ◽  
Operating Conditions ◽  
Molar Ratio ◽  
Hydrogen Yield

A thermodynamic analysis was performed for hydrogen production from ethanol reforming and oxidation in supercritical water (SCW) conditions. The minimization of Gibbs free energy was used to calculate the equilibrium composition to investigate the effect of operating conditions, pressure, temperature, H2O2:EtOH molar ratio and H2O:EtOH molar ratio, on product yields. The theoretical results indicated that the yields of hydrogen and carbon monoxide decreased as the pressure increased but a H2/CO ratio at atmospheric pressure was lower than that at SCW conditions. High temperatures increased the efficiency of hydrogen production although the amount of carbon monoxide also increased. The presence of oxygen led to great decreases in methane oxidized to carbon dioxide and water. The spending of some hydrogen oxidized to water resulting in a lower hydrogen yield. High H2O:EtOH ratios increased the yields of hydrogen and carbon dioxide but decreased the methane and carbon monoxide production. It is possible to conclude that high temperature, high H2O:EtOH ratio and low addition of oxygen should lead to best results in the SCWO of ethanol.

scholarly journals Effect of Different Inoculum Combination on Biohydrogen Production from Melon Fruit Waste

2018 ◽  
Vol 7 (2) ◽  
pp. 101-109 ◽  
Author(s):  
Yumechris Amekan ◽  
Dyah Sekar A P Wangi ◽  
Muhammad Nur Cahyanto ◽  
Sarto Sarto ◽  
Jaka Widada
Keyword(s):  
Hydrogen Production ◽  
Operating Conditions ◽  
Production Performance ◽  
Biohydrogen Production ◽  
Cow Dung ◽  
Strictly Anaerobic ◽  
Hydrogen Yield ◽  
Production Type ◽  
Fruit Waste ◽  
Melon Fruit

The natural microbial consortium from many sources widely used for hydrogen production. Type of substrate and operating conditions applied on the biodigesters of the natural consortium used as inoculum impact the variation of species and number of microbes that induce biogas formation, so this study examined the effect of different inoculum source and its combination of biohydrogen production performance. The hydrogen producing bacteria from fruit waste digester (FW), cow dung digester (CD), and tofu waste digester (TW) enriched under strictly anaerobic conditions at 37OC. Inoculums from 3 different digesters (FW, CD, and TW) and its combination (FW-CD, CD-TW, FW-TW, and FW-CD-TW) were used to test the hydrogen production from melon waste with volatile solids (VS) concentration of 9.65 g/L, 37°C and initial pH 7.05 ± 0.05. The results showed that individual and combined inoculum produced the gas comprising hydrogen and carbon dioxide without any detectable methane. The highest cumulative hydrogen production of 743 mL (yield 207.56 mL/gVS) and 1,132 mL (yield 231.02 mL/gVS) was shown by FW and FW-CD-TW, respectively. Butyric, acetate, formic and propionic were the primary soluble metabolites produced by all the cultures, and the result proves that higher production of propionic acid can decrease hydrogen yield. Clostridium perfringens and Clostridium baratii prominently seen in all single and combination inoculum. Experimental evidence suggests that the inoculum from different biodigesters able to adapt well to the environmental conditions and the new substrate after a combination process as a result of metabolic flexibility derived from the microbial diversity in the community to produce hydrogen. Therefore, inoculum combination could be used as a strategy to improve systems for on-farm energy recovery from animal and plant waste to processing of food and municipal waste.Article History: Received February 5th 2018; Received in revised form May 7th 2018; Accepted June 2nd 2018; Available onlineHow to Cite This Article: Amekan, Y., Wangi, D.S.A.P., Cahyanto, M.N., Sarto and Widada, J. (2018) Effect of Different Inoculum Combination on Biohydrogen Production from Melon Fruit Waste. Int. Journal of Renewable Energy Development, 7(2), 101-109.https://doi.org/10.14710/ijred.7.2.101-10

Autothermal Reforming of Ethanol for Hydrogen Production: Thermodynamic Analysis

2013 ◽  
Vol 415 ◽  
pp. 658-665 ◽  
Author(s):  
Nawadee Srisiriwat ◽  
Chananchai Wutthithanyawat
Keyword(s):  
Carbon Monoxide ◽  
Hydrogen Production ◽  
Thermodynamic Analysis ◽  
Equilibrium Composition ◽  
Product Distribution ◽  
Autothermal Reforming ◽  
Hydrogen Yield ◽  
Molar Ratios ◽  
Carbon Monoxide Formation ◽  
Gibbs Free Energy Minimization

This work presents the autothermal reforming (ATR), or called oxidative steam reforming (OSR), of ethanol for hydrogen production. A thermodynamic analysis of product distribution for ATR from ethanol has been performed by using the method of Gibbs free energy minimization. The effect of steam-to-carbon (S:C) and air-to-carbon (A:C) molar ratios under adiabatic temperature of ATR reactor on chemical equilibrium composition of hydrogen rich stream is investigated. An increase of S:C ratio increases an efficiency of hydrogen production while carbon monoxide formation decreases but, however, more energy consumption for preheating reactants is also needed. An increase of A:C ratio in the range between 0 and 1.75 causes an increase of hydrogen yield but at greater A:C ratio, a decrease of hydrogen production and more water formation can be found. The results of the thermodynamic equilibrium show that the predicted hydrogen composition in the reaction of fuel-water-air system at constant temperature is higher than that obtained from experiment in both the absence and presence of catalysts in the OSR reaction when the temperature is fixed at 700 °C. The predicted carbon monoxide is lower than that obtained from the results of non-catalytic reaction but higher than that attained from the presence of catalyst in process.

Parametric Study of an Autothermal Micro Surface Reactor for Hydrogen Production

2010 ◽  
Author(s):  
M. H. Akbari ◽  
A. H. Sharafian Ardakani ◽  
M. Andisheh Tadbir
Keyword(s):  
Hydrogen Production ◽  
Rectangular Cross Section ◽  
Surface Reactions ◽  
Chemical Species ◽  
Space Velocity ◽  
Autothermal Reforming ◽  
Molar Ratio ◽  
Hydrogen Yield ◽  
Governing Equations ◽  
Reactor Model

Hydrogen production through autothermal reforming (ATR) of hydrocarbons, such as methane, is one option of interest for mobile applications of hydrogen fuel cells. In the present study, a numerical investigation of catalytic autothermal reforming of methane in a surface microreactor is presented. A three-dimensional ATR reactor model is developed to simulate the flow and surface reactions in a microchannel of rectangular cross section with 340-μm sides, and total length of 8.5 mm. A four-reaction mechanism is implemented to simulate the surface reactions on a Ni/Al2O3 catalyst. The governing equations in the model include conservations of mass, momentum, energy and chemical species. A CFD code based on the finite-volume method has been developed in-house to solve the governing equations. Validation of the results against available data confirms the accuracy of the numerical approach. The simulation results reveal the dependency of hydrogen yield on space velocity (SV), air/fuel molar ratio (A/F), water/fuel molar ratio (W/F), and the gas feed temperature.

Energy Analysis of Hydrogen Production from Methanol under Atmospheric Pressure and Supercritical Water Conditions

2015 ◽  
Vol 1119 ◽  
pp. 548-553
Author(s):  
Nawadee Srisiriwat
Keyword(s):  
Hydrogen Production ◽  
Reaction Temperature ◽  
Supercritical Water ◽  
Atmospheric Pressure ◽  
Energy Analysis ◽  
Ideal Gas ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Hydrogen Yield ◽  
Water Amount

The energy analysis of hydrogen production from the methanol reforming and oxidation under atmospheric (ATM) pressure and supercritical water (SCW) conditions was performed. The equilibrium hydrogen was investigated by the minimization of the Gibbs free energy based on Peng-Robinson equation of state for high pressure and ideal gas equation for atmospheric pressure. An objective of this study was to obtain the optimum operating conditions to maximize the net hydrogen yield, defined as the hydrogen yield taking into account also the methanol consumed by combustion to generate heat. This was done by investigating the effect of operating parameters over the following ranges: temperatures between 773 and 1273 K, pressures between 0.1 and 25.0 MPa, water-to-methanol (H2O:MeOH) ratios between 1 and 5, and oxygen-to-methanol (O2:MeOH) ratios between 0 and 1.05. At ATM pressure, it was found that the equilibrium hydrogen yield increases with increasing H2O:MeOH ratio but the peak of equilibrium H2yield is at 973 K for higher H2O:MeOH ratio than 1:1. Additionally, the total heat load increases significantly as the reaction temperature and the water amount increase. Therefore, the optimum net H2yield is at the H2O:MeOH ratio of 2:1 and the reaction temperature at 973 K. Under SCW conditions, an increase of temperature and water amount in the system constantly increases the equilibrium H2yield. It means that the high H2O:MeOH ratio and temperature are required in SCW. The presence of oxygen in hydrogen production was investigated that an increase of O2:MeOH ratio constantly decreases the H2yield and also the net H2yield for reaction at ATM pressure whereas under SCW conditions, the equilibrium H2yield and the net H2yield increase with increasing oxygen up to 0.42 and 0.84, respectively.

Activity of Copper and Nickel Loaded on HZSM-5Zeolite Based Catalyst for Steam Reforming of Glycerol to Hydrogen

2014 ◽  
Vol 699 ◽  
pp. 504-509
Author(s):  
Hafizah Abdul Halim Yun ◽  
Ramli Mat ◽  
Tuan Amran Tuan Abdullah ◽  
Mahadhir Mohamed ◽  
Anwar Johariand Asmadi Ali
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Fixed Bed ◽  
Operating Conditions ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Hydrogen Yield ◽  
Impregnation Method ◽  
Glycerol Conversion

The study focuses on hydrogen production via glycerol steam reforming over copper and nickel loaded on HZSM-5 zeolite based catalyst. The catalysts were prepared by using different loading amount of copper (0-10wt%) and nickel (0-10wt%) on HZSM-5 zeolite catalysts through wet impregnation method and was characterized by X-Ray Diffraction (XRD). The performances of catalysts were evaluated in terms of glycerol conversion and hydrogen production at 500°C using 6:1 of water to glycerol molar ratio (WGMR) in a tubular fixed bed reactor. All the catalysts had achieved more than 85% of glycerol conversion except that of 5%Cu loaded on HZSM-5 catalyst. The addition of nickel into 5% Cu/HZSM-5 catalyst had increased the hydrogen yield. Similar trend was observed when copper was added into Ni/HZSM-5 catalyst but using copper loaded on HZSM-5 alone was unable to produce hydrogen compared to using nickel catalyst alone. It showed that copper acted as a promoter for hydrogen production. It was established that a 5wt% of Cu with 10wt% of Ni loaded on HZSM-5 catalyst showed significant improvement in terms of hydrogen yield and gaseous product compositions at selected operating conditions.

scholarly journals Hydrogen Production through Autothermal Reforming of Ethanol: Enhancement of Ni Catalyst Performance via Promotion

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 5176
Author(s):  
Ekaterina Matus ◽  
Olga Sukhova ◽  
Ilyas Ismagilov ◽  
Mikhail Kerzhentsev ◽  
Olga Stonkus ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Structural Characteristics ◽  
H2 Production ◽  
Autothermal Reforming ◽  
Molar Ratio ◽  
Ni Catalyst ◽  
Hydrogen Yield ◽  
Impregnation Method ◽  
Transmission Electron ◽  
Preparation Mode

Autothermal reforming of bioethanol (ATR of C2H5OH) over promoted Ni/Ce0.8La0.2O1.9 catalysts was studied to develop carbon-neutral technologies for hydrogen production. The regulation of the functional properties of the catalysts was attained by adjusting their nanostructure and reducibility by introducing various types and content of M promoters (M = Pt, Pd, Rh, Re; molar ratio M/Ni = 0.003–0.012). The composition–characteristics–activity correlation was determined using catalyst testing in ATR of C2H5OH, thermal analysis, N2 adsorption, X-ray diffraction, transmission electron microscopy, and EDX analysis. It was shown that the type and content of the promoter, as well as the preparation mode (combined or sequential impregnation methods), determine the redox properties of catalysts and influence the textural and structural characteristics of the samples. The reducibility of catalysts improves in the following sequence of promoters: Re < Rh < Pd < Pt, with an increase in their content, and when using the co-impregnation method. It was found that in ATR of C2H5OH over bimetallic Ni-M/Ce0.8La0.2O1.9 catalysts at 600 °C, the hydrogen yield increased in the following row of promoters: Pt < Rh < Pd < Re at 100% conversion of ethanol. The introduction of M leads to the formation of a NiM alloy under reaction conditions and affects the resistance of the catalyst to oxidation, sintering, and coking. It was found that for enhancing Ni catalyst performance in H2 production through ATR of C2H5OH, the most effective promotion is with Re: at 600 °C over the optimum 10Ni-0.4Re/Ce0.8La0.2O1.9 catalyst the highest hydrogen yield 65% was observed.

Sign in / Sign up

Export Citation Format

Share Document