20120087849 | METHOD FOR RECOVERING LANTHANUM FROM ZEOLITES CONTAINING LANTHANUM - The present invention relates to a method for recovering lanthanum from zeolite compounds containing lanthanum which is characterized in that (A) an aqueous acid is added to one or more zeolite compounds containing lanthanum so that there is a pH value of lower than or equal to 3, and (B) dissolved lanthanum is separated out. The method according to the invention makes it possible when recovering lanthanum from zeolites containing lanthanum to dispense with the use of corrosive gases such as chlorine and hydrogen chloride and with corrosive oxidative molten metals, and thus simplifies the apparatus requirements and the process. The present invention makes it possible to recover lanthanum from zeolite compounds containing lanthanum which occur as catalyst waste from large-scale chemical material conversion processes, such as, for example, the Fluid Catalytic Cracking method (FCC method), the hydrocracking method or the Claus process. | 04-12-2012 |