Student Projects for B.Sc. Chemistry Dr. R. Rajeev VSSC, Thiruvananthapuram Project • Introduction Feasibility Relevance Applications Literature survey • • • • • • • • 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 • • • • • • • • • • • • • • • • 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 • • • • • • 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 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 • 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 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 : 0.1g 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 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 20 Ammonium dinitramide analysis 3 Ferric chloride UV-visible spectra of metal complexes Absorbance 2 1 0 ferric chloride- Oleyl amine complex 400 450 500 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 3 0.35 0.30 slope 0.01591 Absorbance Absorbance T-H2O2 complex 2 1 0.25 0.20 0.15 0.10 0.05 0 0.00 400 450 Wavelength, nm 500 550 0 5 10 15 20 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