盐单胞菌合成纳米钯催化污染物的还原

从浙江舟山盐场筛选出一株盐单胞菌Halomonas salina JX-1，能够合成金属钯纳米颗粒，并应用于催化六价铬Cr(VI)的还原及有机偶氮染料甲基橙（MO）的脱色。通过透射电子显微镜（TEM）、X射线衍射（XRD）、X射线光电子能谱分析（XPS）等分析证实合成了零价纳米钯颗粒。对钯纳米颗粒合成条件的优化实验的结果表明，在菌量OD₆₀₀=1.0、无氯化钠、以甲酸为电子供体时，细菌还原钯的速率最快。电子穿梭体核黄素可加快钯离子还原成钯纳米颗粒。纳米钯颗粒在24 h内对Cr(VI)的还原率高达99%，在1.5 h内对甲基橙的降解率也几乎达到100%。综上，Halomonas salina JX-1合成的纳米钯颗粒对Cr(VI)及甲基橙都有很高的催化活性。

Biosynthesis of nano-palladium by Halomonas salina JX-1 for catalytic reduction of pollutants

A bacterial strain Halomonas salina JX-1 was isolated and screened from a salina of Zhoushan Shuangfeng saltern as a synthesizer of palladium nanoparticles that were further used to reduce chromium (VI) and decolor azo dye methyl orange (MO). Transmission electron microscope (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) confirmed the synthesis of zero-valent palladium nanoparticles by Halomonas salina JX-1. The synthesis parameters were optimized at the same time. Results showed that the highest reduction rate of palladium was achieved when the biomass was 1.0 of OD₆₀₀. The synthesis medium contained formic acid as an electron donor and NaCl was omitted. Addition of riboflavin speeded up the reduction rate of palladium. The synthesized palladium nanoparticles reduced 99% of dosed Cr(VI) in 24 h, and removed 100% of methyl orange in 1.5 h. Collectively, these results showed that the palladium nanoparticles synthesized by Halomonas salina JX-1 can effectively reduce Cr (VI) and methyl orange.