The steel plant, which is being built in Ramos Arizpe, Coahuila, will produce 1.5 million tons of steel annually.
Praxair will construct, own and operate the energy efficient cryogenic air separation unit for the steel company.
Praxair Mexico and Central America president and general director Murilo Melo said Praxair Mexico is committed to providing Deacero and the Mexican market with cutting edge technology, high quality products and reliable gas supply services in order to support its growth, productivity and environmental initiatives.
Operations of the air separation unit, which has a capacity of 500 tons per day, are expected to start in the first semester of 2014.
Deacero is a steel company in Mexico and a wire rod producer.
Praxair Mexico is an industrial and medical gas provider in Mexico.