2. CONTENTS
1. Objectives
2. Driving Factors
3. Technology Status
4. Catalysis.
5. Bond Energy.
6. Fuel cells.
7. Photovoltaic Generation.
8. Some thoughts of work.
9. Targeted End Results.
3. Objectives: Rural areas in developing countries have energy crisis due to oil price
increase on one hand and the depletion of traditional fuel resources such as firewood.
In developing countries, the major part of energy requirement is for the domestic use
for cooking, water, lighting and drinking water supply. Methane from biomass which is
abundant in rural areas can be utilized to generate heat and electric energy. To make
this possible, controlling methane pollution and eco friendly energy production,
cracking of methane with no or minimal external agency is essential. Based on this
objective, this proposal for developing a catalyst and characterization of the same for
methane family at low temperature is made.
4. The Driving Factors: Among the renewable Energy Technologies like solar,
wind, biomass etc., biogas has lowest financial input per kWh energy output.
Biogas provides energy and also value added fertilizer, in addition to
providing other benefits like better sanitation, cleaner environment with less
pollution, less smoke related diseases, better quality of life, etc. Biogas is a
decentralized sustainable energy system and fertilizer source. Decentralized
energy sources and systems offer an opportunity in supplementing these
energy needs. The world wide energy shortage has stimulated international
interest in untapped, non depletable sources of energy. Health, sanitation
and waste management are some of the social problems that need be
addressed if quality of life of rural masses is to be improved. Pollution
prevention agencies are attempting to save further ecological strain on the
environment. As per published data, the current energy demand in India for
nominal GDP of 9% is about 400,000MW whereas potential production
capacity is 172,000MW. About 30 – 35% is further reduced as grid loss while
transporting power to rural area. Extensive use of coal is a standing example
for global warming and energy demand. The solution for above man made
disaster is to use cracked methane as a renewable energy source.
5. Technology Status: Large number of feasible renewable energy sources has
been explored and technology has been established. Accessible results have
been published with respect to catalytically cracking hydrocarbons which has
complex molecular structure. Methane and Ethane have simpler molecular
structure when compared with elements like Naptha. Few papers have been
published in respect of cracking methane. Lowest temperature at which
methane upto 90% cracking achieved is 540K. This finding focuses on following
problems.
It requires external energy for accelerating cracking.
Catalyst technology for cracking methane still needs development efforts.
Hence, the approach to develop a suitable catalyst is made to focus the
research work in this area.
6. CATALYSIS:
Catalysis is the process in which the rate of a chemical reaction is either increased
or decreased by means of chemical substance known as Catalyst.
Positive Catalyst And Negative Catalyst.
Catalysts can be divided in to two main types: Heterogeneous and
Homogeneous. Heterogeneous catalyst: Are those which act in different phases
then the reactants. Most Heterogeneous catalyst are solid that act on substrates
in a liquor gaseous reaction mixture. The total surface area of solid as an
important effect on the reaction rate. The smaller the catalyst particle size, the
larger the surface area for a given masses of particles. Heterogeneous catalyst
are typically “Supported” which means that the catalyst is dispersed on a second
material that enhances the effectiveness or minimizes their cost. Some times the
support is merely a surface upon which the catalyst is speed to increase the
surface area.
Homogeneous catalyst: Function in the same face as the reactants, but the
mechanistic principles involved in a in Heterogeneous catalysis are generally
applicable. Typically Homogeneous catalysts are dissolved in a solvent with the
substrates.
7. BOND ENERGY
Bond energy (E) is a measure of bond strength in a chemical bond. For ex: The
C-H bond in a methane is the enthalpy change involved with breaking up one
molecule of methane in to C atom & four Hydrogen radicals divided by 4
Bond energy for single bond is 347 KJ/ mole
Bond energy for double bond is 314KJ/mole
Bond energy for Triple bond is 839KJ/mole
Bond energy for C-H bond is 413KJ/mole
Distance between centers of bonded atoms is called bond lengths or bond
distance. The amount of energy required to break a bond is called bond energy.
8. Fuel Cells
A cell (or combination of cells) capable of generating an electric current by
converting the chemical energy of a fuel directly into electrical energy.
The distinctive feature of this cell is that it uses a solid electrolyte in the form
of an ion exchange membrane. The membrane is non- permeable to the
reactant gases, hydrogen and oxygen, which thus prevents them from
coming into contact.
The desired properties of an ideal ion exchange membrane electrolyte are:
(i) High ionic conductivity. (ii) Zero electronic conductivity.
(iii) Low permeability of fuel and oxidant.
(iv) Low degree of electro- osmosis. (v) High resistance to dehydration.
(vi) High resistance to its oxidation or hydrolysis and,
(vii) Mechanical stability.
9. Photovoltaic Generation
The photovoltaic generation using solar cells (more technically called
photovoltaic cells) produce electricity directly from electromagnetic radiation,
especially light, without any moving parts. The photovoltaic effect was
discovered by Becquerel in 1839 but not developed a power source until 1954
by Chapin, Fuller and Pearson using doped semiconductor silicon.
Photovoltaic power has been one of the fastest growing renewable energy
technologies: annual production f cells grew tenfold from about 50MW in
1990 to more than 500MW by 2003, with this growth continuing since.
Demand has been driven by the modular character, standalone and grid
linked opportunities, reliability, and ease of use, lack of noise and emissions
and reducing cost per unit energy produced.
10. CATALYTIC MATERIALS:
1) Nickel Gauze at 773K
2) Ceria at 1173K
3) Ni / La2O3 / Al2O3 at 923K
4) Pt / NiO – C at 1073K
5) Pt / Al2O3 at 723K
11. Some thoughts about the scope of the work:
Review and consolidation of work already done in relevant area of
cracking methane with catalyst.
Analysis on chemistry of catalytic reaction with respect to complex
hydrocarbon compounds.
Selection and finalizing a suitable catalyst material with experimental
evaluation.
Catalyst process options and selection.
Investigating new activation material for coating and process
formulation based on its properties and functioning.
Realization of catalyst bed in crystal or sponge form with maximum
surface area to volume ratio.
Experimental Model realization for cracking of methane and
development of techniques to separate carbon and hydrogen and other
residuals on real time basis.
Characterization of the integrated system through experimental and
analytical correlation.
Applications.
13. Targeted End result:
Development of a viable technology of catalytic cracking of methane
for harnessing rural energy base and thus solve the energy problems
in tune with environmental friendly system.
By characterizing the system for cryogenic environment, the
methane storage density can be increased by 150 -200 times, thus
reducing to bulkiness of fuel storage system and reduce the system
weight. This is the benefit of online systems.