Rare earth elements (REE) are critical to a wide range of technologies ranging from mobile phones to wind turbines. Processing and extraction of REE minerals from ore bodies is, however, both challenging and relatively poorly understood, as the majority of deposits contain only limited enrichment of REEs. An improved understanding of the surface properties of the minerals is important in informing and optimising their processing, in particular for separation by froth flotation. The measurement of zeta potential can be used to extract information regarding the electrical double layer, and hence surface properties of these minerals.

There are over 34 REE fluorcarbonate minerals currently identified, however bastnäsite, synchysite and parisite are of most economic importance. Bastnäsite–(Ce), the most common REE fluorcarbonate, supplies over 50% of the world's REE. Previous studies of bastnäsite have showed a wide range of surface behaviour, with the iso-electric point (IEP), being measured between pH values of 4.6 and 9.3. In contrast, no values of IEP have been reported for parisite or synchysite.

In this work, we review previous studies of the zeta potentials of bastnäsite to investigate the effects of different methodologies and sample preparation. In addition, measurements of zeta potentials of parisite under water, collector and supernatant conditions were conducted, the first to be reported. These results showed an iso-electric point for parisite of 5.6 under water, with a shift to a more negative zeta potential with both collector (hydroxamic and fatty acids) and supernatant conditions. The IEP with collectors and supernatant was <3.5. As zeta potential measurements in the presence of reagents and supernatants are the most rigorous way of determining the efficiency of a flotation reagent, the agreement between parisite zeta potentials obtained here and previous work on bastnäsite suggests that parisite may be processed using similar reagent schemes to bastnäsite. This is important for future processing of REE deposits, comprising of more complex REE mineralogy.

稀土元素（REE）对于从手机到风力涡轮机的广泛技术至关重要。然而，由于大多数矿床仅含有有限的稀土元素富集，因此从矿体中加工和提取稀土元素矿物既具有挑战性，也相对缺乏了解。更好地了解矿物的表面性质对于告知和优化矿物的加工非常重要，特别是通过泡沫浮选进行分离时。ζ电势的测量可用于提取与双电层有关的信息，并因此提取与这些矿物的表面特性有关的信息。

目前已鉴定出34种以上的REE碳酸盐矿物，但是，bastnäsite，synchsitesite和parisite具有最重要的经济意义。Bastnäsite–（Ce）是最常见的REE碳氟化合物，占全球REE的50％以上。先前对astnäsite的研究表明，其表面行为范围很广，其等电点（IEP）的pH值在4.6至9.3之间。相比之下，没有报告过寄生虫或合寄生虫的IEP值。

在这项工作中，我们回顾了先前对bastnäsite的zeta潜力的研究，以研究不同方法和样品制备的影响。此外，在水，捕收剂和上清液条件下，对寄生虫的ζ电势进行了测量，这是首次报道。这些结果表明，在水中的寄生虫的等电点为5.6，在集电极（异羟肟酸和脂肪酸）和上清液条件下，其ζ电势都向负方向移动。带有收集器和上清液的IEP为<3.5。由于在存在试剂和上清液的情况下进行ζ电势测量是确定浮选试剂效率的最严格方法，此处获得的方铁矿zeta电位与先前在bastnäsite上的工作之间的协议表明，可以使用与bastnäsite相似的试剂方案处理方石。这对于将来由更复杂的REE矿物学组成的REE矿床的处理很重要。