Effective Adsorption of Precious Metal Palladium over Polyethyleneimine-Functionalized Alumina Nanopowder and Its Reusability as a Catalyst for Energy and Environmental Applications

Abstract

Palladium is one of the widely used precious metals toward catalysis, energy, and environmental applications. Efficient recovery and reusability of palladium from the spent catalysts is not only highly desirable for sustainable industrial processing but also for preventing environmental contamination. Here, we present a facile citrate-mediated amine functionalization of alumina nanopowder (AO) in aqueous medium. The surface functionalization is probed using infrared (IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis, surface area, and zeta potential measurements. The amine-functionalized sorbent is thoroughly studied for its vital palladium-sorption parameters such as amount of adsorbent, pH, adsorption capacity, thermodynamics, and kinetics. The palladium adsorption over amine-functionalized AO is further characterized with X-ray diffraction and XPS. IR analysis of palladium adsorbed over polyethyleneimine is performed to elucidate the mechanistic insight on the role of nitrogen in capturing palladium. The amine-functionalized sorbent after adsorbing palladium is studied for the catalytic reduction of 4-nitrophenol and Cr(VI) and hydrogen generation from ammonia borane, which demonstrated its excellent catalytic activity and reusability toward energy and environmental applications. The environmentally benign materials and all-aqueous reactions employed in this work demonstrate the potential of the strategy for efficient and economical industrial transformations and waste-stream management.

Chemically modified rice husk as an effective adsorbent for removal of palladium ions

“…By plotting a relation between C e /q e against C e , a straight line was obtained with a slope equals to 1/q m and an intercept equals to 1/bq m . The q m of Pd 2+ equals 198.2 mg g −1 which is higher than that achieved by other sorbents [ 10 , 39 , 40 , 41 ] as shown in Table (2) . The results also showed that RH@MCM-41@ARS had greater q m compared to that of RH@MCM-41 and RH (16.1 and 13.3 mg g −1 , respectively).…”

“… Method q m (mg g −1 ) Ref. Polyethyleneimine-Functionalized Alumina Nanopowder 97.7 [ 39 ] Poly (N-phenylethanolamine) modified MWCNTs 101 [ 40 ] Cellulose filter paper grafted with polymer chains bearing thiocarbamate moieties 37 [ 41 ] Modified activated carbon 92 [ 10 ] RH@MCM-41@ARS 198.2 Our work …”

Electrochemical recovery of low concentration of palladium from palladium(II) chloride of electroplating wastewater

“…Here, oxygen‐containing groups might serve as mediators between the electrode and the electroactive species 32 . Moreover, RVC has a higher binding energy because of the bonding with oxygen atoms 33 . Pd and Sn in Shipley's solution provide catalytic sites on the substrate for metal nucleation.…”

“…32 Moreover, RVC has a higher binding energy because of the bonding with oxygen atoms. 33 Pd and Sn in Shipley's solution provide catalytic sites on the substrate for metal nucleation. Yap (2009) found that Shipley's solution gives better performance in the gold deposition process on RVC, based on her morphological analysis on RVC after activation with Shipley's solution.…”

Cellulose and Saccharomyces cerevisiae Embark To Recover Europium from Phosphor Powder

“…The increase in adsorption capacity at equilibrium with respect to the initial Eu­(III) concentration is attributed to the fast and effective interaction between Eu­(III) and the surface of the biosorbent . The maximum Langmuir adsorption capacity was calculated through the plot of C e / q e against C e (Figure b), with the linear form of the equation as where C e (mg L –1 ) and q e (mg g –1 ) refer to the equilibrium concentration and the amount of Eu­(III) adsorbed at equilibrium, respectively. q o (mg g –1 ) is the maximum adsorption capacity, and b (L mg –1 ) is the Langmuir constant related to the energy of adsorption.…”