Thermal AnalysisDifferent TechniquesBasic PrincipleTGADSCSlide 6DTADTA + DTGTMASlide 10DMAWe have TGA - onlySlide 13TGA – Ca(C204)*xH2ODifferent Heating RatesHeating RatePrecipitated Zr5O8(SO4)2*15 H2OAnalysis of Filtrate from PrecipitationThermal AnalysisTerry A. Ring Chemical EngineeringUniversity of UtahDifferent Techniques•Thermometric Titration (TT)–Heat of mixing•Thermal Mechanical Analysis (TMA)–Thermal Expansion Coefficient•Dynamic Mechanical Analysis (DMA)–Viscoelastic Properties•Differential Scanning Calorimetric (DSC)–Heat flow during Transitions•Thermal Gravimetric Analysis (TGA)–Weight Loss due to decomposition–Derivative Thermogravimetric Analysis (DTG)•Differential Thermal Analysis (DTA)–Heat of Transitions•Temperature Programmed Desorption (TPD)–Temperature at which gas is desorbed from (catalyst) surface–Emission gas Thermoanalysis (EGT)Basic Principle•Sample is heated at a constant heating rate•Sample’s Property Measured–Wt TGA–Size TMA–Heat Flow DSC–Temp DTA–Gas evolved TPDTGA•Constant Heating Rate–Initial Temp–Final Temp–Heating Rate (°C/min)•Data –Weight vs Time–Weight vs Temp.•Differential This Data (DTG)DSCDSC•Constant Heating Rate–Initial Temp–Final Temp–Heating Rate (°C/min)•Data –Heat flow to sample minus Heat flow to reference vs Time (Temp.)•Measures heat of crystallizationPolymer without weight change in this temperature rangeDTA•Sample and Reference Placed in Heater•Constant Heating Rate–Initial Temp–Final Temp–Heating Rate (°C/min)•Data –Temp of Sample vs Time (or Temp)–Temp of Reference vs Time (or Temp)–Reference should be inert, e.g. nothing but latent heat•Measures–Heat of crystallization–Glass Transition TemperatureDTA + DTGTMA•Constant Heating Rate–Initial Temp–Final Temp–Heating Rate (°C/min)•Data –Size of Sample vs Time (or Temp.)•Measures–Thermal Expansion Coefficient–Volume change on crystalization or crystal transformations–Sintering–Glass Transitions in PolymersTMAPolymer with glass transitionDMA•Constant Heating Rate–Initial Temp–Final Temp–Heating Rate (°C/min)•Data –Force vs Time (or Temp.)–Force delay vs Time (or Temp.)–Viscoelastic Properties•Storage and Loss Modulus•Measures–Glass Transition–Viscoelastic PropertiesPolymer with Glass TransitionWe have TGA - only•Heating a sample of Calcium oxalate•Ca(C204)*xH2O  Ca(C204) *H2O + x-1 H2O•Ca(C204)*H2O Ca(C204) + H2O •Ca(C204)  CaCO3 + CO•CaCO3  CaO + CO2TGA•Constant Heating Rate–Initial Temp–Final Temp–Heating Rate (°C/min)•Data –Weight vs Time–Weight vs Temp.•Differential This Data (DTG)TGA – Ca(C204)*xH2ODifferent Heating RatesHeating Rate•Heating Too Fast–Overlaps Transitions•Interpretation Problems•Kinetics of Decomposition–Sample Size–Mass Transfer•Convective Mass Transfer•Pore Diffusion–Heat Transfer•Convective Heat Transfer•Thermal Conductivity–Porous solidPrecipitated Zr5O8(SO4)2*15 H2OThis sample was dried fro 48 hrs at 110C before TGA analysis.What is going on?Analysis of Filtrate from Precipitation•Precipitation•5ZrOCl2 + 2H2SO4 + xH2O  Zr5O8(SO4)2*15 H2O (s) + 10 HCl•Decomposition•Zr5O8(SO4)2*15 H2O (s)  Zr5O8(SO4)2*14 H2O (s) + H2O (v)•Zr5O8(SO4)2  5 ZrO2 (s) +2 SO2