Date of Award


Document Type


Degree Name

Master of Science (MS)


Chemical Engineering


Activated carbon was produced from carbonized North Dakota lignite using carbon dioxide as an activating agent. A range of carbonizing temperatures, activation temperatures and residence times were investigated. Activated carbons produced were compared to commercial activated carbons using iodine and methylene blue adsorption tests and the heat of wetting test.

Carbons were produced that adsorbed nearly the same amount of methylene blue as the commercial carbons, Darco G-60 and Norit A. The methylene blue adsorption by the best carbons (C63 and C83) was superior to that for the commercial carbons, Calgon Cal and Linde LCK.

An acid washed carbon (C83) had an iodine adsorption comparable to Darco G-60 and better than Calgon Cal but inferior to that for Norit A and Linde LCK.

Analysis of variance using a Latin square design indicated that temperature of activation, temperature of carbonization, and residence time were significant at a 0.05 level for an activation temperature range of 1450 to 2050 °F, carbonization temperature range of 900 to 1350 °F, and residence times of 15, 30, 45, and 60 minutes.

A 15 percent carbon dioxide-85 percent nitrogen mixture was used for the activation of carbonized lignite. The mixture was used to simulate flue gas and to investigate the possible use of flue gas as an activating agent. The carbons produced had relatively low activity when compared to samples activated with only carbon dioxide.

The production of a granular activated carbon from pressed pellets of a mixture of lignite and bentonite produced carbons with durability of 14.1 to 71.1 percent breakage compared to the breakage of 0.2 to 1.5 percent for the commercial granular carbons and 7.2 percent for a granular North Dakota activated carbon.

The removal of ash by mineral acids increased the adsorption of iodine of the best carbon (sample C83) 24 percent but had little effect in the adsorption of methylene blue.