Alaskan Zeolites

Zeolites are a curious group of crystalline compounds that occur naturally and also can be synthesized. An extensive natural deposit occurs in the Talkeetna Mountains north of Anchorage, and there is another near Lake Illiamna on the Alaska Peninsula.

Zeolites have so many uses that University of Alaska geochemist Dan Hawkins likens them to the "Schmoos" that some years ago graced the "Lil' Abner" comic strip. Older readers will remember that a schmoo could do many useful tasks and, when eaten, tasted like fried chicken.

In part, zeolites owe their utility to their ability to absorb and give off water. The word zeolite literally means rock that boils; when strongly heated, zeolites froth and give off water. Another curious characteristic is that zeolites, though rigid in structure, are like sponges in that they contain many holes. One of the significances of this open structure is illustrated by new developments of value for energy storage. The amount of natural gas that can be stored in a 19 cubic foot tank at pressure 2300 psi can be stored in a 8 cubic foot tank of one type of zeolite at only 200 psi. Similarly, it may be feasible to produce hydrogen using wind power, hydropower or solar power during times of peak production and then store the hydrogen in zeolite for later use.

Dr. Hawkins also has suggested that the City of Anchorage, and perhaps other northern cities, might profitably use zeolites to extract methane from sewage for use as fuel.