Examination of the Thermal Decomposition of Chrysotile

The breaking down of pure chrysotile from Thetford, Quebec heated up at steady temperature in air from 200-1000°C for 4 to 720 hrs has been researched by making use of X-ray diffraction and optical microscopy approaches. No morphological alterations had been noticed optically below 450ºC and 24 hours, although X-ray diffraction data suggest that chrysotile degrades then recrystallizes below 450°C. Throughout the temperature range of 500-1000ºC, changes in the refractive indices noticed involved many cycles of accelerating and reducing magnitudes and ranges. Chrysotile was no longer found above 575°C and Twenty four hours. The minimum temperature of forsterite appearance was at 500°C and 720 hours and also the minimum temperature of enstatite appearance was at 800°C for 8 hours. Extensive insights have been discovered within 500-750°C at 16-8Å, 4Å, and 3Å spacings. These insights suggested the probable existence of talc and tridymite-like mineral phases. X-ray diffraction …

Chapter 1: Introduction and Background
Chapter 2: Previous Work
Thermal Decomposition of Chrysotile
Mechanisms of Dehydration and Recrystallization
Selected Observations from the Literature
Project Scope
Chapter 3: Experimental Design and Analytical Procedures
Sample Preparation
Sample Source

Experimental Procedure
Optical Analysis
X-ray Diffraction Analysis
Chapter 4: Results and Discussion
Overview of Results
Optical microscopy
Heating Times of 4-24 hours
Extended Heating Times
X-ray Diffraction
Heating times of 4-24 hours: chrysotile, forsterite, and enstatite
Extended Heating Times: chrysotile and forsterite
Time-Temperature-Transformation: chrysotile Æ forsterite
Other Phases
Chapter 5: Summary Discussion
Regions of Mineralogical Transformation within Heating Times of 4-24 hours
Mineralogical Transformation within Extended Heating Times
Chapter 6: Conclusions…..

Source: University of Maryland

Leave a Comment