Adsorption Materials Development for the Separation of Actinides and Specific Fission Products from High Level Waste

Abstract

The long-term radiotoxicity of high level liquid waste (HLLW) generated in spent nuclear fuel reprocessing is governed by the content of several long-lived minor actinides (MA) and some specific fission product nuclides. To efficiently separate MA (Am, Cm) and some FPs such as Cs and Sr from the HLLW, we have been studying an advanced aqueous partitioning process, which uses selective adsorption as separation method. In this work, we prepared different types of porous silica-based organic/inorganic adsorbents with fast diffusion kinetics, improved chemical stability and low pressure drop in a packed column. So they are advantageously applicable to efficient separation of the MA and specific FP elements from HLLW. Adsorption and separation behaviors of the MA and some FP elements such as Cs and Sr were studied. Small scale separation tests using simulated and genuine nuclear waste solutions were carried out and the obtained results indicate that the proposed separation method based on selective adsorption is essentially feasible.

Separation of Minor Actinides from High-Level Liquid Waste Using Novel Silica-Based Butyl-BTP Adsorbents

“…For this purpose, we have been studying an advanced separation process involving a selective adsorption technology that uses a minimal organic solvent and compact equipment [2,3,5,[8][9][10]. The schematic Toxics 2022, 10, 741 2 of 11 flowsheet of this process is shown in Figure 1 [11]. The process is constituted by two separation columns packed with CMPO (octyl(phenyl)-N,N-diisobutylcarbamoyl-methyl phosphine oxide) and R-BTP (2,6-bis-(5,6-dialkyl-1,2,4-triazine-3-yl)pyridine, R = alkyl group) adsorbents, respectively.…”

“…Figure 1. Schematic flowsheet of the MA separation process from HLLW using the adsorption method[11].…”

Preparation of a novel CeO2/SiO2 adsorbent and its adsorption behavior for fluoride ion

“…Therefore, the attempt was made to synthesize a novel adsorbent which has the large specific surface, fast diffusion kinetics, and low pressure drop in a packed adsorption column. A novel porous silica support with the high porosity of 60%, high mechanical strength, and high radiation stability has been developed by Wei et al (2014) to make silica-based adsorbents suitable for the column operation (Wu et al, 2012;Zhang et al, 2016). Thus, a novel CeO 2 /SiO 2 adsorbent was synthesized in this study.…”