hydrotalcite
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Hydrogen Production by Methane Decomposition using Hydrotalcite Based Catalyst
Research Proposal DefenceUmair Sikander
(G02960)Nov 28, 2014
Supervisor: A.P. Dr. Suriati bt SufianCo-supervisor: A.P. Dr. Ku Zilati Ku Shaari
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O u t l i n e
Problem Statement
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Research Objectives
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Introduction
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Literature Review
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Research Methodology
Expected Results
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Hypothesis
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Hydrogen is without doubt the best source of energy available and saying that it’s the oldest source of energy is not wrong.
Based on its calorific value Hydrogen is the best energy source available.
It can be used in combustion engines, as a propellant, an explosive, a source of electricity (PEM-Fuel Cells) etc.
0.1Gton of hydrogen is produced annually, of which 98% is being produced from fossil fuels by reforming techniques.
INTRODUCTION
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Methane is the best source material for Hydrogen production; having highest Hydrogen-Carbon ratio.
Increasing demand of COx free hydrogen; has led research towards new green technology for industrial and automobile applications.
Methane Decomposition (MDe) Process is a possible candidate as Carbon is the only By-Product.
CH4 C + 2H2
INTRODUCTION
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High energy requirements since MDe occurs at 1200oC.
Overall process efficiency is limited to 30-40% High Carbon deposition on catalyst surface,
reduce active surface area. Low residence time and hydrodynamic
complexities in MDe Reactors. Continuous catalyst regeneration process.
PROBLEM STATEMENT
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Hydrotalcite is a double layered structure and is used widely for synthesis of CNTs and CNFs, proving to have a high carbon adsorption.
Metallic active sites can be impregnated on its surface using co-precipitation methods.
Hydrotalcite based catalyst have been used for Methane Steam Reforming and other process of Hydrogen Production.
These attributes make it an ideal catalyst for Hydrogen Production by MDe process.
HYPOTHESIS
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Fluidized-bed reactors (FBR) and packed-bed reactors (PBR) are the most commonly used.
Increase in Pressure Drop, Hi Carbon deposition, density alterations are major issues with PBR.
Continuous addition and withdrawl of solids make FBR more suitable for MDe.
Fluidization in FBR increased heat and mass transfer rates.
HYPOTHESIS
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Synthesis and characterization of metallic-HTlcs nano catalyst using soft synthesis methods.
Analysis of synthesized nano-catalyst for hydrogen production by MDe.
Development of Kinetic and Hydrodynamic Modeling Equations
CFD modeling for Fluidized Bed Reactor Design
OBJECTIVES
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ProcessTotal hydrogen
production cost in USD for 100 ft3
Methane decomposition 2.29Hydrocarb process 5.82Steam reforming 2.06Coal gasification with electricity chemical shift (Westinghouse)
4.51
Partial oxidation 3.12High temperature steam electrolysis 5.06Texaco gasification 4.35Coal gasification with high temperature electrolysis 4.43K-T gasification 5.12Water electrolysis 6.57
LITERATURE REVIEW
Marba´n G, Valde´s-Solı´s T. Towards the hydrogen economy? Int J Hydrogen Energy 2007;32:1625–37
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Major efforts are in the use of solar thermal energy.
hi-Temp of 1500-1800oC.
hi Black Carbon deposits
Direct Thermal
Decomposition
Fluidized bed reactors are generally used
Temp. range of 600-900oC
Continuous catalyst regeneration
Thermo-Catalytic
Decomposition
Types of MDe
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Cu, Fe, Co, Ni, Pt, Pd have been studied extensively Minimum reported Temperature for efficient MDe
is 552oC MDe catalytic activity for the iron group metals is:
Ni > Co > Fe.
CATALYSTS in MDe
Ni/γ-Al2O3 catalyst have shown highest Methane to Hydrogen conversion efficiency
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An experimental study for Ni catalyst with loadings in the 5–90% range
CATALYSTS in MDe
Venugopal A, Naveen Kumar S, Ashok J, Hari Prasad D, Durga Kumari V, Prasad KBS, et al. Hydrogen production by catalytic decomposition of methane over Ni/SiO2. Int J Hydrogen Energy 2007;32:1782e8.
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Comparison between different support materials for same active surface area
CATALYST SUPPORT
lower the interaction between active and the support material longer the MDe
Takenaka S, Ogihara H, Yamanaka I, Otsuka K. Decomposition of methane over supported-Ni catalysts: effects of the supports on the catalytic lifetime. Appl Catal A 2001;217:101e10.
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Hydrotalcite based Catalysts
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Reactors in MDe
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Overview of Literature SurveyGroup Catalyst Used Studies Findings
Snoeck et al. Ni/γ-Al2O3 Optimal Temp range High Methane Conversion Efficiency at lowest Temperature of 650oC
Avdeeva et al. Cobalt Less catalytic Deactivation High toxicity, low activityQiang Sun et al. Iron Cheaper Material Low catalytic activityVenugopal et al. Nickel Effect of temperature Below 500oC catalytic deactivation increased
rapidlyEchegoyen et al. Cu doped Ni catalyst Addition of different %ages of Cu 3% doping shows better Methane
ConversionFigueiredo La2O3 doped on Ni-Cu Effect of Lanthanide doping Shows better results of doping over Ni-Cu
catalyst as compared to NiGac et al. Magnesia doping over
different catalystEffect of Magnesia doping Stronger adsorption sites initially, non-linear
catalytic activity.Venugopal et al. Ni/SiO2 Ni loadings in 5-90% range MDe increased till 30% Ni loading
Aielo et al. 70%Ni-10%Cu-10%Fe/Al2O3
Effects of different loading %ages Addition of Fe increases catalyst stability till Temp of 750oC
Jang et al. Fe supported on Alumina Effects of support on Fe catalyst Rapid deactivation below 7500C, high Methane conversion for 100min
Ammendola et al. Cu supported on Alumina Effect of support on Cu catalyst 90% methane conversion but for 5% diluted Methane and only for 90 minutes
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Suelves et al. Carbon black and activated Carbon
Comparison between two types of catalyst
Carbon black shows better conversion and activated carbon rapidly deactivates
Li et al. Ni/γ-Al2O3 Catalytic activity tests Catalyst easily reduced between 500-750oC
Ermakova et al. Ni & Fe on SiO2 Effects of Silica support Yield drops due to formation of metallic silicates
Takenaka et al. Ni over various supports Effects of different support materials
Lower the interaction between support and Ni, higher the yield
Group Catalyst Used Studies Findings
Overview of Literature Survey
Continued
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Methodology
•Literature Review
•Synthesis of Metallic HT based catalyst
•Characterization of Catalyst
•H2 production by MDe in Fluidized Reactor
•CFD studies for optimal reactor Design
•Thesis Writing and Submission
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Synthesis of Metallic HT based catalyst
Methodology
Continuous stirring
After 12hr agingPrecipitates washed and dried for 12hr
Calcination at 1100K for 1day
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Characterization of Catalyst
Methodology
Characterization Technique Analysis
FE-SEM Surface Morphology will be measured by examining the topography using FE-SEM.
FTIR Analysis To measure the functional group attachment.
TGATo measure the thermal stability of catalyst, as high temperature is required for methane decomposition.
XRD AnalysisTo measure the crystallinity of catalyst and to investigate the molecular structure.
XPS analysisCatalyst structure uniformity and surface adsorption will be analyzed using XPS analysis.
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Methodology
H2 production by MDe in Fluidized Reactor
Effect of Temperature Pressure Drop Carbon deposition Extent of Reaction Catalyst regeneration
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CFD studies for optimal reactor Design
• ANSYS FLUENT will be used• Dual sub-modeling approach• Euler-Euler based two fluid Model• Isothermal reactor system
Methodology
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MFIX Model by NETL, USA for Hydrodynamics For reaction kinetics, Gidaspow theory for
Granular Flow Reaction Mechanism developed by Muradov
(CH4)g → (CH3)a + (H)a (1)(CH3)a → (CH2)a + (H)a (2)(CH2)a → (CH)a + (H)a (3)(CH)a → (C)a + (H)a (4)n(C)a → 1/n(Cn)c (5)2(H)a → (H2)g (6).
Methodology
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Set Boundary Conditions
Develop Reactor Geometry & Meshing using Gambit
Define Physical properties (Euler-Euler Two phase Flow)
Incorporate Gidaspow Kinetic Model and MFIX
Hydrodynamic Model
Initialize
ConvergeNO
Modify Mesh size or B.C.
According to Experimental
/Reported Data
YES
Modify Kinetic/Hydrodynamic
Model
NO
Methodology
YES
Optimized Reactor Design
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In a Nut-Shell
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A green future fuel (Hydrogen) production technology.
Potential catalytic nanomaterials for hydrogen production.
Optimized fluidized reactor design for hydrogen production.
Expected Results
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Fist Year 2nd Year 3RD Year
3 years Semester1 (July 2014) Semester 2 (Jan 2015) Semester 3 (July 2015) Semester 4 (Jan 2016) Semester 5 (July 2016) Semester 6 (Jan 2016)
Task 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12Literature Review
Ordering of Chemicals
Synthesis of Catalyst
Characterization of Catalyst
Hydrogen production Studies
Post production Characterization
R E A C T O R M O D E L I N GDeveloping Modeling Eq
CFD Modeling
Thesis Writing & Submission
Gantt Chart
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Thank YouQ&A
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