LABORATORY EVALUATION AND PROCESSING OF PENNSYLVANIA COAL WASTE MATERIAL FOR POTENTIAL RECOVERY OF TRACE RARE EARTH ELEMENTS

Open Access
Author:
Albertson, Quinn F
Area of Honors:
Environmental Systems Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Mark Klima, Thesis Supervisor
  • Mark Klima, Honors Advisor
  • William Arthur Groves, Faculty Reader
Keywords:
  • Coal
  • Rare Earth Elements
  • Leaching
  • Pressure filtration
Abstract:
This research aims to separate rare earth elements (REE) from gangue material in selected coal-waste samples. The material was evaluated with various lab tests involving a combination of leaching and pressure filtration. The leaching process draws the REE from the surface of the waste material and into the salt solution. Its effectiveness was measured with the results of an inductively coupled plasma mass spectrometer (ICP-MS). Pressure filtration of the coal/solution slurry, the focus of this work, was measured for its time-efficiency as part of the two-step separation process. Varying the feed particle size distribution, solution concentration, and pressure filtration allowed for the evaluation of these effects on the leaching and final separation. From all the varied test conditions, the ICP-MS results showed that grinding was the more effective method of size reduction prior to the purpose of leaching, rather than crushing and screening. The ICPMS results show that a 0.5 M leaching solution produced the best leaching efficiency. Data from the pressure filtration confirms that higher pressure decreases the amount of time needed to separate liquid from solid. It also shows that smaller particle sizes and increased solution concentration slow the filtration process, making the pressure filter more relevant as a choice of solid-liquid separation.