Industrial gas firm Praxair Inc. will spend more than $100 million to add a new carbon monoxide purification unit at its Geismar plant.

The expansion will add 13 million cubic feet of carbon monoxide purification capacity to the facility. Praxair said the unit will help meet accelerating demand in the Mississippi River corridor.

Carbon monoxide is used in making a number of specialty chemicals, including those used to produce polyurethanes for the housing and auto industries. The work is expected to be completed in the second half of 2018.

The Geismar site began producing hydrogen, carbon monoxide and other gas products required by the local chemical and refining industries in the early 1970s. The facility has been integrated into a 90-mile hydrogen pipeline network that stretches from Baton Rouge to St. Charles.

Praxair officials said the latest investment further strengthens the company’s ability to serve an important and growing region.

The Geismar facility has more than a dozen customers ranging from large refineries to biofuel companies.