In one aspect, the technology relates to a method of producing Ac, the method including preparing a phosphate-modified titania material to produce an ion-exchange material, contacting a solution including 229Th with the ion-exchange material to produce a Th-loaded titania material, eluting the Th-loaded titania material with a wash solution to produce an eluted solution containing eluted compounds including 225Ac, concentrating the eluted solution to generate eluted compounds including the 225Ac, and separating the 225Ac from the eluted compounds.