The successful separation of specularite and aegirite in the flotation process heavily relies on efficient depressants due to their closely similar physical and chemical properties. This study focuses on investigating the specific depressive impact and mechanism of pullulan gum (PG) on specularite and aegirite. The findings from single mineral flotation tests revealed the maximum floatability difference was 49.7 percentage point when pH was 8 and the dosage of PG and DDA were 90 mg/L and 30 mg/L respectively, which indicated that PG selectively depressed specularite while displaying a notably weaker depression effect on aegirite. The selective depressive impact of PG was further affirmed through artificial mineral mixed mineral flotation tests. Additionally, results derived from contact angle measurement, adsorption capacity measurement, Zeta potential measurement, and FT-IR analysis collectively highlighted the significantly higher affinity of PG to the surface of specularite compared to aegirite. This stronger interaction between PG and specularite obstructed the adsorption of DDA onto the latter mineral. Moreover, XPS analysis provided insights indicating that PG chemically adsorbs onto the specularite surface, forming a Fe-O complex via a potential reaction between OH and Fe site. As a result of these comprehensive findings, PG emerges as a promising novel depressant for effectively separating specularite from aegirite.

中文翻译：

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新型抑制剂支链淀粉胶用于镜矿与白云石浮选分离的探索

由于镜矿和白云石的物理和化学性质非常相似，因此在浮选过程中成功分离镜矿和白云石在很大程度上依赖于有效的抑制剂。本研究重点研究普鲁兰胶（PG）对镜面岩和白云石的具体抑制作用和机制。单一矿物浮选试验结果表明，当pH为8、PG和DDA用量分别为90 mg/L和30 mg/L时，最大可浮性差异为49.7个百分点，表明PG选择性地抑制镜矿，同时表现出显着的浮选效果。对白云石的抑制作用较弱。通过人工矿物混合矿物浮选试验进一步证实了PG的选择性抑制作用。此外，接触角测量、吸附容量测量、Zeta 电位测量和 FT-IR 分析得出的结果共同强调了与白云石相比，PG 对镜面石表面的亲和力明显更高。 PG 和镜面矿之间更强的相互作用阻碍了 DDA 对后一种矿物的吸附。此外，XPS 分析表明 PG 化学吸附到镜面矿表面，通过 OH 和 Fe 位点之间的潜在反应形成 Fe-O 复合物。这些综合发现的结果是，PG 成为一种有前途的新型抑制剂，可有效分离镜面岩和白云母。