Catalytic activity of biomass-supported Pd nanoparticles: Influence of the biological component in catalytic efficacy and potential application in ‘green’ synthesis of fine chemicals and pharmaceuticals

Palladized cells as suspension catalyst and electrochemical catalyst for reductively degrading aromatics contaminants: Roles of Pd size and distribution

“…The resulting catalytic activity of the Pd-cell is a function of both the initial crystal nucleation and the subsequent bioreduction to Pd(0) (Yong et al, 2002b). The Pd-cell catalysts showed variable activity for a given reaction probably attributable to strain-specific differences in cell surface (Deplanche et al, 2010(Deplanche et al, , 2014. It had also been found that the relatively large and densely Pd(0) crystals covered on biomass exhibited high catalytic activity towards the degradation of hydrophobic molecules, such as polychlorinated biphenyls (De Windt et al, 2006).…”

A Novel Aerobic Mechanism for Reductive Palladium Biomineralization and Recovery byEscherichia coli

“…This suggested an alternative mechanism of Pd(II) reduction which has not been investigated. E. coli produces bioPd which is comparably active to that produced by D. desulfuricans (Deplanche et al 2014). This also provides a very useful model organism since it is facultatively anaerobic and has well-defined molecular tools to elucidate reaction mechanisms under aerobic and anaerobic conditions.…”

“…(Beauregard et al 2010;Deplanche et al 2014) under which condition hydrogenases are not expressed. Also, cells of E. coli deficient in the three major hydrogenases reduced Pd(II) (albeit slowly: Deplanche et al 2010), and showed larger Pd-nanoparticles located on the outer surface of the cells.…”

“…Other organisms capable of this metal bioreduction include the Gram-negative bacteria Shewanella oneidensis (De Windt et al 2005), Escherichia coli (Deplanche et al , 2014Mabbett et al 2006), Pseudomonas putida, Cupriavidus necator (Søbjerg et al 2009), Cupriavidus metallidurans , Paracoccus denitrificans , Rhodobacter sphaeroides (Redwood et al 2008), Rhodobacter capsulatus , and the Gram-positive bacteria Bacillus sphaericus (Creamer et al 2007), Arthrobacter oxyidans (Deplanche et al 2014;Wood et al 2010), Micrococcus luteus (Deplanche et al 2014), Staphylococcus sciuri (Søbjerg et al 2009) and Clostridium pasteurianum (Chidambaram et al 2010).…”

“…A number of studies have investigated the catalytic activity of bioPd, demonstrating its use in remediative reactions such as the reduction of Cr(VI) to Cr(III) (Beauregard et al 2010;Mabbett et al 2006), the dehalogenation of chlorophenol, polychlorinated biphenyls, polybrominated diphenyl ethers (Baxter-Plant et al 2003;De Windt et al 2005;Harrad et al 2007), trichloroethylene (Hennebel et al 2009a(Hennebel et al , 2009b, and the pesticide g-hexachlorocyclohexane (Mertens et al 2007), in "greener" chemical synthesis such as the hydrogenation of itaconic acid (Creamer et al 2007) and 2-pentyne , in Heck and Suzuki reactions (Bennett et al 2013;Deplanche et al 2014), and also in the application of bioPd as a fuel cell electrocatalyst to produce electricity from hydrogen (Orozco et al 2010;Yong et al 2007). In each case where the bioPd was compared with an abiotically produced palladium catalyst (finely divided or supported on a carbon matrix), the bioPd was more active than or at least as active as the commercially available alternative.…”