Fabrication of thermosensitive palladium imprinted polymers and evaluation of their adsorption separating performances and practical applications

The excellent physical and chemical properties of palladium(Pd) have made its application and demand increase gradually. Therefore, it is important to develop a new material to efficiently separate and purify palladium from secondary sources to ensure its supply. In this work, a thermosensitive palladium smart imprinted polymer(Pd-T-SIP) was synthesized, which could achieve the efficient separation and purification of Pd. The microstructure and morphology of Pd-T-SIP were characterized. The experimental results showed that the Pd-T-SIP showed the maximum adsorption amount(Q) of 0.1022 mmol/g for Pd(IV), the desorption rate(D) was 83.09%, and it had good reusability. Theoretical studies showed that the adsorption process of Pd-T-SIP was suitable to be described by quasi-first-order model and Langmuir model, which indicated that the adsorption of Pd-T-SIP was monolayer adsorption. Finally, Pd-T-SIP was applied to the platinum group catalyst leach solution, and it could be found that its adsorption/desorption effect was more excellent, with its adsorption amount reaching 0.1558 mmol/L, desorption rate reaching 77.14%, and the palladium purity after one adsorption/desorption cycle increased from 13.75% to 30.62%, and the purity of platinum group metals increased from 40.29% to 73.56% after one adsorption/desorption cycle.