Transcript Student Projects for B.Sc. Chemistry

Student Projects for B.Sc. Chemistry
Dr. R. Rajeev
VSSC, Thiruvananthapuram
Project
• Introduction
Feasibility
Relevance
Applications
Literature survey
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Scope of work
Experimental Procedure
Materials
Instrumentation for experiments and characterization
Results & Discussion
Conclusions
Acknowledgements
References
Where to find a topic / subject
• Inorganic Chemistry
Synthesis of metal oxides
• Applications
metallurgy, catalysts, fillers in composites, ceramics,
pigments, paints
• Properties
Inertness, catalytic activity, stability, purity, colour
Thermal , electrical , magnetic and spectral properties
Particle characteristics like size (macro, micro, nano),
shape, surface area, porosity
• Properties varies with method of preparation, heat
treatment, precursor
Iron oxide
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Oxides of Iron
iron(II) oxide, wüstite (FeO)
iron(II,III) oxide, magnetite (Fe3O4)
iron(III) oxide (Fe2O3)
– alpha phase, hematite (α-Fe2O3) beta phase, (β-Fe2O3)
– gamma phase, maghemite (γ-Fe2O3)
– epsilon phase, (ε-Fe2O3)
Hydroxides
iron(II) hydroxide (Fe(OH)2)
iron(III) hydroxide (Fe(OH)3), (bernalite)
Oxide/hydroxides
goethite (α-FeOOH),
akaganéite (β-FeOOH),
lepidocrocite (γ-FeOOH),
feroxyhyte (δ-FeOOH),
ferrihydrite (Fe5HO8·4H2O approx.), or 5Fe2O3•9H2O, better recast as FeOOH•0.4H2O
high-pressure FeOOH
schwertmannite (ideally Fe8O8(OH)6(SO)·nH2O or Fe3+16O16(OH,SO4)12-13·10-12H2O)
green rust (FeIIIxFeIIy(OH)3x+2y-z(A-)z; where A- is Cl- or 0.5SO42-)
Synthesis
• Precipitation of from an aqueous solution of
iron compound
• Precipitating agent,, ammonia, NaOH, KOH, amines
• Temperature- RT, Hydrothermal, autoclave, microwave
• Homogeneous precipitation- urea, hexamine
• Thermal decomposition of Iron compounds
• Iron salts – inorganic / organic
• Nitrate, carbonate, sulphate, perchlorate / oxalate, citrate,
tartrate
• Iron complexes• Atmosphere - oxidizing, reducing, inert
Synthesis of Nano Iron oxide particles
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Combustion technique
Vapour deposition
Sol-Gel method
Template method
Homogeneous precipitation
Powdering- ball milling, Fluid energy milling
Characterization techniques
Elemental analysis
• CHNS Analyser
• UV-Visible Spectrophotometry
• Ion Chromatography (IC)
• Atomic Absorption Spectrometry (AAS)
• Inductively Coupled Plasma Atomic Emission Spectrometry (ICPAES)
• X-ray Fluorescence Spectrometry (XRF)
Structural Analysis
• Fourier Transform Infra Red Spectrometry (FTIR)
• X-ray Diffraction Spectrometry (XRD)
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Particle Characterization
• Surface area analyser
• Particle Size analysis by light scattering
• Scanning Electron Microscope (SEM)
• Transmission Electron Microscope (TEM)
• Atomic Force Microscope (AFM)
Thermal Analysis
• Thermogravimetric Analyser (TGA)
• Differential Thermal Analyser (DTA)
• Differential Scanning Calorimeter (DSC)
X-ray Diffraction Spectrometer (XRD)
Nano ferric oxide by sucrose method
Colour
Pattern
Compound Name Formula
PDF 04-0066579
Ferric Oxide
Fe2O3
Copper Ammonium Chromate
Colour
Pattern
Compound Name
Formula
PDF 00-005-0151
Ammonium Copper
Chromium Oxide
Hydroxide
NH4 CuCrO4(OH)
PDF 00-041-0625
Ammonium Copper
Ammine Chromium Oxide
(NH4)2Cu4(NH3)3Cr5O20
Copper chromite
Colour
Pattern
Compound Name
Formula
PDF 01-080-8761
Copper Hydrogen
Chromium Oxide
Cu0.41 Cu0.24 H1.1
Cr2O4
PDF 00-048-1548
Tenorite, syn
CuO
PDF 00-021-0874
Copper Chromium Oxid
CuCr2O4
Atomic Absorption Spectrophotometry (AAS)
Specifications
Source
Flame
Range
Detector
Sensitivity
Sample
: hollow cathode lamp
: air/C2H2, N2O/C2H2
: 0.1 ppm to 5%
: PM tube
: 0.01 ppm
: aqueous/ non aqueous solutions
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Principle is Beer-Lambert’s law:
log I0/I = εcl
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Measurement of radiation, absorbed by the ground state atoms at specific
resonance wavelength, from a hollow cathode lamp
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Extent of absorption is directly proportional to the number of ground state
atoms in the flame, measured by a spectrophotometer
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Ion Chromatograph
Principle
Ion exchange , retention and elution
Applications
Anions and cations from ppm to percentage
levels
Thermogravimetric Analyser (TG) and
Differential Thermal Analyser (DTA)
Components
Balance assemblies
Furnace
Cabinet
Software
Temperature Range: Ambient to 1500°C
Heating Rate : 0.1°C/min to100°C/min
Accuracy
:  1%
Balance sensitivity : 0.1g
DTA sensitivity
: 0. 001°C
TG /DTG and DTA of
FeSO4.7H20
TG /DTG of Fe(NH4)2.(SO4)2.6H20 –
Mohrs. salt
TG /DTG of FeNH4.(SO4)2.12H20
– Ferric alum
Differential Scanning Calorimeter (DSC)
Temperature Range: -150°C to 725°C
Heating Rate : 0.1°C/min to 100°C/min
Calorimetric Precision : 1 %
UV-Visible Spectrophotometer
Principle
Beer-Lambert law
A = log I0/I = εcL
 UV -Visible spectroscopy involves the absorption of UV or visible light by
a molecule causing the promotion of an electron from a ground electronic
state to an excited electronic state
Applications
Specifications
Range
Resolution
: 190-900nm
: 1 nm
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Estimation of trace level impurities in alloys
Estimation of titanium, Iridium in alloys and
catalysts
 Absorption studies of Quantum dots, dyes
 Fe in Al powder
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 Ammonium dinitramide analysis
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Ferric chloride
UV-visible spectra of
metal complexes
Absorbance
2
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ferric chloride- Oleyl amine complex
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Wavelength, nm
λmax of NiCl2 760 nm, λmax of NiOA is below λmax of CuCl2 754 nm, λmax of CuOA is 650
650 nm
nm
550
Analysis of Titanium by UV-visible Spectrophotometer
• In acid medium Titanium ions give an yellow orange complex
with H2O2 which forms the basis of spectrometric method for
determination of Titanium.
• The interference from other elements can be eliminated by
the addition of citric acid / tartaric acid
UV-Visible Spectrophotometer
max = 410nm, Band width = 0.5nm
Quartz cell with optical path length 10mm
Calibration graph for Titanium
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0.35
0.30
slope 0.01591
Absorbance
Absorbance
T-H2O2 complex
2
1
0.25
0.20
0.15
0.10
0.05
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0.00
400
450
Wavelength, nm
500
550
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Concentration of Titanium (mg/L)
Fourier Transform Infra red
Spectrometer
Wavelength range : 400 - 4000 cm-1 Sa
Samples in KBr pellets used for
measuring spectrum
FTIR spectra of OA and CuOA complexes
3300 cm-1 – broadened due to
metal oleyl amine complexes
2854 and 2922 cm-1 Oleyl
group
Topics for Projects
Studies on water crystallization of compounds
Sulphate, Double sulphates, alums
Nitrates, chlorides, complexes
Preparation of crystals
TG, DTA studies, XRD, IR
Catalytic activity studies
Ammonium perchlorate, ammonium nitrate,
potassium nitrate, potassium chlorate
Catalysts: Metal oxides, mixed metal oxides
Preparation and characterization
TG, DTA, DSC, particle size, surface area, XRD, IR, SEM, TEM
Topics for Projects
Pollution control studies
Removal of major contaminants
-acid, base, sulphate, nitrate, perchlorate, fluoride, iron, etc
-Addition of suitable neutralizing /precipitating agents, separation
-analysis
Removal of minor and trace contaminants
-As, Hg, Cr, Fe, Ni, Fluoride, perchlorate, etc
-Adsorption, Ion exchange, chromatography, solvent extraction,
precipitation, evaporation, volatilization
Regeneration, analysis
Type of additives / by products
Natural, synthetic reagents, corrosive, ecofriendly
Topics for Projects
Analytical Chemistry Projects
• Estimation of iron content in soil from
different area by spectrophotometry
• Analysis of Titanium content in beach sand by
spectrophotometry
• Quantitative composition analysis of alloys eg.
Chromium / Nickel content in Stainless steel
(gravimetry, volumetry, colorimetry, AAS, ICP-AES)
Advanced Projects
Mars atmosphere contains >95% CO2
and also as dry ice in soil
Technologies are required for producing
oxygen from this CO2 and from iron oxide
Splitting of water to hydrogen and oxygen by
low cost / energy method
Storage of hydrogen