Student Projects for B.Sc. Chemistry

Dr. R. RajeevVSSC, Thiruvananthapuram

Project

• Introduction Relevance Applications Literature survey• Scope of work• Experimental Procedure• Materials• Instrumentation for experiments and characterization• Results & Discussion• Conclusions• Acknowledgements• References

Feasibility

Where to find a topic / subject• Inorganic Chemistry Synthesis of metal oxides• Applications metallurgy, catalysts, fillers in composites, ceramics, pigments,

paints• PropertiesInertness, catalytic activity, stability, purity, colourThermal , electrical , magnetic and spectral propertiesParticle characteristics like size (macro, micro, nano), shape,

surface area, porosity• Properties varies with method of preparation, heat

treatment, precursor

Iron oxide• 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 (FeIII

xFeIIy(OH)3x+2y-z(A-)z; where A- is Cl- or 0.5SO4

2-)

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

• 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)• 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 FormulaPDF 04-006-6579

Ferric Oxide Fe2O3

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 Ammonium Chromate

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

Copper chromite

Atomic Absorption Spectrophotometry (AAS)

Specifications Source : hollow cathode lamp Flame : air/C2H2, N2O/C2H2 Range : 0.1 ppm to 5% Detector : PM tube Sensitivity : 0.01 ppm Sample : aqueous/ non aqueous solutions

• Principle is Beer-Lambert’s law: log I0/I = εcl

• Measurement of radiation, absorbed by the ground state atoms at specific

resonance wavelength, from a hollow cathode lamp

• Extent of absorption is directly proportional to the number of ground state

atoms in the flame, measured by a spectrophotometer

11

Ion Chromatograph

PrincipleIon exchange , retention and elution

ApplicationsAnions and cations from ppm to percentage

levels

Thermogravimetric Analyser (TG) and Differential Thermal Analyser (DTA)

ComponentsBalance assemblies

FurnaceCabinet

Software

Temperature Range: Ambient to 1500°CHeating Rate : 0.1°C/min to100°C/minAccuracy : 1%Balance sensitivity : 0.1gDTA 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°CHeating Rate : 0.1°C/min to 100°C/minCalorimetric Precision : 1 %

UV-Visible Spectrophotometer

SpecificationsRange : 190-900nm Resolution : 1 nm

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 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 Ammonium dinitramide analysis

20

UV-visible spectra of metal complexes

λmax of NiCl2 760 nm, λmax of NiOA is below 650 nm

λmax of CuCl2 754 nm, λmax of CuOA is 650 nm

400 450 500 550

0

1

2

3

Ferric chloride

ferric chloride- Oleyl amine complex

Abso

rban

ce

Wavelength, nm

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 Spectrophotometermax = 410nm, Band width = 0.5nmQuartz cell with optical path length 10mm

0 5 10 15 20

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

slope 0.01591

Calibration graph for Titanium

Abs

orba

nce

Concentration of Titanium (mg/L)400 450 500 550

0

1

2

3

T-H2O2 complex

Abs

orba

nce

Wavelength, nm

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 ProjectsStudies on water crystallization of compoundsSulphate, Double sulphates, alumsNitrates, chlorides, complexesPreparation of crystalsTG, DTA studies, XRD, IR

Catalytic activity studiesAmmonium perchlorate, ammonium nitrate, potassium nitrate, potassium chlorate

Catalysts: Metal oxides, mixed metal oxidesPreparation and characterizationTG, 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-analysisRemoval of minor and trace contaminants -As, Hg, Cr, Fe, Ni, Fluoride, perchlorate, etc-Adsorption, Ion exchange, chromatography, solvent extraction, precipitation, evaporation, volatilization Regeneration, analysisType of additives / by productsNatural, 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 soilTechnologies are required for producing oxygen from this CO2 and from iron oxide

Splitting of water to hydrogen and oxygen by low cost / energy methodStorage of hydrogen