EARTH

[3913-23-05] Selective Separation of Platinum Group Metal from Automotive Catalysts using p-dialkylaminomethylcalix[4]arenes

○Muniyappan Rajiv Gandhi¹, Manabu Yamada¹, Yu Kaneta¹, Yetian Hu¹, Atsushi Shibayama¹ (1. Akita University)

Chairman: Carlito Tabelin （Hokkaido University）

Keywords:Calix[4]arenes, Platinum group metals, Liquid-liquid extraction, Automotive catalysts

Platinum group metals (PGMs) are utilized in many fields. Much of the total global production of the three PGMs Pt, Pd, and Rh (ca. 40% of Pt, ca. 58% of Pd, and ca. 83% of Rh) is used in automobile converters to protect the environment and human health from harmful car exhaust. However, the content of PGMs in ores is very low (ca. 1–2 g/ton). PGM-bearing ores are generally located in only certain countries. Spent automotive catalytic converters might contain up to 2000 g/t) of PGM in the ceramic catalyst brick, the active part of the converter. To date, no effective extractants have been developed for complete recovery of PGMs from secondary resource. Therefore, novel PGMs extractants with a higher extraction rate, superior durability, and highly selective for PGMs required. Calixarenes are bowl-shaped structures and are possible to orderly introduce functional groups that possess high affinity for PGMs. Herein, we report synthesis of three p-dialkylaminomethylcalix[4]arenes (propyl=1; butyl=2; and amyl=3) to investigate their abilities in the liquid-liquid extraction of PGMs from single-component PGM solutions, simulated mixed PGM solutions, and leach liquors of automotive catalysts.