Separation of fine serpentine (SPT) from quartz (QZ) both of d80 close to 20 µm using an eco-friendly microbial exo-polysaccharide, xanthomonas campestris (XCT), as a selective flocculant for SPT was conducted experimentally and substantiated theoretically. The adsorption of XCT onto SPT was observed to decrease with increase in pH, whereas that of QZ was nearly nil beyond pH 2.1. Zeta potential of SPT in presence of XCT decreased with increase in pH further attesting to the adsorption and anionicity of XCT. The FTIR studies confirmed the interaction of XCT with SPT in presence of sodium hexametaphosphate. The nature of intermolecular interactions present in complexes formed on SPT surface was revealed by quantum theory of atoms in molecules to be non-covalent. The electron density difference plot conducted on formed complexes indicated that electrons drifted from XCT to the surface of SPT. Selective flocculation SPT-QZ (1:1) mixture conducted at pH 6 and pH 7.5 in presence of 4 mg/L and 2 mg/L of sodium hexametaphosphate coupled with 100 mg/L of XCT yielded separation efficiency and selectivity ratio of 96.5 % and 71.2, respectively, after three desliming stages. Therefore, XCT is a potential selective flocculant for serpentine.

中文翻译：

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使用野油菜黄单胞菌作为选择性絮凝剂对蛇纹石与石英的表面化学性质和分离进行实验和理论研究


使用环保型微生物胞外多糖——野油菜黄单胞菌（XCT）作为 SPT 的选择性絮凝剂，分离了 d80 接近 20 µm 的细蛇纹石（SPT）和石英（QZ），并进行了实验和理论验证。观察到 XCT 在 SPT 上的吸附随着 pH 值的增加而减少，而 QZ 的吸附在 pH 值超过 2.1 时几乎为零。当 XCT 存在时，SPT 的 Zeta 电位随着 pH 值的增加而降低，进一步证明了 XCT 的吸附性和阴离子性。 FTIR 研究证实了在六偏磷酸钠存在下 XCT 与 SPT 的相互作用。分子中原子的量子理论揭示了 SPT 表面形成的复合物中存在的分子间相互作用的本质是非共价的。对形成的复合物进行的电子密度差图表明电子从 XCT 漂移到 SPT 的表面。在 4 mg/L 和 2 mg/L 六偏磷酸钠以及 100 mg/L XCT 存在下，在 pH 6 和 pH 7.5 下进行选择性絮凝 SPT-QZ (1:1) 混合物，分离效率和选择性比为 96.5%经过三个脱泥阶段后，分别为 71.2 和 71.2。因此，XCT是一种潜在的蛇纹石选择性絮凝剂。