National Ammonia Company of Pennsylvania was a manufacturer of refrigerators which utilized the Claude process of sytheic ammonia for the coolant. The company was founded by Dr. Herman F. Dannenbaum (1857-1932) in Philadelphia in 1902. Dannenbaun, an expert in refrigerants, emmigrated to America from Germany in 1881. His son, Walter Dannenbaum (1892-1967) joined the company in 1914, after receiving his bacheler of science degree in chemical engineering from the University of Pennsyvlania in 1913.

In 1924, the chemical company, E.I. du Pont de Nemours & Company (also known as the DuPont Company), organized a corpation called Lazote, Inc. and began purchasing sites in Virigina and West Virigina for plants to manufacture synthetic ammonia using the Claude process. By 1926, Lazote, Inc. was operational and Jasper E. Crane (1881-1969), an expert in plastics and a promienent DuPont executive was brought in to serve as President. In the same year, the National Ammonia Company of Pennsylvania was merged with Lazote, Inc., Walter Dannenbaum was made Vice President. In May 1926, the DuPont Company established a holding company called the du Pont National Ammonia Company, Crane was President and Dr. H. Dannenbaum was Vice President.

In 1929, Lazote, Inc. name was changed to the du Pont Ammonia Corporation and acquired the assets of the du Pont National Ammonia Company which was then dissolved. The du Pont Ammonia Corporation was a wholly owned subsidary until 1931, when the du Pont Ammonia Corporation was dissolved and established as the Ammonia Department within the DuPont Company.