Feralco Iberia, S.A. is the new name of Auxiliar Papelera S.A., after the acquisition by the Feralco group was completed in 2008. Feralco Iberia is the subsidiary of the Feralco Group for the Spanish and Portuguese markets. The Feralco Group, headquartered in Sweden, is a leading manufacturer and marketer of high-performance products for water treatment and the paper industry, with industrial facilities in major European countries.

Feralco Iberia, S.A. is a company that was founded in 1953. It was created to meet the chemical needs of the paper industry in the area and subsequently evolved and expanded its scope of action to water treatment. Its main activity is the manufacture of inorganic coagulants used in the treatment of drinking, industrial and waste water and in the paper industry. It has three industrial sites, located in Alegia and Leaburu (Guipúzcoa) and Valdemoro (Madrid).

Solid aluminium sulphate and various aluminium polychlorides are produced at the Alegia plant; aluminium sulphate in solution is produced at the Leaburu and Valdemoro plants.