Cetylpyridinium Bromide/Polyvinyl Chloride for Substantially Efficient Capture of Rare Earth Elements from Chloride Solution.

A new sorbent cetylpyridinium bromide/polyvinylchloride (CPB/PVC) was prepared and tested to extract rare earth elements (REEs) from their chloride solutions. It was identified by FTIR, TGA, SEM, EDX, and XRD. The impact of various factors such as pH, RE ion initial concentration, contacting time, and dose amount via sorption process was inspected. The optimum pH was 6.0, and the equilibrium contact time was reached at 60 min at 25 °C. The prepared adsorbent (CPB/PVC) uptake capacity was 182.6 mg/g. The adsorption of RE ions onto the CPB/PVC sorbent was found to fit the Langmuir isotherm as well as pseudo-second-order models well. In addition, the thermodynamic parameters of RE ion sorption were found to be exothermic and spontaneous. The desorption of RE ions from the loaded CPB/PVC sorbent was investigated. It was observed that the optimum desorption was achieved at 1.0 M HCl for 60 min contact time at ambient room temperature and a 1:60 solid: liquid phase ratio (S:L). As a result, the prepared CPB/PVC sorbent was recognized as a competitor sorbent for REEs.

Rare Earth Group Separation after Extraction Using Sodium Diethyldithiocarbamate/Polyvinyl Chloride from Lamprophyre Dykes Leachate.

This study presents the first application of sodium diethyldithiocarbamate/polyvinyl chloride (DdTC/PVC) as a novel adsorbent for rare earth element (REE) sorption from leach liquors. DdTC/PVC has higher adsorption properties than other sorbents, the synthesis of DdTC/PVC is more accessible than other resins, and it is considered a more affordable sorbent. The three-liquid-phase extraction technique (TLPE) was applied to separate REEs into light, middle, and heavy rare earth elements as groups. The TLPE is an excellent achievable technique in the separation of REEs. DdTC/PVC was prepared as a sorbent to sorb rare-earth ions in chloride solution. It was described by XRD, SEM, TGA, and FTIR. The factors pH, initial rare-earth ion concentration, contact time, and DdTC/PVC dose were also analyzed. The ideal pH was 5.5, and the ideal equilibration time was found to be 45 min. The rare-earth ion uptake on DdTC/PVC was 156.2 mg/g. The rare-earth ion sorption on DdTC/PVC was fitted to Langmuir and pseudo-2nd-order models. The rare-earth ions' thermodynamic adsorption was spontaneous and exothermic. In addition, rare-earth ion desorption from the loaded DdTC/PVC was scrutinized using 1 M HCl, 45 min time of contact, and a 1:60 S:L phase ratio. The obtained rare earth oxalate concentrate was utilized after dissolving it in HCl to extract and separate the RE ions into three groups-light (La, Ce, Nd, and Sm), middle (Gd, Ho, and Er), and heavy (Yb, Lu, and Y)-via three-liquid-phase extraction (TLPE). This technique is simple and suitable for extracting REEs.