Advancements in sustainable platinum and palladium recovery: unveiling superior adsorption efficiency and selectivity with a novel silica-anchored acylthiourea adsorbent† † Electronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d3ra08169a
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SUBMITTER: Mphahlele M
PROVIDER: S-EPMC10910266 | biostudies-literature | 2024 Mar
REPOSITORIES: biostudies-literature
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Project description:Here we demonstrate, a facile in-situ strategy for the synthesis of environmentally benign and scalable graphene sand hybrid using date syrup as a sustainable carbon source through pyrolysis at 750 °C. Raman and SEM images revealed that the as-prepared date syrup-based graphene sand hybrid (D-GSH) had imperfections with macroporous 2-D graphene sheet-like structures stacked on the inorganic sand support. The applicability of the D-GSH for decontaminating the water from cationic (Methyl Violet, MV) and anionic (Congo Red, CR) dye and heavy metals (Pb2+ and Cd2+) was tested. Batch experiments demonstrated that D-GSH showcased exceptional capability for both dye and heavy metals removal with fast adsorption following pseudo-second-order kinetics. The adsorption capacities for MV, Pb2+, and Cd2+ were respectively 2564, 781 and 793 mg/g at 25 °C, the highest capacity graphene-based adsorbent reported in the literature to date. In addition, D-GSH also exhibited high adsorption capacity for anionic dye, CR (333 mg g-1) and good recyclability (3 cycles) for all the contaminants. The thermodynamic studies further confirmed that the adsorption of all contaminants was thermodynamically feasible, spontaneous and endothermic with ∆H° of 48.38, 89.10, 16.89 and 14.73 kJ/mol for MV, CR, Pb2+ and Cd2+, respectively. Thus, utilization of a simple one-step strategy to produce graphenic sand hybrid using date syrup helped in developing a cost-effective and environmentally friendly dye and heavy metal scavenger that can be used as a one-step solution for water decontamination.
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Project description:Platinum and palladium are highly sought-after noble metals that due to their low abundance have high value and because of their stability and their roles in catalytic processes are very desirable for industrial purposes. Bacteria are able to produce nanoparticles of platinum and palladium at low temperatures and from low concentration feedstocks contrary to chemical methods and so pose a potentially untapped ‘green’ resource for nanoparticle synthesis. We have used the bacterium Desulfovibrio alaskensis G20 to reduce Pt and Pd ions to zero-valent nanoparticle forms and used differential shotgun proteomics to identify proteins responsible for this reduction . There was found to be a core set of 13 proteins common to both datasets as well as 7 proteins specific to Pt and Pd individually. Over expression of one of Pt-specific genes; the NiFe hydrogenase small subunit, resulted in the formation of larger nanoparticles. For the first time the proteins involved in the metal reduction pathway have been pinpointed and it is our hope that these target genes can then be used for nanoparticle production to tailor specific properties for industrial purposes at the genetic level rather than post-production.
2021-08-30 | PXD004457 | Pride