title: Functional clay supported bimetallic nZVI/Pd nanoparticles used for removal of methyl orange from aqueous solution.
abstract: Bentonite supported Fe/Pd nanoparticles (B/nZVI/Pd) were synthesized as composites that exhibit functionalities assisting in the removal of methyl orange (MO) from aqueous solution. The results showed that 91.87% of MO was removed using B/nZVI/Pd, while only 85% and 1.41% of MO were removed using nZVI/Pd and bentonite after 10 min, respectively. The new findings include that the presence of bentonite decreased the aggregation of nZVI/Pd and nZVI in the composite played its role as a reductant, while Pd(0) acted as the catalyst to enhance the degradation of MO, which were confirmed by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-vis analysis and the batch experiments. The increase in B/nZVI/Pd loading led to greater removal efficiency, while decolorization efficiency declined in the presence of anions such as nitrate, sulfite and carbonate, especially nitrate, which decreased the apparent rate constant k(obs) almost 17.06-fold. The kinetics study indicated that the degradation of MO fitted well to the pseudo-first-order model, where the k(obs) was 0.0721 min(-1). Finally, the reactivity of aged B/nZVI/Pd was investigated, and the application of B/nZVI/Pd in wastewater indicated a removal efficiency higher than 93.75%. This provided a new environmental pollution management option for dyes-contaminated sites.
authors.affiliation: School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China; Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou 350007, Fujian Province, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wang
authors.forename: Jin
authors.initials: J
authors.lastname: Su
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Jin
authors.forename: Zuliang
authors.initials: Z
authors.lastname: Chen
authors.forename: Mallavarapu
authors.initials: M
authors.lastname: Megharaj
authors.forename: Ravendra
authors.initials: R
authors.lastname: Naidu
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D001546:Bentonite / Q000737:chemistry*; D003116:Color; D004396:Coloring Agents / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D014874:Water Pollutants, Chemical; D001546:Bentonite; D010165:Palladium; C100258:methyl orange; D007501:Iron
keywords: Clay; Decolorization; Methyl orange; nZVI/Pd nanoparticles