It was more than a century before oxygen was used for any major industrial process. Although frequently used in laboratory scale, oxygen was not economical for large-scale production. In 1895, Carl von Linde perfected a new process for producing large quantities of oxygen, which Air Products and all other industrial gas manufacturers still use over a century later. There are three steps to the process: the extreme cooling of air until it becomes liquid; purification of the liquefied air; separating the various components of the liquid by using the different boiling points of each gas. By controlling temperature and pressure, the gases can be separated.

So if Linde—the founder of one of Air Products' major competitors—invented the process in 1895, where does Air Products fit into the picture?

When Air Products was founded in 1940, oxygen had been used in industrial processes in the United States for four decades. Providing the equipment to generate oxygen was Air Products' founder Leonard Pool's dream. Pool was spurred by two factors: industrial and military needs for oxygen were growing, and the traditional source of oxygen technology, Germany, was rapidly closing its doors to U.S. commerce because of World War II.

At that time, the traditional method of supplying oxygen was to produce it from central plants and then transport cylinders to customers. Pool's innovation was not so much technological, as economic. He reasoned that there was as much oxygen in the atmosphere in a customer's location as anywhere else, so generating facilities—which we now call "on-site plants"—were built adjacent to customer locations. This eliminated expensive distribution costs.

Another Air Products innovation came a few years later. On-site oxygen plants were made larger then individual customers required, so much larger that many smaller customers could be supplied from the same plant operation. Because of the increased efficiency of running larger plants, the "piggyback" concept proved a boon to Air Products.

About oxygen: