Intensified demulsification and separation of thermal oxide reprocessing interfacial crud (THORP-IFC) simulants

Abstract

Reprocessing of spent nuclear fuel for the recovery of the fi ssionable materials (mainly uranium and plutonium), is performed by solvent extraction. Thermal oxide reprocessing (THORP) is the most widely used technique in which processing fl uids gradually degrade and form stable emulsions that are referred to as interfacial crud (IFC). IFC is highly viscous and stable and its deposition in the nuclear reprocessing circuit results in blockages and plant shutdown for the recovery of IFC and cleaning of the lines. IFC is also encountered in other non-nuclear extraction processes such as crude oil production from oil wells due to the presence of naturally occurring surface active species in crude oil. In this study, we fi rst investigated the synthesis of a non-radioactive IFC simulants and subsequently examined its demulsifi cation behavior (separation into oil and aqueous components). It was concluded that the IFC is stabilized by surface active species, the removal of which results in the demulsifi cation and subsequent phase separation and the prevention of the IFC re-formation. Demulsifi cation was carried out using sulfonated, microporous, crossed-linked materials known as PolyHIPE Polymers (PHP). Demulsifi cation characteristic of the hydrophilic PHP is unique compared with other demulsifi ers, since the capture of surface active species is largely irreversible and hence, demulsifi ed IFC does not reform upon mixing of the oil and aqueous phases. It is therefore possible to remove surface active species from the reaction circuit continuously.

Co-Assembled Supported Catalysts: Synthesis of Nano-Structured Supported Catalysts with Hierarchic Pores through Combined Flow and Radiation Induced Co-Assembled Nano-Reactors

“…This results in "unconstrained" crystallite growth as discussed further in Section 3. 16. Figure 19 illustrates the porous structure of Ni/Si = 1/4 Mw-AB catalyst which was obtained from the microwave irradiation of catalyst/support precursor fluid at 1 kW followed by heat treatment at 600 °C (Method-C, Section 3.8).…”

Preparation of Nanostructured Microporous Metal Foams through Flow Induced Electroless Deposition

“…PolyHIPE Polymers can be chemically and biologically functionalized [16][17][18][19][20] in order to achieve mimicking of nature's processing strategy and applied to tissue engineering, bioprocess intensification, and agroprocess intensification. Furthermore, nonbiological functionalization processes were used for specific applications such as separation processes [21], fast response ion-exchange resins [22], and environmental and energy conversion processes [23].…”

Surface modification of monolithic PolyHIPE Polymers for anionic functionality and their ion exchange behavior

“…Due to these attributes, PHPs and their metallic, ceramic or composite forms have been used in the emerging technology of Process Intensification (PI), which facilitates the establishment of green processes. In addition to use of PHPs in analytical sciences, the important specific applications of PHPs in PI include: Agro‐PI, Bio‐PI, Chemical‐PI, including Separation processes, Energy and Environmental‐PI, and medicine and tissue engineering . A recent review of some of these applications is available…”

“…In most of the large scale applications of PHPs, such as agriculture and separation and energy‐environmental processes, the bulk and surface functionality of PHP requires ion‐exchange capacity. The required anionic or cationic characteristics are dictated by the nature of the application.…”

“…The most important difference between the commercial and PHP‐based ion‐exchangers is the accessibility of the ion‐exchange sites in PHP which accelerates the exchange kinetics and allows the utilization of full exchange capacity.…”