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Processing Technology for Extraction of Scandium(III) from Secondary Sources – A Comprehensive Approach
Published in Abhilash, Ata Akcil, Critical and Rare Earth Elements, 2019
Pankaj Kumar Parhi, Saroj Sekhar Behera, Debadutta Das, Pramila Kumari Misra
Common methods adopted in the separation and purification of scandium from leach solution include solvent extraction, ion exchange, resin separation, liquid membrane process, adsorption, and precipitation [Borra et al., 2015, Das et al., 2018, Baba et al., 2014, Sun et al., 2011, Zhu et al., 2017, Kuroda et al., 1966 & Zhou et al., 2018b]. The studies relating to adsorption are limited, moreover, the process is very slow and nonselective. Therefore, an alternate approach is ion-exchange which is preferred in downstream operation. In ion exchange, polymeric functionalized resins are employed for the selective separation of scandium similar to other rare earth metal separation studies. Consequently, time solvent impregnated resin (SIR) process becomes more causative than the conventional ion-exchange approach. Similar to SIR, different organic commercial as well as ILs are impregnated over the resin, and thereby overall extraction efficiency and selectivity is significantly improved. SIR has been shown to be a simple and effective tool to selectively separate RE ions from aqueous solutions [Alexandratos, 2007, Zhu, 2011]. The Amberlite series resins are potentially applied as a suitable support for organic extractants (as SIR) for effective removal of rare earth metals from numerous sources. However, some SIRs have relatively very low stability during operation and the organic supports gets washed out [Zhu, 2011]. Therefore, to overcome such difficulty in the separation of scandium, the solvent extraction and SLM process is extensively applied, which is well described in the following section.
Adsorption and Ion-Exchange Processes
Published in Thomas E. Carleson, Nathan A. Chipman, Chien M. Wai, Separation Techniques in Nuclear Waste Management, 2017
The area of extraction chromatography, although not as popular as ion-exchange chromatography, has been used at various times by a variety of researchers. There are examples of its use sprinkled throughout the literature. Extraction chromatography appears to have become much more popular in the last decade, perhaps due to the lack of commercial chelating resins available for removal of specific metal ions. These extraction chromatographic materials are sometimes called solvent-impregnated resins. The work in this field was reviewed in 1973.49 The concept or need for ion-specific resins has not led to the development of ion-exchange resins that are specific for only one or two particular species. In fact, this may be almost impossible due to the similar chemistry exhibited by the various metal ions within a periodic family. The rationale behind the solvent-impregnated resins is that a specific extractant can be loaded onto a substrate; either a polymeric resin, or silica gel, or some other inert substrate. This solvent-impregnated resin now can be used to extract the specific metal ions without extracting many of the other ions that may be present in solution. There are many examples of their use in the literature over the past two decades.50–61
Phytic acid modified N1923 solvent impregnated resins for adsorption of in(III)
Published in Journal of Dispersion Science and Technology, 2022
Xuezhen Gao, Yuanyuan Wan, Junshen Liu, Xunyong Liu, Lei Guo, Shengxiao Zhang
Solvent impregnated resins (SIRs) as a kind of adsorption resins combine the advantages of resins and extractants, which load the extractant in the porous network of the resin through physical adsorption.[19] So, SIRs can be as alternative adsorbents used to extract indium. In recent years, there have been some reports on SIRs extraction of indium.[10,20–22] Although there are several articles about SIRs absorption of indium, most of which are prepared by choosing conventional extractants. However, the SIRs with a novel extractant or modified extractant used in indium adsorption have rarely been reported.
Synthesis of Adsorbents with Anion Exchange and Chelating Properties for Separation and Recovery of Precious Metals – A Review
Published in Solvent Extraction and Ion Exchange, 2020
Solvent-impregnated resins (SIRs) have attracted much attention in recent years due to their ability to selectively extract different metals. These materials feature synthetic routes much less complicated than in the case of many ion exchange and chelating resins. Basically, the synthesis of SIRs allows the utilization of liquid-liquid extractants in the manner of solid-liquid ones. Such an approach allows combining the advantages of a target-selective extractant or ionic liquid with the ease-of-use of a chelating resin.[78,79]
Recovery of Platinum and Palladium from Spent Automobile Catalyst by Solvent-Impregnated Resins
Published in Solvent Extraction and Ion Exchange, 2018
Jeong-yi Moon, Syouhei Nishihama, Kazuharu Yoshizuka
Solvent impregnated resin (SIR)[13,14,15] is an alternative separation method which is environmentally friendly and relatively easy to prepare, possessing high selectivity by integrating the unique features and process advantages of solvent extraction and ion exchange. The major disadvantage of SIRs is the loss of extractant due to solubility in the aqueous phase, which can be minimized by coating with polymers and chemical crosslinking.[16]