Thermal Analysis
The EERC conducts analyses of organic solids and liquids provided by research entities
within the EERC as well as outside researchers who may not otherwise have access
to the required techniques or instrumentation. The EERC also develops new methods
and improves existing methods for the analysis of organic solids and liquids and
performs small bench-scale reactions under pressure and temperature conditions simulating
those of large-scale reactors.
Laboratory Facilities
The laboratory contains equipment for the analysis of micro (milligram) and macro
(10-gram) samples.
Thermal Analysis Equipment
- Pressurized thermogravimetric analysis: TG-Minireactor capable
of operation at up to 900°C and 600 psig
- Thermogravimetric analysis: DuPont 951 thermogravimetric analyzer
(TGA) interfaced with DuPont 2100 thermal analyzer
- Differential scanning calorimetry: DuPont 910 differential scanning
calorimeter (DSC) interfaced with DuPont 2100 thermal analyzer
- Thermal reactivity: Cahn TGA System 113-DC and 1000 thermal reactivity
system
- Surface area: Micromeritics Flowsorb II 2300 (by arrangement with
the UND Department of Chemical Engineering)
Thermal Analysis Methods
- Coal proximate analysis: Measuring the weight loss of a coal sample
on heating under inert atmosphere allows the moisture and volatile matter to be
determined. Fixed carbon and ash content (with oxygen added) are determined by continuing
the heating under an oxidizing atmosphere.
- Simulated distillation: The volatility of components in a mixture
can be observed with increasing temperature to determine a cumulative distillation
curve.
- Gas adsorption and surface activity: The adsorption of a known
gas can be observed from the weight change of a solid sample. Measuring gas adsorption
and knowing the surface area of the sample allow the surface activity toward a given
gas to be calculated.
- Char preparation and reaction kinetics: Chars can be prepared in
various gases, including steam, at temperatures up to 1000°C or can be
reacted at temperatures of up to 900°C and pressures up to 600 psig.
Subsequent rates of reaction and weight loss in oxygen or a gasification environment,
including steam, CO2, H2/CO, SO2, and NO, can be measured to determine the chemical reactivity
of the char.
- Calorimetry measurements: Characterization of solids and polymers
can include measurements of specific heat capacity, melting points, heats of crystallization,
and heat of reaction of condensed phases. The measurements can be carried out under
ambient pressure or at pressures up to 1000 psig.
Additional Analysis Equipment
- Fourier transform infrared (FT-IR) analysis of product gas effluents
from thermal studies can be added to any of the study methods. It provides real-time
online analysis of gaseous species including SO2, CO2,
CO, NO2, NO, CH4, and other hydrocarbon
carbonyl compounds and even ammonia or water. Spectra of the gas effluents and chromatograms
of individual species or functional groups are produced. Effluent gases can also
be analyzed for elemental mercury (Hg) content online using modern cold-vapor atomic
absorption instrumentation.